[26]

 

ADHESIVES

 

Amber Cements.

 

I.    To solder together two pieces of yellow amber, slightly heat the parts to be united and moisten them with a solution of caustic soda; then bring the two pieces together quickly.

 

II.   Dissolve in a closed bottle 75 parts of cut-up caoutchouc in 60 parts of chloroform. Add 15 parts of mastic and let the mixture stand in the cold until all has dissolved.

 

III.  Moisten the pieces to be joined with caustic potash and press them together when warm. The union is so perfect that no trace of the juncture is visible. A concentrated alcoholic solution of the rosin over the amber, soluble in alcohol, is also employed for this purpose. Another medium is a solution of hard and very finely powdered copal in pure sulphuric ether. Coat both fractures, previously well cleaned, with this solution and endeavor to combine them intimately by tying or pressing.

 

IV.   In 30 parts by weight of copal dissolve 30 parts by weight of alumina by means of a water bath. Bathe the surface to be cemented with this gelatinous liquid, but very slightly. Unite the fractures and press them together firmly until the mixture is dry.

 

Acid-Proof Cements for Stoneware and Glass.

 

I.    Mix with the aid of heat equal weights of pitch, rosin, and plaster of Paris.

 

II.   Mix silicate of soda to a paste with ground glass.

 

III.  Mix boiled oil to a paste with china clay.

 

IV.   Mix coal tar to a paste with pipe clay.

 

V.    Mix boiled oil to a paste with quicklime.

 

VI.   Mix with the aid of heat: Sulphur, 100 pounds; tallow, 2 pounds; rosin, 2 pounds. Thicken with ground glass.

 

VII.  Mix with the aid of heat: Rosin, 2 pounds; sulphur, 2 pounds; brickdust, 4 pounds.

 

VIII. Mix with the aid of heat 2 pounds of india rubber and 4 pounds of boiled oil. Thicken with 12 pounds of pipe clay.

 

IX.   Fuse 100 pounds of india rubber with 7 pounds of tallow. Then make to a paste with dry slaked lime and finally add 20 pounds of red lead.

 

X.    Mix with the aid of heat: Rosin, 24 pounds; red ocher, 8 pounds; boiled oil, 2 pounds; plaster of Paris, 4 pounds.

 

 

 

Acid-Proof Cement for Wood, Metals, etc.

 

I.   

Powdered asbestos                   2 parts

Ground baryta                       1 part

Sodium water-glass solution         2 parts

 

Mix. 

 

II.   To withstand hot nitric acid the following is used:

 

Sodium water-glass solution         2 parts

Sand                                1 part

Asbestos                            1 part

 

Mix. 

 

III. 

 

Asbestos                            2 parts

Sulphate of barium                  3 parts

Silicate of sodium                  2 parts

 

By mixing these ingredients a cement strong enough to resist the strongest nitric acid will be obtained.

 

IV.   If hot acids are dealt with, the following mixture will be found to possess still more resistant powers:

 

Silicate of sodium (50º Baumé)            2 parts

Fine sand                                 1 part

Asbestos                                  1 part

 

Both these cements take a few hours to set. If the cement is wanted to set at once, use silicate of potassium, instead of silicate of sodium. This mixture will be instantly effective and possesses the same power of resistance as the other.

 

Directions for Repairing Broken Glass, Porcelain, Bric-a-Brac.

 

Broken glass, china, bric-a-brac, and picture frames, not to name casts, equire each a different cement in fact, several different cements. Glass may be beautifully mended to look at, but seldom so as to be safely used. For clear glass the best cement is isinglass dissolved in gin. Put 2 ounces of isinglass in a clean, wide-mouthed bottle, add half a pint of gin, and set in the sun until dissolved. Shake well every day, and before using strain through double lawn, squeezing very gently.

 

Spread a white cloth over the mending table and supply it with plenty of clean linen rags, strong rubber bands, and narrow white tape, also a basin of tepid water and a clean soft towel. Wash the broken glass very clean, especially along the break, but take care not to chip it further. Wet both broken edges well with the glue, using a camel's-hair pencil. Fit the break to a nicety, then slip on rubber bands length- and cross-wise, every way they will hold. If they will not hold true as upon a stemmed

 

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[27]

 

ADHESIVES

 

thing, a vase or jug or scent bottle, string half a dozen bands of the same size and strength upon a bit of tape, and tie the tape about neck or base before beginning the gluing. After the parts are joined slip another tape through the same bands and tie it above the fracture; thus with all their strength the bands pEull the break together. The bands can e used thus on casts of china in fact, to hold anything mendable. In glass mending the greater the pressure the better if only it stops short of the breaking point. Properly made the isinglass cement is as clear as water. When the pieces fit true one on the other the break should be hardly visible, if the pressure has been great enough to force out the tiny bubbles, which otherwise refract the light and make the line of cleavage distressingly apparent. Mended glass may be used to hold dry things as rose leaves, sachets, violet powder, even candies and fruits. But it will not bear to have any sort of liquid left standing in it, nor to be washed beyond a quick rinsing in tepid water. In wiping always use a very soft towel, and pat the vessel dry with due regard to its infirmities.

 

Mend a lamp loose in the collar with sifted plaster of Paris mixed to a very soft paste with beaten white of egg. Have everything ready before wetting up the plaster, and work quickly so it may set in place. With several lamps to mend wet enough plaster for one at a time. It takes less than 5 minutes to set, and is utterly worthless if one tries working it over. Metal work apart from the glass needs the soldering iron. Dust the break well with powdered rosin, tie the parts firmly together, lay the stick of solder above the break, and fetch the iron down on it lightly but firmly. When the solder cools, remove the melted rosin with a cloth dipped in alcohol.

 

Since breakables have so unhappy a knack of fracturing themselves in such fashion they cannot possibly stand upright, one needs a sand boX.   It is only a box of handy size with 8 inches of clean, coarse sand in the bottom. Along with it there should be some small leaden weights, with rings cast in them, running from an ounce to a quarter pound. Two of each weight are needed. In use, tapes are tied to the rings, and the pair of weights swung outside the edges of the box, so as to press in place the upper part of a broken thing to which the tapes have been fastened.

 

Set broken platters on edge in the sand box with the break up. The sand will hold them firm, and the broken bit can be slapped on. It is the same with plates and saucers. None of these commonly requires weighting. But very fine pieces where an invisible seam is wanted should be held firm until partly set, then have the pair of heaviest weights accurately balanced across the broken piece. The weights are also very useful to prop and stay topheavy articles and balance them so they shall not get out of kilter. A cup broken, as is so common with cups, can have the tape passed around it, crossing inside the handle, then be set firmly in the sand, face down, and be held by the hanging weights pulling one against the other.

 

The most dependable cement for china is pure white lead, ground in linseed oil, so thick it will barely spread smoothly with a knife. Given time enough to harden (some 3 months), it makes a seam practically indestructible. The objection to it is that it always shows in a staring white line. A better cement for fine china is white of egg and plaster. Sift the plaster three times and tie a generous pinch of it loosely in mosquito netting. Then beat the egg until it will stick to the plaster. Have the broken egg very clean, cover both with the beaten egg, dust well with the plaster, fit together at once, tie, using rubber bands if possible, wrap loosely in very soft tissue paper, and bury head and ears in the sand box, taking care that the break lies so that the sand will hold it together. Leave in the box 24 hours. After a week the superfluous plaster may be gently scraped away.

 

General Formulas for Cements for Repairing Porcelain, Glassware, Crockery, Plaster, and Meerschaum.

 

I.    An excellent cement for joining broken crockery and similar small articles can be made by melting 4 or 5 parts of rosin (or, better still, gum mastic) with 1 part of beeswax in an iron spoon or similar vessel. Apply while hot. It will not stand great heat.

 

II.   An excellent cement for porcelain and stoneware is obtained by mixing 20 parts of fish glue with an equal weight of crystallizable acetic acid and evaporate the mixture carefully to a syrupy consistency so that it forms a gelatinous mass on cooling. For use the cement thus obtained is made liquid again by heating and applied to the fracture with a brush. The pieces should now be pressed firmly together, by winding a twine tightly around them, until the cement has hardened.

 

III.  For luting vessels made of glass,

 

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[28]

 

ADHESIVES

 

porcelain, etc., which are to be used to hold strong acids, a mixture of asbestos powder, water glass, and an indifferent powder (permanent white, sand, etc.) is recommended. To begin with, asbestos powder is made into a pulp with three or four times the quantity (weight) of a solution of soda water glass (of 30º B.). The same is exceedingly fat and plastic, but is not very well suited for working, as it shrinks too much and cracks when drying. By an addition of fine writing sand of the same weight as the asbestos used, the mass can be made less fat, so as to obviate shrinking, without detracting from the plasticity. Small vessels were molded from it and dried in the air, to be tested afterwards. Put in water, the hardened mass becomes soft again and falls apart. Brought into contact, however, with very strong mineral acids, it becomes even firmer and withstands the liquid perfectly. Concentrated nitric acid was kept in such small vessels without the mass being visibly attacked or anything penetrating it. The action of the acid manifestly has the effect that silicic acid is set free from the water glass in excess, which clogs up the pores entirely and contributes to the lutation. Later on, the mass cannot be dissolved by pure water any more. The mass is also highly fire-proof. One of the molded bodies can be kept glowing in a Bunsen gas flame for about half a day after treatment with acid, without slagging in the least. For many purposes it ought to be welcome to have such a mass at hand. It cannot be kept ready for use, however, as it hardens a few hours after being prepared; if potash water glass is used, instead of the soda composition, this induration takes place still more quickly.

 

IV.   Cement for Glass, Porcelain, etc.

 

Isinglass (fish glue)               50 parts

Gum ammoniac                        4 parts

Gum mastic                          2 parts

Alcohol, 95 per cent                10 parts

Water, q. s.

 

Soak the isinglass in cold water over night, or until it has become swollen and soft throughout. In the morning throw off any superfluous fluid and throw the isinglass on a clean towel or other coarse cloth, and hang it up in such a way that any free residual water will drain away. Upon doing this thoroughly depends, in a great measure, the strength of the cement. When the gelatin has become thoroughly drained put it into a flask or other container, place it in the water bath and heat carefully until it becomes fluid, being careful not to let it come to a boil, as this injures its adhesive properties (the same may be said in regard to glues and gelatins of all kinds). Dissolve the gums in the alcohol and add the solution to the gelatin after removing the same from the water bath, and letting it cool down to about 160º F.

Stir well together or mix by agitation.

 

The following precautions must be observed: 1. Both surfaces to be joined must be absolutely clean, free from dust, dirt, grease, etc. 2. Where the cement is one that requires the application of heat before use, the objects to be united should also be heated to a point at least as high as the melting point of the cement. Otherwise, the cement on application is chilled and consequently fails to make a lasting joint. 3. The thinner the layer of cement the stronger the joint; avoid, therefore, using too much of the binding material. Cover both surfaces to be united, coapt them exactly, and press together as closely as possible. In this manner the thinnest possible layer is secured. 4. Bind the parts securely together, and let remain without loosening or attempting to use the article for 2 or 3 days or longer. A liquid cement acquires its full strength only after evaporation of the fluids used as solvents, and this can occur only from the infinitesimal line of exposed surface.

 

V.    Liquid Porcelain Cement. Fish glue, 20 parts; glass acetic acid, 20 parts; heat together until the mass gelatinizes on cooling.

 

VI.   Take 1 ounce of Russian isinglass, cut in small pieces, and bruise well; then add 6 ounces of warm water, and leave it in a warm place for from 24 to 48 hours. Evaporate the resulting solution to about 3 ounces. Next dissolve 1/2 ounce of mastic in 4 ounces of alcohol, and add the mastic solution to the isinglass in small quantities at a time, continuing the heat and stirring well. While still hot strain the liquid through muslin.

 

VII.  For optical glasses, Canada balsam is employed, the two pieces being firmly pressed together. After a while, especially by humidity, punctures will form, and the glass is separated by a mist of varying reflexes, while in certain climates the heat will melt the balsam. For all other glass articles which require only simple treatment, such as knobs of covers, plates, etc., silicate of potash is excellent.

 

VIII. Glass Cement. Dissolve in 150 parts of acetic acid of 96 per ent, 100

 

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[29]

 

ADHESIVES

 

parts of gelatin by the use of heat, and add ammonium bichromate, 5 parts. This glue must be kept away from the light.

 

IX.  

White glue                          10 parts

Potassium bichromate                2 parts

Water                               100 parts

 

The glue is dissolved in a portion of the water by the aid of heat, the bichromate in the remainder, and the liquids mixed, the mixing being done in a feebly lighted place, and the mixture is then kept in the dark. It is applied in feeble light, being reliquefied by gentle heat,

and the glass, the fractured pieces being tightly clamped together, is then exposed to a strong light for some time. By this exposure the cement becomes insoluble. This is waterproof cement for glass.

 

X.    Diamond Glass Cement. Dissolve 100 parts of fish glue in 150 parts of 90 per cent alcohol and add, with constant stirring, 200 parts of powdered rosin. This cement must be preserved in absolutely tight bottles, as it solidifies very quickly.

 

XI To unite objects of crystal dissolve 8 parts of caoutchouc and 100 parts of gum mastic in 600 parts of chloroform. Set aside, hermetically closed, for 8 days; then apply with a brush, cold.

 

XII.  To make a transparent cement for glass, digest together for a week in the cold 1 ounce of india rubber, 67 ounces of chloroform, and 40 ounces of mastic.

 

XIII. A mixture of traumaticin, a solution of caoutchouc in chloroform, and a concentrated solution of water glass make a capital cement for uniting articles of glass. Not only is the joint very strong, but it is transparent. Neither changes of temperature nor moisture affect the cement.

 

XIV.  A transparent cement for porcelain is prepared by dissolving 75 parts of india rubber, cut into small pieces, in a bottle containing 60 parts chloroform; to this add 15 parts green mastic. Let the bottle stand in the cold until the ingredients have become thoroughly dissolved.

 

XV.   Some preparations resist the action of heat and moisture a short time, but generally yield very quickly. The following cement for glass has proven most resistant to liquids and heat:

 

Silver litharge                     1,000 parts

White lead                          50 parts

Boiled linseed oil                  3 parts

Copal varnish                       1 part

 

Mix the lead and litharge thoroughly, and the oil and copal in the same manner, and preserve separately. When needed for use, mix in the proportions indicated (150 parts of the powder to 4 parts of the liquid) and knead well together. Apply to the edges of the glass, bind the broken parts together, and let stand for from 24 to 48 hours.

 

XVI.  To reunite plaster articles dissolve small pieces of celluloid in ether; in a quarter of an hour decant, and use the pasty deposit which remains for smearing the edges of the articles. It dries rapidly and is insoluble in water.

 

XVII. To Mend Wedgwood Mortars. It is easy enough to mend mortars so that they may be used for making emulsions and other light work which does not tax their strength too much. But a mended mortar will hardly be able to stand the force required for powdering hard substances. A good cement for mending mortars is the following:

 

a.

Glass flour elutriated.             10 parts

Fluorspar, powdered and elutriated 20 parts

Silicate of soda                    60 parts

 

Both glass and fluorspar must be in the finest possible condition, which is best done by shaking each in fine powder, with water allowing the coarser particles to deposit, and then to pour off the remainder, which holds the finest particles in suspension. The mixture must be made very rapidly by quick stirring, and when thoroughly mixed must be at once applied. This is said to yield an excellent cement.

 

b.

Freshly burnt plaster of Paris      5 parts

Freshly burnt lime                  1 part

White of egg,                       sufficient.

 

Reduce the first two ingredients to a very fine powder and mix them well; moisten the two surfaces to be united with a small quantity of white of egg to make them adhesive; then mix the powder very rapidly with the white of egg and apply the mixture to the broken surfaces. If they are large, two persons should do this, each applying the cement to one portion. The pieces are then firmly pressed together and left undisturbed for several days. The less cement is used the better will the articles hold together.

 

c.

If there is no objection to dark colored cement, the very best that can be used is probably marine glue. This is made thus: Ten parts of caoutchouc or india rubber are dissolved in 120 parts of benzine or petroleum naphtha, with

 

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[30]

 

ADHESIVES

 

the aid of a gentle heat. When the solution is complete, which sometimes requires from 10 to 14 days, 20 parts of asphalt are melted in an iron vessel and the caoutchouc solution is poured in very slowly in a fine stream and under continued heating, until the mass has become homogeneous and nearly all the solvent has been driven off. It is then poured out and cast into greased tin molds. It forms dark brown or black cakes, which are very hard to break. This cement requires considerable heat to melt it; and to prevent it from being burnt it is best to heat a capsule containing a piece of it first on a water bath until the cake softens and begins to be liquid. It is then carefully wiped dry and heated over a naked flame, under constant stirring, up to about 300º F. The edges of the article to be mended should, if possible, also be heated to at least 212º F., so as to permit the cement to be applied at leisure and with care. The thinner the cement is applied the better it binds.

 

Meerschaum Cements.

 

I.    If the material is genuine (natural) meerschaum a lasting joint can be made between the parts by proceeding as follows: Clean a clove or two of garlic (the fresher the better) by removing all the outside hull of skin; throw into a little mortar and mash to a paste. Rub this paste over each surface to be united and join quickly. Bring the parts as closely together as possible and fasten in this position.

Have ready some boiling fresh milk; place the article in it and continue the boiling for 30 minutes. Remove and let cool slowly. If properly done, this makes a joint that will stand any ordinary treatment, and is nearly invisible. For composition, use a cement made of quicklime, rubbed to a thick cream with egg albumen.

 

II.   Mix very fine meerschaum shavings with albumen or dissolve casein in water glass, stir finely powdered magnesia into the mass, and use the cement at once. This hardens quickly.

 

Asbestos Cement. Ground asbestos may be made into a cement which will stand a high degree of heat by simply mixing it with a solution of sodium silicate. By subsequent treatment with a solution of calcium chloride the mass may be made insoluble, silicate of calcium being formed.

 

A cement said to stand a high degree of heat and to be suitable for cementing glass, porcelain, or other vessels intended to hold corrosive acids, is this one:

 

I.   

Asbestos                            2 parts

Barium sulphate                     3 parts

Sodium silicate                     2 parts

 

By mixing these ingredients a cement strong enough to resist the strongest nitric acid will be obtained. If hot acids are dealt with, the following mixture will be found to possess still more resistant

powers:

 

II.  

Sodium silicate                     2 parts

Fine sand                           1 part

Asbestos powder                     1 part

 

Both these cements take a few hours to set. If the cement is wanted to set at once, use potassium silicate instead of sodium silicate. This mixture will be instantly effective, and possesses the same power of resistance as the other.

 

Parisian Cement. Mix 1 part of finely ground glass powder, obtained by levigation, with 3 parts of finely powdered zinc oxide rendered perfectly free from carbonic acid by calcination. Besides prepare a solution of 1 part, by weight, of borax in a very small quantity of hot water and mix this with 50 parts of a highly concentrated zinc chloride solution of 1.5 to 1.6 specific gravity. As is well known the mixture of this powder with the liquid into a soft uniform paste is ccomplished only immediately before use. The induration to a stonelike mass takes place within a few minutes, the admixture of borax retarding the solidification somewhat. The pure white color of the powder may be tinted with ocher, manganese, etc., according to the shade desired.

 

Strong Cement. Pour over well-washed and cleaned casein 12 1/2 parts of

boiled linseed oil and the same amount of castor oil. Boil. Stir actively and add a small amount of a saturated aqueous solution of alum; remove from the fire and set aside. After a while a milky looking fluid will separate and rise. This should be poured off. To the residue add 120 parts of rock candy syrup and 6 parts of dextrin.

 

A Cheap and Excellent Cement. A cheap and excellent cement, insoluble after drying in water, petroleum, oils, carbon disulphide, etc., very hard when dry and of very considerable tensile strength, is composed of casein and some tannic-acid compound, as, for instance, calcium tannate, and is prepared as follows:

 

First, a tannin solution is prepared either by dissolving a tannin salt, or by extraction from vegetable sources (as barks from certain trees, etc.), to which

 

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[31]

 

ADHESIVES

 

is added clear lime water (obtained by filtering milk of lime, or by letting the milk stand until the lime subsides) until no further precipitation occurs, and red litmus paper plunged in the fluid is turned blue. The liquid is now separated from its precipitate, either by decantation or otherwise, and the precipitate is dried. In operating with large quantities of the substance, this is done by passing a stream of atmospheric air through the same. The lime tannate obtained thus is then mixed with casein in proportions running from 1:1 up to 1:10, and the mixture, thoroughly dried, is milled into the consistency of the finest powder. This powder has now only to be mixed with water to be ready for use, the consistency of the preparation depending upon the use to which it is to be put.

 

Universal Cement. Take gum arabic, 100 parts, by weight; starch, 75 parts, by weight; white sugar, 21 parts, by weight; camphor, 4 parts, by weight. Dissolve the gum arabic in a little water; also dissolve the starch in a little water. Mix and add the sugar and camphor. Boil on the water bath until a paste is formed which, on coating, will thicken.

 

Cement for Ivory. Melt together equal parts of gutta percha and ordinary Eitch. The pieces to be united have to be warmed.

 

Cement for Belts. Mix 50 parts, by weight, of fish glue with equal parts of whey and acetic acid. Then add 50 parts, by weight, of garlic in paste form and boil the whole on the water bath. At the same time make a solution of 100 parts, by weight, of gelatin in the same quantity of whey, and mix both liquids. To the whole add, finally, 50 parts, by weight, of 90-per-cent alcohol and, after filtration, a cement is obtained which can be readily applied with a brush and possesses extraordinary binding qualities.

 

Cement for Chemical Apparatus. Melt together 20 parts of gutta percha, 10 parts of yellow wax, and 30 parts of shellac.

 

Size Over Portland Cement. The best size to use on Portland cement molding for wall paper would ordinarily be glue and alum size put on thin and warm, made in proportion of 1/2 pound of glue and same weight of alum dissolved in separate pails, then poured together.

 

Aquarium Cements.

 

I.   

Litharge                            3 ounces

Fine white sand                     3 ounces

Plaster of Paris                    3 ounces

Rosin, in fine powder               1 ounce

Linseed oil                         enough.

Drier                               enough.

 

Mix the first three ingredients, add sufficient linseed oil to make a homogeneous paste, and then add a small quantity of drier. This should stand a few hours before it is used. It is said that glass joined to iron with this cement will break before it will come loose.

 

II.  

Litharge 1 ounce

Fine white sand                     1 ounce

Plaster of Paris                    1 ounce

Manganese borate                    20 grains

Rosin, in fine powder               3 pounds

Linseed varnish oil                 enough.

 

III.  Take equal parts of flowers of sulphur, ammonium chloride, and ron filings, and mix thoroughly with boiled linseed oil. Finally, add enough white lead to form a thin paste.

 

IV.  

Powdered graphite                   6 parts

Slaked lime                         3 parts

Barium sulphate                     8 parts

Linseed varnish oil                 7 parts

 

V.    Simply mix equal parts of white and red lead with a little kettle-boiled linseed oil.

 

Substitute for Cement on Grinder Disks. A good substitute in place of glue or various kinds of cement for fastening emery cloth to the disks of grinders of the Gardner type is to heat or warm the disk and apply a thin coating of beeswax; then put the emery cloth in place and allow to set and cool under pressure.

 

Knockenplombe. If 1 part of thymol be mixed with 2 parts of idoform we obtain a substance that retains its fluidity down to 72 C. (161.6º F.). If the temperature be carried down to 60 C. (140º F.) it suddenly becomes solid and hard. If, in its liquid condition, this substance be mixed intimately with an equal quantity of calcined bone, it forms

a cement that can be molded or kneaded into any shape, that, at the temperature of the body (98º F.), becomes as hard as stone, a fact that suggests many useful purposes to which the mixture may be put.

 

Cement for General Use. Take gum arabic, 100 parts, by weight; starch, 75

 

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[32]

 

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parts by weight; white sugar, 21 parts, by weight; camphor, 4 parts, by weight. Dissolve the gum arable in a little water. On the other hand, dissolve the starch also in some water. When this is done add the sugar and the camphor and put in a water bath. Boil until a paste is formed, which must be rather thin, because it will thicken on cooling.

 

Strong Cement. Pour over well-washed and cleaned casein 12 A parts of boiled linseed oil and the same amount of castor oil, put on the fire and bring to a boil; stir actively and add a small amount of a saturated aqueous solution of alum; remove from the fire and set aside. After standing a while a milky-looking fluid will separate at the bottom and rise to the top. This should be poured off and to the residue add 120 parts of rock-candy syrup and 6 parts of dextrine.

 

Syndeticon.

 

I.    Slake 100 parts of burnt lime with 50 parts of water,  pour off the supernatant water; next, dissolve 60 parts of lump sugar in 160 parts of water, add to the solution 15 parts of the slaked lime, heat to 70 or 80 C. (158 to 176º F.), and set aside shaking frequently. Finally dissolve 50 to 60 parts of genuine Cologne glue in 250 parts of the clear solution.

 

II.   A solution of 10 parts gum arabic and 30 parts of sugar in 100 parts of soda water glass.

 

III.  A hot solution of 50 parts of Cologne glue in 60 parts of a 20 per-cent aqueous calcium chloride solution.

 

IV.   A solution of 50 parts of Cologne glue in 60 parts of acetic acid.

 

V.    Soak isinglass (fish bladder) in acetic acid of 70 per cent until it swells up, then rub it up, adding a little water during the process.

 

"Shio Liao." Under this name the Chinese manufacture an excellent cement which takes the place of glue, and with which gypsum, marble, porcelain, stone, and stoneware can be cemented. It consists of the following parts (by weight): Slaked powdered lime. 54 parts; powdered alum, 6 parts; and fresh, well-strained blood, 40 parts. These materials are stirred thoroughly until an intimately bound mass of the consistency of a more or less stiff salve is obtained. In paste form this mass is used as cement; in a liquid state it is employed for painting all sorts of articles which are to be rendered waterproof

and durable. Cardboard covers, which are coated with it two or three times, be come as hard as wood. The Chinese paint their houses with "shio liao" and glaze their barrels with it, in which they transport oil and other greasy substances.

 

LUTES.

 

Lutes always consist of a menstruum and dissolved or suspended solids, and they must not be attacked by the gases and liquids coming in contact with them. In some cases the constituents of the lute react to form a more strongly adhering mass.

 

The conditions of application are, in brief:

 

(a) Heating the composition to make it plastic until firmly fixed in place.

(b) Heating the surfaces.

(c) Applying the lute with water or a volatile solvent, which is allowed to volatilize.

(d) Moistening the surfaces with water, oil, etc. (the menstruum of the lute itself).

(e) Applying the lute in workable condition and the setting taking place by chemical reactions.

(f) Setting by hydration.

(g) Setting by oxidation.

 

These principles will be found to cover nearly all cases.

 

Joints should not be ill-fitting, depending upon the lute to do what the pipes or other parts of the apparatus should do. In most cases one part of the fitting should overlap the other, so as to make a small amount of the lute effective and to keep the parts of the apparatus rigid, as a luted joint is not supposed to be a particularly strong one, but rather one quickly applied, effective while in place and easily removed.

 

Very moderate amounts of the lute should be used, as large amounts are likely to develop cracks, be rubbed off, etc.

 

A classification may be given as follows:

 

(1) Plaster of Paris.

(2) Hydraulic cement.

(3) Clay.

(4) Lime.

(5) Asphalt and pitch.

(6) Rosin.

(7) Rubber.

(8) Linseed oil.

(9) Casein and albumen.

(10) Silicates of soda and oxy-chloride cements.

(11) Flour and starch.

(12) Miscellaneous, including core compounds.

 

I.    Plaster of Paris is, of course, often used alone as a paste, which quickly

 

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[33]

 

ADHESIVES

 

solidifies, for gas and wood distillation retorts, etc., and similar places where quickness of setting is requisite. It is more often, however, used with some fibrous material to give it greater strength.

Asbestos is the most commonly used material of these, as it will stand a high temperature. When that is not so important, straw, plush trimmings, hair, etc., are used as binders, while broken stone, glass, and various mineral substances are used as fillers, but they do not add anything to the strength. These lutes seem to be particularly suitable for oil vapors and hydrocarbon

 

Formulas:

 

(1) Plaster and water.

(2) Plaster (wet) and asbestos.

(3) Plaster (wet) and straw.

(4) Plaster (wet) and plush trimmings.

(5) Plaster (wet) and hair.

(6) Plaster (wet) and broken stone, etc.

 

II.   Hydraulic Cement. Cement is used either alone or with sand, asbestos, etc. These lutes are suitable for nitric acid. When used with substances such as rosin or sulphur, cement is probably employed because it is in such a fine state of division and used as a filler and

not because of any powers of setting by hydration.

 

Formulas:

 

(1) Cement - neat.

(2) Cement and asbestos.

(3) Cement and sand.

 

III.  Clay. This most frequently enters into the composition of lutes as a filler, but even then the very finely divided condition of certain grades renders it valuable, as it gives body to a liquid, such as linseed oil, which, unless stiffened, would be pervious to a gas, the clay in all cases being neutral. Thus, for luting pipes carrying chlorine, a stiff paste of clay and molasses has been suggested by Theo. Köller in Die Surrogate, but it soon gives way.

 

Formulas:

 

(1) Clay and linseed oil.

(2) Same, using fire clay.

(3) Clay and molasses.

 

(1) Is suitable for steam, etc.; (2) for chlorine, and (3) for oil vapors.

 

IV.   Lime is used in the old lute known as putty, which consists of caustic lime and linseed oil. Frequently the lime is replaced by chalk and china clay, but the lime should be, in part at least, caustic, so as to form a certain amount of lime soap. Lime is also used in silicate

and casein compositions, which are very strong and useful, but will be described elsewhere.

 

Formulas:

 

(1) Lime and boiled oil to stiff mass.

(2) Clay, etc., boiled oil to stiff mass.

 

V.    Asphalt and Pitch. These substances are used in lutes somewhat interchangeably. As a rule, pitch makes the stronger lutes. Tar is sometimes used, but, because of the light oils and, frequently, water contained, it is not so good as either of the others.

 

Asphalt dissolved in benzol is very useful for uniting glass for photographic, microscopical, and other uses. Also for coating wood, concrete, etc., where the melted asphalt would be too thick to cover well. Benzol is the cheapest solvent that is satisfactory for this purpose, as the only one that is cheaper would be a petroleum naphtha, which does not dissolve all the constituents of the asphalt. For waterproofing wood, brick, concrete, etc., melted asphalt alone is much used, but when a little paraffine is added, it improves its waterproofing qualities, and in particular cases boiled oil is also added to advantage.

 

Formulas:

 

1.

Refined lake asphalt.

 

2.

Asphalt                             4 parts

Paraffine                           1 part

 

3.

Asphalt                             10 parts

Paraffine                           2 parts

Boiled oil                          1 part

 

Any of these may be thinned with hot benzol or toluol. Toluol is less volatile than benzol and about as cheap, if not cheaper, the straw-colored grades being about 24 cents per gallon.

 

Examples of so-called "stone cement" are:

 

4.

Pitch                               8 parts

Rosin                               6 parts

Wax                                 1 part

Plaster                             1/4 to 1/2 part

 

5.

Pitch                               8 parts

Rosin                               7 parts

Sulphur                             2 parts

Stone powder                        1 part

 

These compositions are used to unite slate slabs and stoneware for domestic, engineering, and chemical purposes. Various rosin and pitch mixtures are used for these purposes, and the proportions of these two ingredients are determined by the consistency desired. Sulphur and stone powder are added to prevent the formation of cracks, sulphur acting chemically and stone powder mechanically

 

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[34]

 

ADHESIVES

 

Where the lute would come in contact with acid or vapors of the same, limestone should not be the powder used, otherwise it is about the best. Wax is a useful ingredient to keep the composition from getting brittle with age.

 

A class of lutes under this general grouping that are much used are so-called "marine glues" (q. V.      ). They must be tough and elastic. When used for calking on a vessel they must expand and contract with the temperature and not crack or come loose.

 

Formulas:

 

6.

Pitch                               3 parts

Shellac                             2 parts

Pure crude rubber                   1 part

 

7.

Pitch                               1 part

Shellac                             1 part

Rubber substitute                   1 part

 

These are used by melting over a burner.

 

VI.   Rosin, Shellac, and Wax.      A strong cement, used as a stone cement, is:

 

1.

Rosin                               8 parts

Wax                                 1 part

Turpentine                          1 part

 

It has little or no body, and is used in thin layers.

 

For nitric and hydrochloric acid vapors:

 

2.

Rosin                               1 part

Sulphur                             1 part

Fire clay                           2 parts

 

Sulphur gives great hardness and permanency to rosin lutes, but this composition is somewhat brittle.

 

Good waterproof lutes of this class are:

 

3.

Rosin                               1 part

Wax                                 1 part

Powdered stone                      2 parts

 

4.

Shellac                             5 parts

Wax                                 1 part

Turpentine                          1 part

Chalk, etc                          8 to 10 parts

 

For a soft air-tight paste for ground-glass surfaces:

 

5.

Wax                                 1 part

Vaseline                            1 part

 

6. A strong cement, without body, for metals (other than copper or alloys of same), porcelain, and glass is made by letting 1 part of finely powdered shellac stand with 10 parts of ammonia water until solution is effected.

 

VII.  Rubber. Because of its toughness, elasticity, and resistance to alterative influences, rubber is a very useful constituent in lutes, but its price makes its use very limited.

 

Leather Cement.

 

1.

Asphalt                             1 part

Rosin                               1 part

Gutta percha                        4 parts

Carbon disulphide                   20 parts

 

To stand acid vapors:

 

2.

Rubber                              1 part

Linseed oil                         3 parts

Fire clay                           3 parts

 

3. Plain Rubber Cement. Cut the crude rubber in small pieces and then add the solvent. Carbon disulphide is the best, benzol good and much cheaper, but gasoline is probably most extensively used because of its cheapness.

 

4. To make corks and wood impervious to steam and water, soak them in a rubber solution as above; if it is desired to protect them from oil vapors, use glue composition. (See Section IX.   )

 

VIII. Linseed Oil. This is one of the most generally useful substances we have for luting purposes, if absorbed by a porous substance that is inert.

 

Formulas:

 

1. China clay of general utility for aqueous vapors.

 

Linseed oil of general utility for aqueous vapors.

 

2. Lime forming the well-known putty.

 

Linseed oil forming the well-known putty.

 

3. Red or white lead and linseed oil.

 

These mixtures become very strong when set and are best diluted with powdered glass, clay, or graphite. There are almost an endless number of lutes using metallic oxides and linseed oil. A very good one, not getting as hard as those containing lead, is:

 

4. Oxide of iron and linseed oil.

 

IX.   Casein, Albumen, and Glue. These, if properly made, become very tough and tenacious; they stand moderate heat and oil vapors, but not acid vapors.

 

1.

Finely powdered casein              12 parts

Slaked lime (fresh)                 50 parts

Fine sand                           50 parts

Water to thick mush.

 

A very strong cement which stands moderate heat is the following:

 

2.

Casein in very fine powder          1 part

Rubbed up with silicate of soda     3 parts

 

A strong lute for general purposes.

 

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[35]

 

ADHESIVES

 

which must be used promptly when made:

 

3. White of egg made into a paste with slaked lime.

 

A composition for soaking corks, wood, packing, etc., to render them impervious to oil vapors, is:

 

Gelatine or good glue               2 parts

Glycerine                           1/2 to 1 part

Water                               6 parts

Oil of wintergreen, etc., to keep from spoiling.

 

X.    Silicate of Oxy-chloride Cements.

 

For oil vapors, standing the highest heat:

 

1. A stiff paste of silicate of soda and asbestos.

 

Gaskets for superheated steam, retorts, furnaces, etc.:

 

2. Silicate of soda and powdered glass; dry the mixture and heat.

 

Not so strong, however, as the following:

 

3.

Silicate of soda                    50 parts

Asbestos                            15 parts

Slaked lime                         10 parts

 

Metal Cement:

 

4.

Silicate of soda                    1 part

Oxides of metal, such

  as zinc oxide;

  litharge, iron oxide,

  singly or mixed                   1 part

 

Very hard and extra strong compositions:

 

5.

Zinc oxide                          2 parts

Zinc chloride                       1 part

Water to make a paste.

 

6.

Magnesium oxide                     2 parts

Magnesium chloride                  1 part

Water                               to make a paste.

 

XI.   Flour and Starch Compositions.

 

1. The well-known flaxseed poultice sets very tough, but does not stand water or condensed steam.

 

2. Flour and molasses, made by making a stiff composition of the two.

This is an excellent lute to have at hand at all times for emergency use, etc.

 

3. Stiff paste of flour and strong zinc chloride solution forms a more impervious lute, and is more permanent as a cement. This is good for most purposes, at ordinary temperature, where it would not be in contact with nitric-acid vapors or condensing steam.

 

4. A mixture of dextrine and fine sand makes a good composition, mainly used as core compound.

 

XII.  Miscellaneous.

 

1.

Litharge

Glycerine

 

Mixed to form a stiff paste, sets and becomes very hard and strong, and is very useful for inserting glass tubes, etc., in iron or brass.

For a high heat:

 

2.

Alumina                             1 part

Sand                                4 parts

Slaked lime                         1 part

Borax                               1/2 part

Water                               sufficient.

 

A class of mixtures that can be classified only according to their intended use are core compounds.

 

I.   

Dextrine                            about 1 part

Sand                                about 10 parts

With enough water                   to form a paste.

 

II.   Powdered anthracite coal, with molasses to form a stiff paste.

 

III. 

Rosin, partly saponified

  by soda lye                       1 part

Flour                               2 parts

Sand (with sufficient water)        4 parts

 

(These proportions are approximate and the amount of sand can be increased for some purposes.)

 

IV.  

Glue, powdered                      1 part

Flour                               4 parts

Sand (with sufficient water)        6 parts

 

For some purposes the following mixture is used. It does not seem to be a gasket or a core compound:

 

V.   

Oats (or wheat) ground              25 parts

Glue, powdered                      6 parts

Sal ammoniac                        1 part

 

Paper read by Samuel S. Sadtler before the Franklin Institute.

 

PASTES:

 

Dextrine Pastes.

 

I.   

Borax, powdered                     60 parts

Dextrine, light yellow              480 parts

Glucose                             50 parts

Water                               420 parts

 

By the aid of heat, dissolve the borax in the water and add the dextrine and glucose. Continue the heat, but do not let the mixture boil, and stir constantly until a homogeneous solution is obtained, from time to time renewing the water lost by evaporation with hot water. Finally, bring up to full weight (1,000 parts) by the addition of hot water, then strain through flannel. Prepared in this manner the paste remains bright and clear for a long time. It has extraordinary adhesive properties and dries very rapidly. If care is not taken to keep the cooking temperature below the boiling point of water, the paste is apt to become brown and to be very brittle on drying.

 

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[36]

 

ADHESIVES

 

II.   Dissolve in hot water a sufficient quantity of dextrine to bring it to the consistency of honey. This forms a strong adhesive paste that will keep a long time unchanged, if the water is not allowed to evaporate. Sheets of paper may be prepared for extempore labels by coating one side with the paste and allowing it to dry; by slightly wetting the gummed side, the label will adhere to glass. This paste is very useful in the office or laboratory.

 

III.  Pour over 1,000 parts of dextrine 450 parts of soft water and stir the mixture for 10 minutes. After the dextrine has absorbed the water, put the mixture over the fire, or, preferably, on a water bath, and heat, with lively stirring for 5 minutes, or until it forms a light milk-like liquid, on the surface of which little bubbles begin to form and the liquid is apparently beginning to boil. Do not allow it to come to a boil. Remove from the fire and set in a bucket of cold water to cool off. When cold add to every 1,000 parts of the solution 51 parts glycerine and as much salicylic acid as will stand on the tip of a knife blade. If the solution is too thick, thin it with water that has been boiled and cooled off again. Do not add any more glycerine or the solution will never set.

 

IV.   Soften 175 parts of thick dextrine with cold water and 250 parts of boiling water added. Boil for 5 minutes and then add 30 parts of dilute acetic acid, 30 parts glycerine, and a drop or two of clove oil.

 

V.    Powder coarsely 400 parts dextrine and dissolve in 600 parts of water. Add 20 parts glycerine and 10 parts glucose and heat to 90º C. (195º F.).

 

VI.   Stir 400 parts of dextrine with water and thin the mass with 200 parts more water, 20 parts glucose, and 10 parts aluminum sulphate. Heat the whole to 90º C. (195º F.) in the water bath until the whole mass becomes clear and liquid.

 

VII.  Warm 2 parts of dextrine, 5 parts of water, 1 part of acetic acid, 1 part of alcohol together, with occasional stirring until a complete solution is attained.

 

VIII. Dissolve by the aid of heat 100 parts of builders' glue in 200 parts of water add 2 parts of bleached shellac dissolved previously in 50 parts of alcohol. Dissolve by the aid of heat 50 parts of dextrine in 50 parts of water, and mix the two solutions by stirring the second slowly into the first. Strain the mixture through a cloth into a shallow dish and let it harden. When needed cut off a piece of sufficient size and warm until it becomes liquid and if necessary or advisable thin with water.

 

IX.   Stir up 10 parts of dextrine with sufficient water to make a thick broth. Then, over a light fire, heat and add 25 parts of sodium water glass.

 

X.    Dissolve 5 parts of dextrine in water and add 1 part of alum.

 

Fastening Cork to Metal. In fastening cork to iron and brass, even when these are lacquered, a good sealing wax containing shellac will be found to serve the purpose nicely. Wax prepared with rosin is not suitable. The cork surface is painted with the melted sealing wax.     

The surface of the metal is heated with a spirit flame entirely free from soot, until the sealing wax melts when pressed upon the metallic surface. The wax is held in the flame until it burns, and it is then applied to the hot surface of the metal. The cork surface painted with sealing wax is now held in the flame, and as soon as the wax begins to melt the cork is pressed firmly on the metallic surface bearing the wax.    

 

To Paste Celluloid on Wood, Tin, or Leather. To attach celluloid to wood, tin, or leather, a mixture of 1 part of shellac, 1 part of spirit of camphor, 3 to 4 parts of alcohol and spirit of camphor (90º) is well adapted, in which 1 part of camphor is dissolved without heating in 7 parts of spirit of wine of 0.832 specific gravity, adding 2 parts of water.

 

To Paste Paper Signs on Metal or Cloth. A piece of gutta percha of the same size as the label is laid under the latter and the whole is eated. If the heating cannot be accomplished by means of a spirit lamp the label should be ironed down under a protective cloth or paper in the same manner as woolen goods are pressed. This method is also very useful for attaching paper labels to minerals.

 

Paste for Fastening Leather, Oilcloth, or Similar Stuff to Table or Desk Tops, etc. Use the same paste for leather as for oilcloth or other goods, but moisten the leather before applying the paste. Prepare the paste as follows: Mix 2 1/4 pounds of good wheat flour with 2 tablespoonfuls of pulverized gum arabic or powdered rosin and 2 tablespoonfuls of pulverized alum in a clean dish with water enough to make a uniformly thick batter; set it over a slow fire and stir continuously until the paste is uniform and free from lumps. When the mass has become so stout that the wooden spoon or stick will stand in it

 

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[37]

 

ADHESIVES

 

upright, it is taken from the fire and placed in another dish and covered so that no skin will form on top. When cold, the table or desk top, etc., is covered with a thin coat of the paste, the cloth, etc., carefully laid on and smoothed from the center toward the edges with

a rolling pin. The trimming of edges is accomplished when the paste has dried. To smooth out the leather after pasting, a woolen cloth is of the best service.

 

To Paste Paper on Smooth Iron. Over a water bath dissolve 200 parts, by weight, of gelatine in 150 parts, by weight, of water; while stirring add 50 parts, by weight, of acetic acid, 50 parts alcohol, and 50 parts, by weight, of pulverized alum. The spot upon which it is desired to attach the paper must first be rubbed with a bit of fine emery paper.

 

Paste for Affixing Cloth to Metal.

 

Starch                              20 parts

Sugar                               10 parts

Zinc chloride                       1 part

Water                               100 parts

 

Mix the ingredients and stir until a perfectly smooth liquid results entirely free from lumps, then warm gradually until the liquid thickens.

 

To Fix Paper upon Polished Metal. Dissolve 400 parts, by weight, of dextrine in 600 parts, by weight, of water; add to this 10 parts, by weight, of glucose, and heat almost to boiling.

 

Albumen Paste. Fresh egg albumen is recommended as a paste for affixing labels on bottles. It is said that labels put on with this substance, and well dried at the time, will not loosen even when bottles are put into water and left there for some time. Albumen, dry, is almost proof against mold or ferments. As to cost, it is but little if any higher than gum arabic, the white of one egg being sufficient to attach at least 100 medium-sized labels.

 

Paste for Parchment Paper. The best agent is made by dissolving casein in a saturated aqueous solution of borax.     

 

Medical Paste. As an adhesive agent for medicinal purposes Professor Reihl, of Leipsic, recommends the viscous substance contained in the white mistletoe. It is largely present in the berries and the bark of the plant; it is called viscin, and can be produced at one-tenth the price of caoutchouc. Solutions in benzine mav be used like those of caoutchouc without causing any irritation if applied mixed with medicinal remedies to the skin.

 

Paste That Will Not Mold. Mix good white flour with cold water into a thick paste. Be sure to stir out all the lumps; then add boiling water, stirring all the time until thoroughly cooked. To 6 quarts of this add 1/2 pound light brown sugar and 1/4 ounce corrosive sublimate, dissolved in a little hot water. When the paste is cool add 1 drachm oil of lavender. This paste will keep for a long time.

 

Pasting Wood and Cardboard on Metal. In a little water dissolve 50 parts of lead acetate and 5 parts of alum. In another receptacle dissolve 75 parts of gum arabic in 2,000 parts of water. Into this gum-arabic solution pour 500 parts of flour, stirring constantly, and at gradually to the boiling point. Mingle the solution first prepared with

the second solution. It should be kept in mind that, owing to the lead acetate, this preparation is poisonous.

 

Agar Agar Paste. The agar agar is broken up small, wetted with water, and exposed in an earthenware vessel to the action of ozone pumped under pressure into the vessel from the ozonizing apparatus.

About an hour of this bleaches the agar agar and makes it freely soluble in boiling water, when solutions far more concentrated than has hitherto been possible can be prepared. On cooling, the solutions assume a milky appearance, but form no lumps and are readily reliquefied by heating. If the solution is completely evaporated, as of course happens when the adhesive is allowed to dry after use, it leaves a firmly holding mass which is insoluble in cold water. Among the uses to which the preparation can be applied are the dressing of textile fabrics and paper sizing, and the production of photographic papers, as well as the ordinary uses of an adhesive.

 

Strongly Adhesive Paste. Four parts glue are soaked a few hours in 15 parts cold water, and moderately heated till the solution becomes perfectly clear, when 65 parts boiling water are added, while stirring. In another vessel 30 parts boiled starch are previously stirred together with 20 parts cold water, so that a thin, milky liquid without lumps results. The boiling glue solution is poured into this while stirring constantly, and the whole is kept boiling another 10 minutes.

 

Paste for Tissue Paper.

 

(a)

Pulverized gum arabic               2 ounces

White sugar                         4 drachms

Boiling water                       3 fluid ounces

 

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[38]

 

ADHESIVES

 

(b)

Common laundry starch         1 1/2 ounces

Cold water                    3 fluid ounces

 

Make into a batter and pour into Boiling water 32 fluidounces

 

Mix (a) with (B), and keep in a wide-mouthed bottle.

 

Waterproof and Acid proof Pastes.

 

I.   

Chromic acid                        2 1/2 parts

Stronger ammonia                    15 parts

Sulphuric acid                      1/2 part

Cuprammonium solution               30 parts

Fine white paper                    4 parts

 

II.  

Isinglass                           a sufficient quantity

Acetic acid                         1 part

Water                               7 parts

 

Dissolve sufficient isinglass in the mixture of acetic acid and water to make a thin mucilage.

 

One of the solutions is applied to the surface of one sheet of paper and the other to the other sheet, and they are then pressed together.

 

III.  A fair knotting varnish free from surplus oil is by far the best adhesive for fixing labels, especially on metal surfaces. It dries instantly, insuring a speedy job and immediate packing, if needful, without fear of derangement. It has great tenacity, and is not only absolutely damp-proof itself, but is actually repellent of moisture, to which all water pastes are subject. It costs more, but the additional expense is often infinitesimal compared with the pleasure of a satisfactory result.

 

Balkan Paste.

 

Pale glue                           4 ounces

White loaf sugar                    2 ounces

Powdered starch.                    1 ounce

White dextrine                      1/4 pound

Pure glycerine                      3 ounces

Carbolic acid                       1/4 ounce

Boiling water                       32 ounces

 

Cut up the glue and steep it in 1/2 pint boiling water; when softened melt in a saucepan; add sugar, starch, and dextrine, and lastly the glycerine, in which carbolic acid has been mixed; add remainder of water, and boil until it thickens. Pour into jars or bottles.

 

Permanent Paste.

 

I.   

Wheat flour                         1 pound

Water, cold                         1 quart

Nitric acid                         4 fluidrachms

Boric acid                          40 grains

Oil of cloves                       20 minims

 

Mix the flour, boric acid, and water, then strain the mixture; add the nitric acid, apply heat with constant stirring until the mixture thickens; when nearly cold add the oil of cloves. This paste will have a pleasant smell, will not attract flies, and can be thinned by the addition of cold water as needed.

 

II.   Dissolve 4 ounces alum in 4 quarts hot water. When cool add as much flour as will make it of the usual consistency; then stir into it 1/2 ounce powdered rosin; next add a little water in which a dozen cloves have been steeped; then boil it until thick as mush, stirring from the bottom all the time. Thin with warm water for use.

 

Preservatives for Paste. Various antiseptics are employed for the preservation of flour paste, mucilage, etc. Boric and salicylic acids, oil of cloves, oil of sassafras, and solution of formaldehyde are among those which have given best service. A durable starch paste is produced by adding some borax to the water used in making it. A paste from 10 parts (weight) starch to 100 parts (weight) water with 1 per cent borax added will keep many weeks, while without this addition it will sour after six days. In the case of a gluing material prepared from starch paste and joiners' glue, borax has also demonstrated its preserving qualities. The solution is made by mixing 10 parts (weight) starch into a paste with water and adding 10 parts (weight) glue soaked in water to the hot solution; the addition of 1/10 part (weight) of borax to the solution will cause it to keep for weeks. It is equal to the best glue, but should be warmed and stirred before use.

 

Board Sizing. A cheap sizing for rough, weather beaten boards may be made by dissolving shellac in sal soda and adding some heavy-bodied pigment. This size will stick to grease spots. Linseed oil may be added if desired. Limewater and linseed oil make a good heavy sizing, but hard to spread. They are usually used half and half, though these proportions may be varied somewhat.

 

Rice Paste. Mix the rice flour with cold water, and boil it over a gentle fire until it thickens. This paste is quite white and becomes transparent on drying. It is very adherent and of great use for many purposes.

 

Casein Paste. A solution of tannin, prepared from a bark or from commercial tannin, is precipitated with limewater, the lime being added until the solution just turns red litmus paper blue.

 

The supernatant liquid is then decanted,

 

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[39]

 

ADHESIVES

 

and the precipitate is dried without artificial heat. The resulting calcium tannate is then mixed, according to the purpose for which the adhesive is intended, with from 1 to 10 times its weight of dry casein by grinding in a mill. The adhesive compound is soluble in water, petroleum, oils, and carbon bisulphide. It is very strong, and is applied m the form of a paste with water.

 

PASTES FOR PAPERHANGERS.

 

I.    Use a cheap grade of rye or wheat flour, mix thoroughly with cold water to about the consistency of dough, or a little thinner, being careful to remove alllumps; stir in a tablespoonful of powdered alum to a quart of flour, then pour in boiling water, stirring rapidly until the flour is thoroughly cooked. Let this cool before using, and thin with cold water.

 

II.   Venetian Paste.

(a)

4 ounces white or fish glue

8 fluidounces cold water

 

(b)

2 fluidounces Venice turpentine

 

(c)

1 pound rye flour

16 fluidounces (1 pint) cold water

 

(d)

64 fluidounces (1/2 gallon) boiling water

 

Soak the 4 ounces of glue in the cold water for 4 hours; dissolve on a water bath (glue pot), and while hot stir in the Venice turpentine. Make up (c) into a batter free from lumps and pour into (d). Stir briskly, and finally add the glue solution. This makes a very strong paste, and it will adhere to a painted surface, owing to the Venice turpentine in its composition.

 

III.  Strong Adhesive Paste.

 

(a)

4 pounds rye flour

1/2 gallon cold water

 

(b)

1 1/2 gallons boiling water

 

(c)

2 ounces pulverized rosin

 

Make (a) into a batter free from lumps; then pour into (b). Boil if necessary, and while hot stir in the pulverized rosin a little at a time. This paste is exceedingly strong, and will stick heavy wall paper or thin leather. If the paste be too thick, thin with a little hot water; never thin paste with cold water.

 

IV.   Flour Paste.

 

(a)

2 pounds wheat flour

32 fluidounces (1 quart) cold water

 

(b)

1 ounce alum

4 fluidounces hot water

 

(c)

96 fluidounces (1/2 gallon) boiling water

 

[NOTE: One of these measurements has to be wrong in the original. It is either 64 oz. or 3/4 gal.]

 

Work the wheat flour into a batter free from lumps with the cold water. Dissolve the alum as designated in (b). Now stir in (a) and (c) and, if necessary, continue boiling until the paste thickens into a semitransparent mucilage, after which stir in solution (b). The above makes a very fine paste for wall paper.

 

V.    Elastic or Pliable Paste.

 

(a)

4 ounces common starch

2 ounces white dextrine

10 fluid ounces cold water

 

(b)

1 ounce borax

3 fluid ounces glycerine

64 fluid ounces (1/2 gallon) boiling water

 

Beat to a batter the ingredients of (a). Dissolve the borax in the boiling water; then add the glycerine, after which pour (a) into solution (b) . Stir until it becomes translucent. This paste will not crack, and, being very pliable, is used for paper, cloth, leather, and other material where flexibility is required.

 

VI.   A paste with which wall paper can be attached to wood or masonry, adhering to it firmly in spite of dampness, is prepared, as usual, of rye flour, to which, however, are added, after the boiling, 8 1/3 parts, by weight, of good linseed-oil varnish and 8 1/3 parts, by weight, of turpentine to every 500 parts, by weight.

 

VII.  Paste for Wall Paper. Soak 18 pounds of bolus (bole) in water, after it has been beaten into small fragments, and pour off the supernatant water. Boil 10 ounces of glue into glue water, mix it well with the softened bolus and 2 pounds plaster of Paris and strain through a sieve by means of a brush. Thin the mass with water to the consistency of a thin paste. The paste is now ready for use. It is not only much cheaper than other varieties, but has the advantage over them of adhering better to whitewashed walls, and especially such as have been repeatedly coated over the old coatings which were not thoroughly removed. For hanging fine wall paper this paste is less commendable, as it forms a white color, with which the paper might easily become soiled if great care is not exercised in applying it. If the fine wall paper is mounted on ground paper, however, it can be recommended for pasting the ground paper on the wall.

 

LABEL PASTES:

 

Pastes to Affix Labels to Tin. Labels separate from tin because the paste becomes too dry. Some moisture is presumably always present; but more is required to cause continued adhesion in the case of tin than where the container is of

 

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[40]

 

ADHESIVES

 

glass. Paste may be kept moist by the addition of calcium chloride, which is strongly hygroscopic, or of glycerine.

 

The following formulas for pastes of the type indicated were proposed by Leo Eliel:

 

I.   

Tragacanth                          1 ounce

Acacia                              4 ounces

Thymol                              14 grains

Glycerine                           4 ounces

Water                               sufficient to make 2 pints

 

Dissolve the gums in 1 pint of water, strain, and add the glycerine, in which the thymol is suspended; shake well and add sufficient water to make 2 pints. This separates on standing, but a single shake mixes it sufficiently for use.

 

II.  

Rye flour                           8 ounces

Powdered acacia.                    1 ounce

Glycerine                           2 ounces

Oil of cloves                       40 drops

 

Rub the rye flour and acacia to a smooth paste with 8 ounces of cold water; strain through cheese cloth, and pour into 1 pint of boiling water, and continue the heat until as thick as desired. When nearly cold add the glycerine and oil of cloves.

 

III. 

Rye flour                           5 parts

Venice turpentine                   1 part

Liquid glue                         a sufficient quantity

 

Rub up the flour with the turpentine and then add sufficient freshly prepared glue (glue or gelatine dissolved in water) to make a stiff paste. This paste dries slowly.

 

IV.  

Dextrine                            2 parts

Acetic acid                         1 part

Water                               5 parts

Alcohol, 95 per cent                1 part

 

Dissolve the dextrine and acetic acid in water by heating together in the water bath, and to the solution add the alcohol.

 

V.   

Dextrine                            3 pounds

Borax                               2 ounces

Glucose                             5 drachms

Water                               3 pints 2 ounces

 

Dissolve the borax in the water by warming, then add the dextrine and glucose, and continue to heat gently until dissolved.

 

Another variety is made by dissolving a cheap Ghatti gum in limewater, but it keeps badly.

 

VI.   Add tartaric acid to thick flour paste. The paste is to be boiled until quite thick, and the acid, previously dissolved in a little water, is added, the proportion being about 2 ounces to the pint of paste.

 

VII.  Gum arabic, 50 parts; glycerine, 10 parts; water, 30 parts; liq. Stibii chlorat., 2 parts.

 

VIII. Boil rye flour and strong glue water into a mass to which are added, for 1,000 parts, good linseed-oil varnish 30 parts and oil of turpentine 30 parts. This mixture furnishes a gluing agent which, it is claimed, even renders the labels proof against being loosened by moisture.

 

IX.   Pour 140 parts of distilled cold water over 100 parts of gum arabic in a wide-necked bottle and dissolve by frequent shaking. To the solution, which is ready after standing for about 3 days, add 10 parts of glycerine; later, 20 parts of diluted acetic acid, and finally 6 parts of aluminum sulphate, then straining it through a fine-hair sieve.

 

X.    Good glue is said to be obtained by dissolving 1 part of powdered sugar in 4 parts of soda water glass.

 

XI.   A glue for bottle labels is prepared by dissolving borax in water; soak glue in this solution and dissolve the glue by boiling. Carefully drop as much acetic acid into the solution as will allow it to remain thin on cooling. Labels affixed with this agent adhere firmly and do not become moldy in damp cellars.

 

XII.  Dissolve some isinglass in acetic acid and brush the labels over with it. There will be no cause to complain of their coming off, nor of striking through the paper. Take a wide-mouthed bottle, fill about two-thirds with commercial acetic acid, and put in as much isinglass as the liquid will hold, and set aside in a warm place until completely dissolved. When cold it should form a jelly. To use it place the bottle in hot water. The cork should be well-fitting and smeared with vaseline or melted paraffine.

 

How to Paste Labels on Tin. Brush over the entire back of the label with a flour paste, fold the label loosely by sticking both ends together without creasing the center, and throw to one side until this process has been gone through with the whole lot. Then unfold each label and place it on the can in the regular manner. The paste ought not to be thicker than maple syrup. When of this consistency it soaks through the label and makes it pliable and in a condition to be easily rubbed into position. If the paste is too thick it dries quickly, and does not soak through the label sufficiently. After the labels have been placed upon the cans the latter must be

 

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[41]

 

ADHESIVES

 

kept apart until dry. In putting the paste upon the labels in the first place, follow the method of placing the dry labels over one another, back sides up, with the edge of each just protruding over the edge of the one beneath it, so that the fingers may easily grasp the label after the pasting has been done.

 

Druggists' Label Paste. This paste, when carefully made, is an admirable one for label use, and a very little will go a long way:

 

Wheat flour                         4 ounces

Nitric acid                         1 drachm

Boric acid                          10 grains

Oil of cloves                       5 drops

Carbolic acid                       1/2 drachm

 

Stir flour and water together, mixing thoroughly, and add the other ingredients. After the stuff is well mixed, heat it, watching very carefully and removing the instant it stiffens.

 

To Attach Glass Labels to Bottles. Melt together 1 part of rosin and 2 parts of yellow wax, and use while warm.

 

Photographic Mountants (see also Photography). Owing to the nature of the different papers used for printing photographs, it is a matter of extreme importance to use a mountant that shall not set up decomposition in the coating of the print. For example, a mountant that exhibits acidity or alkalinity is injurious with most varieties of paper; and in photography the following formulas for pastes, mucilages, etc., have therefore been selected with regard to their absolute immunity from setting up decomposition in the print or changing its tone in any way. One of the usual mountants is rice starch or else rice water. The latter is boiled to a thick jelly, strained, and the strained mass used as an agglutinant for attaching photographic prints to the mounts. There is nothing of an injurious nature whatever in this mountant, neither is there in a mucilage made with gum dragon.

 

This gum (also called gum tragacanth) is usually in the form of curls

(i.e, leaf gum), which take a long time to properly dissolve in water - several weeks, in fact - but during the past few years there has been put on the market a powdered gum dragon which does not occupy so many days in dissolving. To make a mucilage from gum dragon a very large volume of water is required. For example, 1 ounce of the gum, either leaf or powder, will swell up and convert 1 gallon of water into a thickish mucilage in the course of 2 or 3 weeks. Only cold water must be used, and before using the mucilage, all whitish lumps (which are particles of undissolved gum) should be picked out or else the mucilage strained. The time of solution can be considerably shortened (to a few hours) by acidifying the water in which the gum is placed with a little sulphuric or oxalic acid; but as the resultant mucilage would contain traces of their presence, such acids are not permissible when the gum-dragon mucilage is to be used for mounting photographs.

 

Glycerine and gum arabic make a very good adhesive of a fluid nature suited to mounting photographs; and although glycerine is hygroscopic by itself, such tendency to absorb moisture is checked by the reverse nature of the gum arabic; consequently an deal fluid mucilage is produced. The proportions of the several ingredients are these:

 

Gum arabic, genuine (gum acacia,

  not Bassora gum)                  4 ounces

Boiling water                       12 ounces

Glycerine, pure                     1 ounce

 

First dissolve the gum in the water, and then stir in the glycerine, and allow all debris from the gum to deposit before using. The following adhesive compound is also one that is free from chemical reactions, and is suited for photographic purposes:

 

Water                               2 pints

Gum dragon, powdered                1 ounce

Gum arabic, genuine                 4 ounces

Glycerine                           4 ounces

 

Mix the gum arabic with half the water, and in the remainder of the water dissolve the gum dragon. When both solids are dissolved, mix them together, and then stir in the glycerine.

 

The following paste will be found a useful mountant:

 

Gum arabic, genuine                 1 ounce

Rice starch                         1 ounce

White sugar                         4 ounces

Water, q. s.

 

Dissolve the gum in just sufficient water to completely dissolve it, then add the sugar, and when that has completely dissolved stir in the starch paste, and then boil the mixture until the starch is properly cooked.

 

A very strong, stiff paste for fastening cardboard mounts to frames, wood, and other materials is prepared by making a bowl of starch paste in the usual way, and then adding 1 ounce of Venice turpentine per pound of paste, and boil-

 

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[42]

 

ADHESIVES

 

ing and stirring the mixture until the thick turpentine has become well incorporated. Venice turpentine stirred into flour paste and boiled will also be found a very adhesive cement for fastening cardboard, strawboard, leatherette, and skiver leather to wood or metal; but owing to the resinous nature of the Venice turpentine, such pastes are not suitable for mounting photographic prints. The following half-dozen compounds are suitable mountants to use with silver prints:

 

Alcohol, absolute                   10 ounces

Gelatine, good                      1 ounce

Glycerine                           1/2 to 1 ounce

 

Soak the gelatine in water for an hour or two until it is completely softened; take the gelatine out of the water, and allow it to drain, and put it into a bottle and pour alcohol over it; add the glycerine (if the gelatine is soft, use only 1/2 ounce; if the gelatine is hard, use 1 ounce of the glycerine), then melt the gelatine by standing the bottle in a vessel of hot water, and shake up very well. For use, remelt by heat. The alcohol prevents the prints from stretching or cockling, as they are apt to, under the influence of the gelatine.

 

In the following compound, however, only sufficient alcohol is used to serve as an antiseptic, and prevent the agglutinant from decomposing: Dissolve 4 ounces of photographic gelatine in 16 ounces of water (first soaking the gelatine therein for an hour or two until it is completely softened), then remove the gelatine from the water, allow it to drain, and put it into the bottle, and pour the alcohol over it, and put in the glycerine (if the gelatine is soft, use only 1/2 ounce; if the gelatine is hard, use 1 ounce of the glycerine), then melt the gelatine by standing the bottle in a vessel of hot water, and shake up well and mix thoroughly. For use, remelt by heat. The alcohol prevents the print from stretching or cockling up under the influence of the gelatine.

 

The following paste agglutinant is one that is very permanent and useful for all purposes required in a photographic studio: Take 5 pints of water, 10 ounces of arrowroot, 1 ounce of gelatine, and a 1/2 pint (10 fluidounces) of alcohol, and proceed to combine them as follows:

Make arrowroot into a thick cream with a little of the water, and in the remainder of the water soak the gelatine for a few hours, after which melt the gelatine in the water by heating it, add the arrowroot paste, and bring the mixture to the boil and allow to boil for 4 or 5 minutes, then allow to cool, and mix in the alcohol, adding a few drops of oil of cloves.

 

Perhaps one or the most useful compounds for photographic purposes is that prepared as follows: Soak 4 ounces of hard gelatine in 15 ounces of water for a few hours, then melt the gelatine by heating it in a glue pot until the solution is quite clear and free from lumps, stir

in 65 fluidounces of cold water so that it is free from lumps, and pour in the boiling-hot solution of gelatine and continue stirring, and if the starch is not completely cooked, boil up the mixture for a few minutes until it "blows," being careful to keep it well stirred so as not to burn; when cold add a few drops of carbolic acid or some essential oil as an antiseptic to prevent the compound from decomposing or becoming sour.

 

A useful photographic mucilage, which is very liquid, is obtained by mixing equal bulks of gum-arabic and gum-dragon mucilages of the same consistence. The mixture of these mucilages will be considerably thinner than either of them when alone.

 

As an agglutinant for general use in the studio, the following is recommended: Dissolve 2 ounces of gum arabic in 5 ounces of water, and for every 250 parts of the mucilage add 20 parts of a solution of sulphate of aluminum, prepared by dissolving 1 part of the sulphate in

20 parts of water (common alum should not be used, only the pure aluminum sulphate, because common alum is a mixture of sulphates, and usually contaminated with iron salts). The addition of the sulphate solution to the gum mucilage renders the latter less hygroscopic, and practically waterproof, besides being very adhesive to any materials, particularly those exhibiting a smooth surface.

 

MUCILAGES:

 

For Affixing Labels to Glass and Other Objects.

 

I.    The mucilage is made by simply pouring over the gum enough water to a little more than cover it, and then, as the gum swells, adding more water from time to time in small portions, until the mucilage is brought to such consistency that it may be easily spread with the brush. The mucilage keeps fairly well without the addition of any antiseptic.

 

II.  

Tragacanth                          1 ounce

Acacia                              4 ounces

Thymol                              14 grains

Glycerine                           4 ounces

Water,                              sufficient to make 2 pints

 

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[43]

 

ADHESIVES

 

Dissolve the gums in 1 pint of water, strain and add the glycerine, in which the thymol is suspended; shake well and add sufficient water to make 2 pints. This separates on standing, but a single shake mixes it sufficiently for use.

 

III. 

Rye flour                           8 ounces

Powdered acacia                     1 ounce

Glycerine                           2 ounces

Oil of cloves                       40 drops

Water,                              a sufficient quantity.

 

Rub the rye flour and the acacia to a smooth paste with 8 ounces of cold water; strain through cheese cloth, and pour into 1 pint of boiling water and continue the heat until as thick as desired. When nearly cold add the glycerine and oil of cloves.

 

IV.   One part, by weight, of tragacanth, when mixed with 95-per-cent alcohol to form 4 fluidounces, forms a liquid in which a portion of the tragacanth is dissolved and the remainder suspended; this remains permanently fluid, never deteriorates, and can be used in place of

the present mucilage; 4 to 8 minims to each ounce of mixture is sufficient to suspend any of the insoluble substances usually given in mixtures.

 

V.    To 250 parts of gum-arabic mucilage add 20 parts of water and 2 parts of sulphate of alumina and heat until dissolved.

 

VI.   Dissolve 1/2 pound gum tragacanth, powdered, 1/4 pound gum arabic, powdered, cold water to the desired consistency, and add 40 drops carbolic acid.

 

Mucilage of Acacia. Put the gum, which should be of the best kind, in a flask the size of which should be large enough to contain the mucilage with about one fifth of its space to spare (i.e, the product should fill it about four -fifths full). Now tare, and wash the gum with distilled water, letting the latter drain away as much as possible before proceeding further. Add the requisite quantity of distilled water slowly, which, however, should first have added to it about 10 per cent of limewater. Now cork the flask, and lay it, without shaking, horizontally in a cool place and let it remain quietly for about 3 hours, then give it a half turn to the right without disturbing its horizontal position. Repeat this operation three or four times during the day, and keep it up until the gum is completely dissolved (which will not be until the fourth day probably), then strain through a thin cloth previously wet with distilled water, avoiding, in so doing, the formation of foam or bubbles. This precaution should also be observed in decantation of the percolate into smaller bottles provided with paraffine corks. The small amount of lime water, as will be understood, is added to the solvent water in order to prevent the action of free acid.

 

Commercial Mucilage. Dissolve 1/2 pound white glue in equal parts water and strong vinegar, and add 1/4 as much alcohol and 1/2 ounce alum dissolved in a little water. To proceed, first get good glue and soak in cold water until it swells and softens. Use pale vinegar. Pour off the cold water, then melt the glue to a thick paste in hot water, and add the vinegar hot. When a little cool add the alcohol and alum water.

 

To Render Gum Arabic More Adhesive.

 

I.    Add crystallized aluminum sulphate in the proportion of 2 dissolved in 20 parts of water to 250 parts of concentrated gum solution (75 parts of gum in 175 parts of water).

 

II.   Add to 250 parts of concentrated gum solution (2 parts of gum in 5 parts of water) 2 parts of crystallized aluminum sulphate dissolved in 20 parts of water. This mixture glues even unsized paper, pasteboard on pasteboard, wood on wood, glass, porcelain, and other substances on which labels frequently do not adhere well.

 

Envelope Gum. The gum used by the United States Government on postage stamps is probably one of the best that could be used not only for envelopes but for labels as well. It will stick to almost any surface. Its composition is said to be the following:

 

Gum arabic                          1 part

Starch                              1 part

Sugar                               4 parts

Water,                              sufficient to give the desired   consistency.

 

The gum arabic is first dissolved in some water, the sugar added, then the starch, after which the mixture is boiled for a few minutes in order to dissolve the starch, after which it is thinned down to the desired consistency.

 

Cheaper envelope gums can be made by substituting dextrine for the gum

arabic, glucose for the sugar, and adding boric acid to preserve and help stiffen it.

 

Mucilage to Make Wood and Pasteboard Adhere to Metals. Dissolve 50 parts, by weight, of lead acetate together with 5 parts, by weight, of alum in a little water. Make a separate solution of 75 parts, by weight, of gum arabic in 2,000 parts, by weight, of water, stir in this 500

 

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[44]

 

ADHESIVES

 

parts, by weight, of flour, and heat slowly to boiling, stirring the while. Let it cool somewhat, and mix with it the solution containing the lead acetate and alum, stirring them well together.

 

Preservation of Gum Solution. Put a small piece of camphor in the mucilage bottle. Camphor vapors are generated which kill all the bacterial germs that have entered the bottle. The gum maintains its adhesiveness to the last drop.

 

ADULTERANTS IN FOODS:

See Foods.

 

ADUROL DEVELOPER:

See Photography.

 

AESCO QUININE:

See Horse Chestnut.

 

AGAR AGAR PASTE:

See Adhesives.

 

AGATE, BUTTONS OF ARTIFICIAL.

 

Prepare a mixture or frit of 33 parts of quartz sand, 65 parts calcium phosphate, and 2 parts of potash. The frit, which has been reduced by heat to the fusing point, is finely ground, intimately mingled with a small quantity of kaolin and pressed in molds which yield button-shaped masses. These masses, after having been fired, are given a transparent glaze by any of the well-known processes.

 

AGATE (IMITATION):

See Gems, Artificial.

 

AGING OF SILK:

See Silk.

 

AGING, SILVER AND GOLD:

See Plating.

 

AIR BATH.

 

This air bath is employed in cases in which, upon drying or heating substances, acid vapors arise because the walls of the bath are not attacked by them. For the production of the drying apparatus take a flask with the bottom burst off or a bell jar tubulated above.

This is placed either upon a sand bath or upon asbestos paper, previously laid upon a piece of sheet iron. The sand bath or the sheet iron is put on a tripod, so that it can be heated by means of a burner placed underneath. The substance to be dried is placed in a glass or porcelain dish, which is put under the bell jar, and if desired the drying dish may be hung on the tripod. For regulating the temperature the tubulure of the jar is closed with a pierced cork, through whose aperture the thermometer is thrust. In order to permit the vapors to escape, the cork is grooved lengthwise along the periphery.

 

AIR BUBBLES IN GELATINE:

See Gelatine.

 

AIR, EXCLUSION OF, FROM SOLUTIONS:

See Photography.

 

AIR-PURIFYING.

 

Ozonatine is a fragrant air-purifying preparation consisting of dextrogyrate turpentine oil scented with slight quantities of fragrant oils.

 

ALABASTER CLEANING:

See Cleaning Preparations and Methods.

 

ALBATA METAL:

See Alloys.

 

ALBUMEN IN URINE, DETECTION OF.

 

Patein (Pharm. Zeit.) recommends the following test for albumen in urine: Dissolve 250 grams of citric acid in a sufficient quantity of water, add enough ammonia to neutralize, then 50 grams of alcohol, and finally enough water to make 1 liter. To the acid (or acidulated) urine, one-tenth its volume of the ammonium-citrate solution made as above is added, and the whole heated in the usual manner. The appearance of the faintest turbidity is said to indicate with positive certainty the presence of albumen.

 

ALBUMEN PAPER:

See Photography.

 

ALBUMEN PASTE:

See Adhesives.

 

Alcohol

 

After the manuscript of this book was ready for the press, Congress passed the bill which has since become a law, whereby the prohibitive tax on industrial or denatured alcohol is removed. So important is this legislative measure that the Editor has deemed it wise to insert an article on the sources of alcohol and the manufacture of alcohol from farm products. Because the first portion of the book was in type when this step was decided upon, the Editor was compelled to relegate to a later page a monograph which should properly have appeared here. The reader will find the matter on alcohol referred to under the heading

 

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ALCOHOL

 

[45]

 

"Spirit"; likewise methods of denaturing and a list of denaturants.

 

ALCOHOL, DILUTION OF:

See Tables.

 

Alcohol, Tests for Absolute. The committee for the compilation of the

German Arzneibuch established the following tests for the determination of absolute alcohol:

 

Absolute alcohol is a clear, colorless, volatile, readily imflammable liquid which burns with a faintly luminous flame. Absolute alcohol has a peculiar odor, a burning taste, and does not affect litmus paper. Boiling point, 78.50. Specific gravity, 0.795 to 0.797. One hundred

parts contain 99.7 to 99.4 parts, by volume, or 99.6 to 99.0 parts, by weight, of alcohol.

 

Absolute alcohol should have no foreign smell and should mix with water without cloudiness.

 

After the admixture of 5 drops of silver-nitrate solution, 10 cubic centimeters of absolute alcohol should not become turbid or colored even on heating.

 

A mixture of 10 cubic centimeters of absolute alcohol and 0.2 cubic centimeter of potash lye evaporated down to 1 cubic centimeter should not exhibit an odor of fusel oil after supersaturation with dilute

sulphuric acid.

 

Five cubic centimeters of sulphuric acid, carefully covered, in a test tube, with a stratum of 5 cubic centimeters of absolute alcohol, should not form a rose-colored zone at the surface of contact, even on standing for some time.

 

The red color of a mixture of 10 cubic centimeters of absolute alcohol and 1 cubic centimeter of potassium permanganate solution should not pass into yellow before 20 minutes.

 

Absolute alcohol should not be dyed by hydrogen sulphide water or by aqueous ammonia.

 

Five cubic centimeters of absolute alcohol should not leave behind a weighable residue after evaporation on water bath.

 

Absolute Alcohol. If gelatine be suspended in ordinary alcohol it will absorb the water, but as it is insoluble in alcohol, that substance will remain behind, and thus nearly absolute alcohol will be obtained without distillation.

 

Perfumed Denaturized Alcohol.

 

East India lemon oil                1,250 parts

Mirbane oil                         1,000 parts

Cassia oil                          50 parts

Clove oil                           75 parts

Lemon oil                           100 parts

Amyl acetate                        500 parts

Spirit (95 per cent)                7,000 parts

 

Dissolve the oils in the spirit and add the amyl acetate. The mixture serves for destroying the bad odor of denaturized spirit in distilling. Use 50 parts of the perfume per 1,000 parts of spirit.

 

Solid Alcohol.

 

I.    Heat 1,000 parts of denaturized alcohol (90 per cent) in a flask of double the capacity on the water bath to about 140º F., and then mix with 28 to 30 parts of well-dried, rasped Venetian soap and 2 parts of gum lac. After repeated shaking, complete dissolution will take place. The solution is put, while still warm, into metallic vessels, closing them up at once and allowing the mixture to cool therein. The admixture of gum lac effects a better preservation and also prevents the evaporation of the alcohol. On lighting the solid spirit the soap remains behind.

 

II.   Smaragdine is a trade name for solidified alcohol. It consists of alcohol and gun cotton, colored with malachite green. It appears in the market in the form of small cubes.

 

Alcohol in Fermented Beers. Experience has shown that 1/4 pound of sugar to 1 gallon of water yields about 2 per cent of proof spirit, or about 1 per cent of absolute alcohol. Beyond this amount it is not safe to go, if the legal limit is to be observed, yet a ginger beer brewed with 1/4 pound per gallon of sugar would be a very wishy-washy compound, and there is little doubt that a much larger quantity is generally used. The more sugar that is used up to 1 1/2 or 1 1/4 pounds per gallon the better the drink will be and the more customers will relish it; but it will be as "strong" as lager and contain perhaps 5 per cent of alcohol, which will make it anything but a "temperance" drink. Any maker who is using as much as even 1/2 pound of sugar per gallon is bound to get more spirit than the law allows. Meanwhile it is scarcely accurate to term ginger beers, etc., non-alcoholic.

 

Alcohol Deodorizer.

 

Alcohol                             160 ounces

Powdered quicklime                  300 grains

Powdered alum                       150 grains

Spirit of nitrous ether             1 1/4 drachms

 

Mix the lime and alum intimately by trituration; add the alcohol and shake well; then add the spirit of nitrous ether; set aside for 7 days and filter through animal charcoal.

 

Denaturized Alcohol. There are two general classes or degrees of denaturizing, viz., the "complete" and the "incomplete," according to the purpose for

 

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[46]

 

ALCOHOL

 

which the alcohol so denaturized is to be ultimately used.

 

I.    Complete denaturization by the German system is accomplished by the

addition to every 100 liters (equal to 26 1/2 gallons of spirits:

 

(a) Two and one-half liters of the "standard” denaturizer, made of 4 parts of wood alcohol, 1 part of pyridine (a nitrogenous base obtained by distilling bone oil or coal tar), with the addition of 50 grams to each liter of oil of lavender or rosemary.

 

(b) One and one-fourth liters of the above "standard" and 2 liters of benzol with every 100 liters of alcohol.

 

II.   Incomplete denaturization i.e, sufficient to prevent alcohol from being drunk, but not to disqualify it from use for various special purposes, for which the wholly denaturized spirits would be unavailable is accomplished by several methods as follows, the quantity and nature of each substance given being the prescribed dose for each 100 liters

(26 1/2 gallons) of spirits:

 

(c) Five liters of wood alcohol or 1/2 liter of pyridine.

 

(d) Twenty liters of solution of shellac, containing 1 part gum to 2 parts alcohol of 90-per-cent purity. Alcohol for the manufacture of celluloid and pegamoid is denaturized.

 

(e) By the addition of 1 kilogram of camphor or 2 liters oil of turpentine or 1/2 liter benzol to each 100 liters of spirits.

Alcohol to be used in the manufacture of ethers, aldehyde, agaricin, white lead, bromo-silver gelatines, photographic papers and plates, electrode plates, collodion, salicylic acid and salts, aniline chemistry, and a great number of other purposes, is denaturized by the addition of

 

(f) Ten liters sulphuric ether, or 1 part of benzol, or 1/2 part oil of turpentine, or 0.025 part of animal oil.

 

For the manufacture of varnishes and inks alcohol is denaturized by the addition of oil of turpentine or animal oil, and for the production of soda soaps by the addition of 1 kilogram of castor oil. Alcohol for the production of lanolin is prepared by adding 5 liters of benzine to each hectoliter of spirits.

 

ALE.

 

The ale of the modern brewer is manufactured in several varieties, which are determined by the wants of the consumer and the particular market for which it is intended. Thus, the finer kinds of Burton, East India, Bavarian, and other like ales, having undergone a thorough fermentation, contain only a small quantity of undecomposed sugar and gum, varying from 1 to 5 per cent. Some of these are highly "hopped" or "bittered," the further to promote their preservation during transit and change of temperature. Mild or sweet ales, on the contrary, are less accentuated by lengthened fermentation, and abound in saccharine

and gummy matter. They are, therefore, more nutritious, though less intoxicating, than those previously referred to.

 

In brewing the finer kinds of ales, pale malt and the best hops of the current season's growth are always employed; and when it is desired to produce a liquor possessing little color, very great attention is paid to their selection. With the same object, the boiling is conducted with more than the usual precautions, and the fermentation is carried on at a somewhat lower temperature than that commonly allowed for other varieties of beer. For ordinary ale, intended for immediate use, the malt may be all pale; but, if the liquor be brewed for keeping, and in warm weather, when a slight color is not objectionable, one-fifth, or even one-fourth of amber malt may be advantageously employed. From 4 1/2 to 6 pounds of hops is the quantity commonly used to the one-fourth of malt, for ordinary ales; and 7 pounds to 10 pounds for "keeping" ales. The proportions, however, must greatly depend on the intended quality and description of the brewing and the period that will be allowed for its maturation.

 

The stronger varieties of ale usually contain from 6 to 8 per cent of “absolute alcohol"; ordinary strong ale, 4 1/2 to 6 per cent; mild ale, 3 to 4 percent; and table ale, 1 to 1 1/2 per cent (each by volume); together with some undecomposed saccharine, gummy, and extractive matter, the bitter and narcotic principles of the hop, some acetic acid formed by the oxidation of the alcohol, and very small and variable quantities of mineral and saline matter.

 

Ordinary ale wort (preferably pale), sufficient to produce 1 barrel, is slowly boiled with about 3 handfuls of hops, and 12 to 14 pounds of crushed groats, until the whole of the soluble matter of the latter is extracted. The resulting liquor, after being run through a coarse strainer and become lukewarm, is fermented with 2 or 3 pints of yeast; and, as soon as the fermentation is at its height, is either closely bunged up for draft or is at once put into strong stoneware bottles, which are then well corked

 

White ale is said to be very nutritious, though apt to prove laxative to those un-

 

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accustomed to its use. It is drunk in a state of effervescence or lively fermentation; the glass or cup containing it being kept in constant motion, when removed from the mouth, until the whole is consumed, in order that the thicker portion may not subside to the bottom.

 

ALE, GINGER:

See Beverages.

 

ALFENIDE METAL:

See Alloys.

 

ALKALI, HOW TO DETECT:

See Soaps.

 

ALKALOIDS, ANTIDOTES TO:

See Atropine.

 

Alloys

 

No general rules can be given for alloying metals. Alloys differing greatly in fusibility are commonly made by adding the more fusible ones, either in the melted state or in small portions at a time, to the other melted or heated to the lowest possible temperature at which a perfect union will take place between them. The mixture is usually effected under a flux, or some material that will promote liquefaction and prevent volatilization and unnecessary exposure to the air. Thus, in melting lead and tin together for solder, rosin or tallow is thrown upon the surface is rubbed with sal ammoniac; and in combining some metals, powdered charcoal is used for the same purpose. Mercury or quicksilver combines with many metals in the cold, forming AMALGAMS, or easily fusible alloys (q. V. ).

 

Alloys generally possess characteristics unshared by their component metals. Thus, copper and zinc form brass, which has a different density, hardness, and color from either of its constituents.

Whether the metals tend to unite in atomic proportions or in any definite ratio is still undetermined. The evidence afforded by the natural alloys of gold and silver, and by the phenomena accompanying the cooling of several alloys from the state of fusion, goes far to prove that such is the case (Rudberg). The subject is, however, one of considerable difficulty, as metals and metallic compounds are generally soluble in each other, and unite by simple fusion and contact. That they do not combine indifferently with each other, but exercise a species of elective affinity not dissimilar to other bodies, is clearly shown by the homogeneity and superior quality of many alloys in which the constituent metals are in atomic proportion. The variation of the specific gravity and melting points of alloys from the mean of those of their component metals also affords strong evidence of a chemical change having taken place. Thus, alloys generally melt at lower temperatures than their separate metals. They also usually possess more tenacity and hardness than the mean of their constituents.

 

Matthiessen found that when weights are suspended to spirals of hard-drawn wire made of copper, gold, or platinum, they become nearly straightened when stretched by a moderate weight; but wires of equal dimensions composed of copper-tin (12 per cent of tin), silver-platinum (36 per cent of platinum), and gold-copper (84 percent of copper) scarce- ly undergo any permanent change in form when subjected to tension by the same weight.

 

The same chemist gives the following approximate results upon the tenacity of certain metals and wires hard-drawn through the same gauge (No. 23):

 

Pounds

 

Copper, breaking strain             25-30

Tin, breaking strain under          7

Lead, breaking strain under         7

Tin-lead (20% lead) about           7

Tin-copper (12% copper)             about 7

Copper-tin (12% tin)                about 80-90

Gold (12% tin)                      20-25

Gold-copper (8.4% copper)           70-75

Silver (8.4% copper)                45-50

Platinum (8.4% copper)              45-50

Silver-platinum (30% platinum)      75-80

 

On the other hand, the malleability, ductility, and power of resisting oxygen of alloys is generally diminished. The alloy formed of two brittle metals is always brittle; that of a brittle and a ductile metal, generally so; and even two ductile metals sometimes unite to form a brittle compound. The alloys formed of metals having different fusing points are usually malleable while cold and brittle while hot. The action of the air on alloys is generally less than on their simple metals, unless the former are heated. A mixture of 1 part of tin and

3 parts of lead is scarcely acted on at common temperatures; but at a red heat it readily takes fire, and continues to burn for some time like a piece of bad turf. In like manner, a mixture of tin and zinc, when strongly heated, decomposes both moist air and steam with rapidity.

 

The specific gravity of alloys is rarely

 

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the arithmetical mean of that of their constituents, as commonly taught; and in many cases considerable condensation or expansion occurs. When there is a strong affinity between two metals, the density of their alloy is generally greater than the calculated mean; and vice versa, as may be seen in the following table:

 

ALLOYS HAVING A DENSITY

Greater than the Mean of their Constituents:

 

Copper and bismuth,

Copper and palladium,

Copper and tin,

Copper and zinc,

Gold and antimony,

Gold and bismuth,

Gold and cobalt,

Gold and tin,

Gold and zinc,

Lead and antimony,

Palladium and bismuth,

Silver and antimony,

Silver and bismuth,

Silver and lead,

Silver and tin,

Silver and zinc.

 

Less than the Mean of their Constituents:

 

Gold and copper,

Gold and iridium,

Gold and iron,

Gold and lead,

Gold and nickel,

Gold and silver,

Iron and antimony,

Iron and bismuth,

Iron and lead,

Nickel and arsenic,

Silver and copper,

Tin and antimony,

Tin and lead,

Tin and palladium,

Zinc and antimony.

 

Compounding Alloys. Considerable experience is necessary to insure success in compounding alloys, especially when the metals employed vary greatly in fusibility and volatility. The following are rules supplied by an experienced workman:

 

1. Melt the least fusible, oxidizable, and volatile first, and then add the others heated to their point of fusion or near it. Thus, if it is desired to make an alloy of exactly 1 part of copper and 3 of zinc, it

will be impossible to do so by putting proportions of the metals in a crucible and exposing the whole to heat. Much of the zinc would fly off in vapor before the copper was melted. First, melt the copper and add the zinc, which has been melted in another crucible. The zinc should be in excess, as some of it will be lost anyway.

 

2. Some alloys, as copper and zinc, copper and arsenic, may be formed by exposing heated plates of the least fusible metal to the vapor of the other. In making brass in the large way, thin plates of copper are dissolved, as it were, in melted zinc until the proper proportions have been obtained.

 

3. The surface of all oxidizable metals should be covered with some protecting agent, as tallow for very fusible ones, rosin for lead and tin, charcoal for zinc, copper, etc.

 

4. Stir the metal before casting and if possible, when casting, with a white-wood stick; this is much better for the purpose than an iron rod.

 

5. If possible, add a small portion of old alloy to the new. If the alloy is required to make sharp castings and strength is not a very great object, the proportion of old alloy to the new should be increased. In all cases a new or thoroughly well-cleansed crucible should be used.

 

To obtain metals and metallic alloys from their compounds, such as oxides, sulphides, chlorides, etc., a process lately patented makes use of the reducing qualities of aluminum or its alloys with magnesium. The finely powdered material (e. g., chromic oxide) is placed in a crucible mixed with aluminum oxide. The mixture is set afire by means of a soldering pipe or a burning magnesium wire, and the desired reaction takes place. For igniting, one may also employ with advantage a special priming cartridge consisting of pulverized aluminum to which a little magnesium may be mixed, and peroxide of magnesia, which is shaped into balls and lighted with a magnesium wire. By suitable additions to the pulverized mixture, alloys containing aluminum, magnetism, chromium, manganese, copper, iron, boron, silicic acid, etc., are obtained.

 

ALUMINUM ALLOYS.

 

M. H. Pecheux has contributed to the Comptes Rendus, from time to time, the results of his investigations into the alloys of aluminum with soft metals, and the following constitutes a brief summary of his observations:

 

Lead. When aluminum is melted and lead is added in proportion greater than 10 per cent, the metals separate on cooling into three layers lead, aluminum, and between them an alloy containing from 90 to 97 per cent of aluminum.

 

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The alloys with 93, 95, and 98 per cent have densities of 2.745, 2.674, and 2.600 respectively, and melting points near that of aluminum. Their color is like that of aluminum, but they are less lustrous. All are malleable, easily cut, softer than aluminum, and have a granular fracture. On remelting they become somewhat richer in lead, through a tendency to liquation. They do not oxidize in moist air, nor at their melting points. They are attacked in the cold by hydrochloric and by strong sulphuric acid, with evolution of hydrogen, and by strong nitric

acid when hot; strong solution of potassium hydroxide also attacks them. They are without action on distilled water, whether cold or hot.

 

Zinc. Well-defined alloys were obtained, corresponding to the formulas

Zn₃Al, Zn₂Al, ZnAl, ZnAl₂ , ZnAl₃, ZnAl₄, ZnAl₆,ZnAl₁₀ , ZnAl₁₂ . Their melting points and densities all lie between those of zinc and aluminum, and those containing most zinc are the hardest. They are all dissolved by cold hydrochloric acid and by hot dilute nitric acid. Cold concentrated nitric acid attacks the first three, and cold dilute acid the first five. The Zn₃Al, ZnAl₆ , ZnAl₁₀, and ZnAl₁₂ are only slightly affected by cold potassium-hydroxide solution; the others are strongly attacked, potassium zincate and aluminate probably being formed.

 

Tin. A filed rod of tin-aluminum alloy plunged in cold water gives off for some minutes bubbles of gas, composed of hydrogen and oxygen in explosive proportions. An unfiled rod, or a filed rod of either aluminum or tin, is without action, though the unfiled rod of alloy will act on boiling water. The filed rod of alloy, in faintly acid solution of copper or zinc sulphate, becomes covered with a deposit of copper or zinc, while bubbles of oxygen are given off. M. Pecheux believes that the metals are truly alloyed only at the surface, and that filing lays bare an almost infinitely numerous series of junctions of the two metals, which, heated by the filing, act as thermocouples.

 

Bismuth. By the method used for lead, bismuth alloys were obtained con-

taining 75, 85, 88, and 94 per cent of aluminum, with densities 2.86, 2.79, 2.78. and 2.74 respectively. They were sonorous, brittle, finely grained, and homogeneous, silver-white, and with melting points between those of their constituents, but nearer that of aluminum. They are not oxidized in air at the temperature of casting, but are readily attacked by acids, concentrated or dilute, and by potassium-hydroxide solution.

The filed alloys behave like those of tin, but still more markedly.

 

Magnesium. These were obtained with 66, 68, 73, 77, and 85 per cent of aluminum, and densities 2.24, 2.47, 2.32, 2.37, 2.47. They are brittle, with large granular fracture, silver-white, file well, take a good polish, and have melting points near that of aluminum. Being viscous when melted, they are difficult to cast, and when slowly cooled form a gray, spongy mass which cannot be remelted. They do not oxidize in air at the ordinary temperatures, but burn readily at a bright-red heat. They are attacked violently by acids and by potassium-hydroxide solution, decompose hydrogen peroxide, and slowly decompose water even in the cold.

 

Tin, Bismuth, and Magnesium. The action of water on these alloys just referred to has been recently demonstrated on a larger scale, 5 to 6 cubic centimeters of hydrogen having been obtained in 20 minutes from 2 cubic centimeters of the filed tin alloy. The bismuth alloy yielded more hydrogen than the tin alloy, and the magnesium alloy more than the bismuth alloy. The oxygen of the decomposed water unites with the aluminum. Larger quantities of hydrogen are obtained from copper-sulphate solution, apart from the decomposition of this solution by precipitation of copper at the expense of the metal alloyed with the aluminum. The alloys of aluminum with zinc and lead do not decompose pure water, but do decompose the water of copper-sulphate solution, and, more slowly, that of zinc-sulphate solution.

 

Aluminum is a metal whose properties are very materially influenced by a proportionately small addition of copper. Alloys of 99 per cent aluminum and 1 per cent of copper are hard, brittle, and bluish in color; 95 per cent of aluminum and 5 per cent of copper give an alloy which can be hammered, but with 10 per cent of copper the metal can no longer be worked. With 80 per cent and upward of copper are obtained alloys of a beautiful yellow color, and these mixtures, containing from

5 to 10 percent of aluminum and from 90 to 95 per cent of copper, are the genuine aluminum bronzes. The 10-per-cent alloys are of a pure golden-yellow color; with 5 per cent of aluminum they are reddish yellow, like gold heavily alloyed with copper, and a 2-per-cent admixture is of an almost pure copper red.

 

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As the proportion of copper increases, the brittleness is diminished, and alloys containing 10 per cent and less of aluminum can be used for industrial purposes, the best consisting of 90 per cent of copper and 10 of aluminum. The hardness of this alloy approaches that of the general bronzes, whence its name. It can be stretched out into thin sheets between rollers, worked under the hammer, and shaped as desired by beating or pressure, in powerful stamping presses. On account of its hardness it takes a fine polish, and its peculiar greenish-gold color resembles that of gold alloyed with copper and silver together.

 

Alloys with a still greater proportion of copper approach this metal more and more nearly in their character; the color of an alloy, for instance, composed of 95 per cent of copper and 5 per cent of aluminum, can be distinguished from pure gold only by direct comparison, and the metal is very hard, and also very malleable.

 

Electrical Conductivity of Aluminum Alloys. During three years' exposure to the atmosphere, copper-aluminum alloys in one test gradually diminished in conductivity in proportion to the amount of copper they contained. The nickel-copper aluminum alloys, which show such remarkably increased tensile strength as compared with good commercial aluminum, considerably diminished in total conductivity. On the other hand, the manganese-copper aluminum alloys suffered comparatively little diminution in total conductivity, and one of them retained comparatively high tensile strength. It was thought that an examination of the structure of these alloys by aid of microphotography might throw some light on the great difference which exists between some of their physical properties. For instance, a nickel-copper aluminum alloy has 1.6 times the tensile strength of ordinary commercial aluminum. Under a magnification of 800 diameters practically no structure could be discovered. Considering the remarkable crystalline structure exhibited by ordinary commercial aluminum near the surface of an ingot, when allowed to solidify at an ordinary rate, the want of structure in these alloys must be attributed to the process of drawing down. The inference is that the great difference which exists between their tensile strengths and other qualities is not due to variation in structure.

 

Colored Alloys of Aluminum. A purple scintillating composition is produced by an alloyage of 78 parts of gold and 22 parts aluminum. With platinum a gold-colored alloy is obtained; with palladium a copper-colored one; and with cobalt and nickel one of a yellow color. Easily fusible metals of the color of aluminum give white alloys. Metal difficult of fusion, such as iridium, osmium, titanium, etc., appear in abnormal tones of color through such alloyages.

 

Aluminum-Brass. Aluminum, 1 per cent; specific gravity, 8.35 ; tensile trength, 40. Aluminum, 3 per cent; specific gravity, 8.33; tensile strength, 65. The last named is harder than the first.

 

Aluminum-Copper. Minikin is principally aluminum with a small percentage of copper and nickel. It is alloyed by mixing the aluminum and copper, then adding the nickel. It resembles palladium and is very strong.

 

Aluminum - Silver.

 

I.    Silver, 3 per cent; aluminum, 97 per cent. A handsome color.

 

II.   A silver aluminum that is easily worked into various articles contains about one-fourth silver and three-fourths of aluminum.

 

Aluminum-Tin. Bourbon metal is composed of equal parts of aluminum and tin; it solders readily.

 

Aluminum -Tungsten. A new metal alloy consisting of aluminum and tungsten is used of late in France in the (construction of conveyances, especially (Carriages, bicycles, and motor vehicles. The French call it partinium; the composition of the new alloy varies according to the purposes for which it is used. It is considerably cheaper than aluminum, almost as light, and has a greater resistance. The strength is stated at 32 to 37 kilograms per square millimeter.

 

Aluminum-Zinc. Zinc, 3 per cent: aluminum, 97 per cent. Very ductile, white, and harder than aluminum.

 

AMALGAMS:

See Fusible Alloys.

 

Anti-Friction Bearing or Babbitt Metals. These alloys are usually supported by bearings of brass, into which it is poured after they have been tinned, and heated and put together with an exact model of the axle, or other working piece, plastic clay being previously applied, in the usual manner, as a lute or outer mold. Soft gun metal is also excellent, and is much used for bearings. They all become less heated in working than the

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