Russian Leather.
—This leather owes its name to the country of its origin. The skins used for its production are goat, large sheep, calfskin, and cow or steer hide. The preliminary operations of soaking, unhairing, and fleshing are done in the usual manner, and then the hides are permitted to swell in a mixture of rye flour, oat flour, yeast, and salt. This compound is made into a paste with water, and is then thinned with sufficient water to steep a hundred hides in the mixture. The proportions of ingredients used for this mixture are 22 pounds rye flour, 10 pounds oat flour, a little salt, and sufficient yeast to set up fermentation.

The hides are steeped in this compound for 2 days, until swelled up, and then put into a solution of willow and poplar barks, in which they are allowed to remain 8 days, being frequently turned about. The tanning process is then completed by putting them into a tanning liquor composed of pine and willow barks, equal parts. They are steeped 8 days in this liquor, and then a {455} fresh liquor of the same ingredients and proportions is made up. The hides are hardened and split, and then steeped in the freshly made liquor for another 8 days, when they are sufficiently tanned.

The hides are then cut down the middle (from head to tail) into sides, and scoured, rinsed, and dried by dripping, and then passed on to the currier, who slightly dampens the dry sides and puts them in a heap or folds them together for a couple of days to temper, and then impregnates them with a compound consisting of 2/3 parts birch oil and 1/3 parts seal oil. This is applied on the flesh side for light leather, and on the grain side also for heavy leather. The leather is then “set out,” “whitened,” and well boarded and dried before dyeing.

A decoction of sandalwood, alone or mixed with cochineal, is used for producing the Russian red color, and this dye liquor is applied several times, allowing each application to dry before applying the following one. A brush is used, and the dye liquor is spread on the grain side. A solution of tin chloride is used in Russia as a mordant for the leather before laying on the dye. The dye liquor is prepared by boiling 18 ounces of sandalwood in 13 pints of water for 1 hour, and then filtering the liquid and dissolving in the filtering fluid 1 ounce of prepared tartar and soda, which is then given an hour’s boiling and set aside for a few days before use.

After dyeing, the leather is again impregnated with the mixture of birch and seal oils (applied to the grain side on a piece of flannel) and when the dyed leather has dried, a thin smear of gum-dragon mucilage is given to the dyed side to protect the color from fading, while the flesh side is smeared with bark-tan juice and the dyed leather then grained for market.

Toughening Leather.
—Leather is toughened and also rendered impervious by impregnating with a solution of 1 part of caoutchouc or gutta-percha in 16 parts of benzene or other solvent, to which is added 10 parts of linseed oil. Wax and rosin may be added to thicken the solution.
Painting On Leather.
—When the leather is finished in the tanneries it is at the same time provided with the necessary greasy particles to give it the required pliancy and prevent it from cracking. It is claimed that some tanners strive to obtain a greater weight thereby, thus increasing their profit, since a pound of fat is only one-eighth as dear as a pound of leather.

If such leather, so called kips, which are much used for carriage covers and knee caps, is to be prepared for painting purposes, it is above all necessary to close up the pores of the leather, so that the said fat particles cannot strike through. They would combine with the applied paint and prevent the latter from drying, as the grease consists mainly of fish oil. For this reason an elastic spirit leather varnish is employed, which protects the succeeding paint coat sufficiently from the fat.

For further treatment take a good coach varnish to which 1/4 of stand oil (linseed oil which has thickened by standing) has been added and allow the mixture to stand for a few days. With this varnish grind the desired colors, thinning them only with turpentine oil. Put on 2 coats. In this manner the most delicate colors may be applied to the leather, only it is needful to put on pale and delicate shades several times. In some countries the legs or tops of boots are painted yellow, red, green, or blue in this manner. Inferior leather, such as sheepskin and goat leather, which is treated with alum by the tanner, may likewise be provided with color in the manner stated. Subsequently it can be painted, gilded, or bronzed.

Stains For Oak Leather.
—I.—Apply an intimate mixture of 4 ounces of umber (burnt or raw); 1/2 ounce of lampblack, and 17 fluidounces ox gall.

II.—The moistened leather is primed with a solution of 1 part, by weight, of copper acetate in 50 parts of water, slicked out and then painted with solution of yellow prussiate potash in feebly acid water.

LEMONS:

See also Essences, Extracts, and Fruits.

Preservation Of Fresh Lemon Juice.

—The fresh juice is cleared by gently heating it with a little egg albumen, without stirring the mixture. This causes all solid matter to sink with the coagulated white, or to make its way to the surface. The juice is then filtered through a woolen cloth and put into bottles, filled as full as possible, and closed with a cork stopper, in such a way that the cork may be directly in contact with the liquid. Seal at once and keep in a cool place. The bottles should be asepticized with boiling water just before using.

LENSES AND THEIR CARE:

Unclean Lenses

(see also Cleaning Preparations and Methods).—If in either objective or eyepiece the lenses are not clean, the definition may be seriously impaired or destroyed. Uncleanliness may be due to finger marks upon the front lens of the objective, or upon the eyepiece lenses; dust which in time may settle upon the rear lens of the objective or on the eye lens; a film which forms upon one or the other lens, due occasionally to the fact that glass is hygroscopic, but generally to the exhalation from the interior finish of the mountings, and, in immersion objectives, because the front lens is not properly cleaned; or oil that has leaked on to its rear surface, or air bubbles that have formed in the oil between the cover glass and front lens.

Remedy.—Keep all lenses scrupulously clean. For cleaning, use well-washed linen (an old handkerchief) or Japanese lens paper.

Eyepieces.—To find impurities, revolve the eyepieces during the observation; breathe upon the lenses, and wipe gently with a circular motion and blow off any particles which may adhere.

Dry Objectives.—Clean the front lens as described. To examine the rear and interior lenses use a 2-inch magnifier, looking through the rear. Remove the dust from the rear lens with a camel’s-hair brush.

Oil Immersion Objectives.—Invariably clean the front lens after use with moistened linen or paper, and wipe dry.

In applying oil examine the front of the objective with a magnifier, and if there are any air bubbles, remove them with a pointed quill, or remove the oil entirely and apply a fresh quantity.

LETTERING

Gold Lettering.

—This is usually done by first drawing the lettering, then covering with an adhesive mixture, such as size, and finally applying gold bronze powder or real gold leaf. A good method for amateurs to follow in marking letters on glass is to apply first a coat of whiting, mixed simply with water, and then to mark out the letters on this surface, using a pointed stick or the like. After this has been done the letters may easily be painted or gilded on the reverse side of the glass. When done, wash off the whiting from the other side, and the work is complete.

Bronze Lettering.

—The following is the best method for card work: Write with asphaltum thinned with turpentine until it flows easily, and, when nearly dry, dust bronze powder over the letters. When the letters are perfectly dry tap the card to take off the extra bronze, and it will leave the letters clean and sharp. The letters should be made with a camel’s-hair brush and not with the automatic pen, as oil paints do not work satisfactorily with these pens.

For bronzed letters made with the pen, use black letterine or any water color. {457} If a water color is used add considerable gum arabic. Each letter should be bronzed as it is made, as the water color dries much more quickly than the asphaltum.

Another method is to mix the bronze powder with bronze sizing to about the consistency of the asphaltum. Make the letter with a camel’s-hair brush, using the bronze paint as one would any oil paint.

This method requires much skill, as the gold paint spreads quickly and is apt to flood over the edge of the letter. For use on oilcloth this is the most practical method.

Bronzes may be purchased at any hardware store. They are made in copper, red, green, silver, gold, and copper shades.

Lettering On Glass.

—White lettering on glass and mirrors produces a rich effect. Dry zinc, chemically pure, should be used. It can be obtained in any first-class paint store and is inexpensive. To every teaspoonful of zinc, 10 drops of mucilage should be added. The two should be worked up into a thick paste, water being gradually added until the mixture is about the consistency of thick cream. The paint should then be applied with a camel’s-hair brush.

Another useful paint for this purpose is Chemnitz white. If this distemper color is obtained in a jar, care should be exercised to keep water standing above the color to prevent drying. By using mucilage as a sizing these colors will adhere to the glass until it is washed off. Both mixtures are equally desirable for lettering on block card-board.

Any distemper color may be employed on glass without in any way injuring it. An attractive combination is—first to letter the sign with Turkey red, and then to outline the letters with a very narrow white stripe. The letter can be rendered still more attractive by shading one side in black.

Signs On Show Cases.

—Most show cases have mirrors at the back, either in the form of sliding panels or spring doors. Lettering in distemper colors on these mirrors can easily be read through the fronts or tops of cases. If the mirror is on a sliding panel, it will be necessary to detach it from the case in order to letter it. When the mirror is on a spring door the sign can be lettered with less trouble.

By tracing letters in chalk on the outside of the glass, and then painting them on the inside, attractive signs can be produced on all show cases; but painting letters on the inside of a show case glass is more or less difficult, and it is not advisable to attempt it in very shallow cases.

“Spatter” Work.

—Some lettering which appears very difficult to the uninitiated is, in fact, easily produced. The beautiful effect of lettering and ornamentation in the form of foliage or conventional scrolls in a speckled ground is simple and can be produced with little effort. Pressed leaves and letters or designs cut from newspapers or magazines may be tacked or pasted on cardboard or a mat with flour paste. As little paste as possible should be used—only enough to hold the design in place. When all the designs are in the positions desired, a toothbrush should be dipped in the ink or paint to be employed. A toothpick or other small piece of wood is drawn to and fro over the bristles, which are held toward the sign, the entire surface of which should be spattered or sprinkled with the color. When the color is dry the designs pasted on should be carefully removed and the paste which held them in place should be scraped off. This leaves the letters and other designs clean cut and white against the “spatter” background. The beginner should experiment first with a few simple designs. After he is able to produce attractive work with a few figures or letters he may confidently undertake more elaborate combinations.

Lettering On Mirrors.

—From a bar of fresh common brown soap cut off a one-inch-wide strip across its end. Cut this into 2 or 3 strips. Take one strip and with a table-knife cut from two opposite sides a wedge-shaped point resembling that of a shading pen, but allow the edge to be fully 1/8 inch thick. Clean the mirror thoroughly and proceed to letter in exactly the same manner as with a shading pen.

To Fill Engraved Letters On Metal Signs.

—Letters engraved on metal may be filled in with a mixture of asphaltum, brown japan, and lampblack, the mixture being so made as to be a putty-like mass. It should be well pressed down with a spatula. Any of the mass adhering to the plate about the edges of the letters is removed with turpentine, and when the cement is thoroughly dried the plate may be polished.

If white letters are desired, make a putty of dry white lead, with equal parts of coach japan and rubbing varnish. Fill the letters nearly level with the {458} surface, and when hard, apply a stout coat of flake white in japan thinned with turpentine. This will give a clean white finish that may be polished.

The white cement may be tinted to any desired shade, using coach colors ground in japan.

Tinseled Letters, Or Chinese Painting On Glass.

—This is done by painting the groundwork with any color, leaving the letter or figure naked. When dry, place tin foil or any of the various colored copper foils over the letters on the back of the glass, after crumpling them in the hand, and then partially straightening them out.

LICORICE:

Stable Solutions Of Licorice Juice.

—A percolator, with alternate layers of broken glass, which have been well washed, first with hydrochloric acid and plentifully rinsed with distilled water, is the first requisite. This is charged with pieces of crude licorice juice, from the size of a hazel nut to that of a walnut, which are weighted down with well-washed pebbles. The percolate is kept for 3 days in well corked flasks which have been rinsed out with alcohol beforehand. Decant and filter and evaporate down rapidly, under constant stirring, or in vacuo. The extract should be kept in vessels first washed with alcohol and closed with parchment paper, in a dry place—never in the cellar.

To dissolve this extract, use water, first boiled for 15 minutes. The solution should be kept in small flasks, first rinsed with alcohol and well corked. If to be kept for a long time, the flasks should be subjected for 3 consecutive days, a half hour each day, to a stream of steam, and the corks paraffined.

There is frequently met with in commerce a purified juice that remains clear in the mixtura solvens. It is usually obtained by supersaturation with pure ammonia, allowing to stand for 3 days, decanting, filtering the decanted liquor, and quick evaporation. Since solutions with water alone rapidly spoil, it is well to observe with them the precautions common for narcotic extracts.

To Test Extract Of Licorice.

—Mere solubility is no test for the purity of extract of licorice. It is, therefore, proposed to make the glycyrrhizin content and the nature of the ash the determining test. To determine the glycyrrhizin quantitatively proceed as follows: Macerate 1/10 ounce of the extract, in coarse powder, in 10 fluidounces distilled water for several hours, with more or less frequent agitation. When solution is complete, add 10 fluidounces alcohol of 90 per cent, filter and wash the filter with alcohol of 40 per cent until the latter comes off colorless. Drive off the alcohol, which was added merely to facilitate filtration, by evaporation in the water bath; let the residue cool down and precipitate the glycyrrhizin by addition of sulphuric acid. Filter the liquid and wash the precipitate on the filter with distilled water until the wash water comes off neutral. Dissolve the glycyrrhizin from the filter by the addition of ammonia water, drop by drop, collecting the filtered solution in a tared capsule. Evaporate in the water bath, dry the residual glycyrrhizin at 212° F., and weigh. Repeated examinations of known pure extracts have yielded a range of percentage of glycyrrhizin running from 8.06 per cent to 11.90 per cent. The ash should be acid in reaction and a total percentage of from 5.64 to 8.64 of the extract.

LIME, BIRD.

Bird lime is a thick, soft, tough, and sticky mass of a greenish color, has an unpleasant smell and bitter taste, melts easily on heating, and hardens when exposed in thin layers to the air. It is difficult to dissolve in alcohol, but easily soluble in hot alcohol, oil of turpentine, fat oils, and also somewhat in vinegar. The best quality is prepared from the inner green bark of the holly (Ilex aquifolium), which is boiled, then put in barrels, and submitted for 14 days to slight fermentation until it becomes sticky. Another process of preparing it is to mix the boiled bark with juice of mistletoe berries and burying it in the ground until {459} fermented. The bark is then pulverized, boiled, and washed. Artificial bird lime is prepared by boiling and then igniting linseed oil, or boiling printing varnish until it is very tough and sticky. It is also prepared by dissolving cabinetmakers’ glue in water and adding a concentrated solution of chloride of zinc. The mixture is very sticky, does not dry on exposure to the air, and has the advantage that it can be easily washed off the feathers of the birds.

LINIMENTS:

See also Ointments.

For External Use Only.

—I.—The following penetrating oily liniment reduces all kinds of inflammatory processes:
Paraffine oil 4 ounces
Capsicum powder   1/2 ounce

Digest on a sand bath and filter. To this may be added directly the following: Oil of wintergreen or peppermint, phenol, thymol, camphor or eucalyptol, etc.

II.— Camphor 2 ounces
Menthol 1 ounce
Oil of thyme 1 ounce
Oil of sassafras 1 ounce
Tincture of myrrh 1 ounce
Tincture of capsicum 1 ounce
Chloroform 1 ounce
Alcohol 2 pints

LINOLEUM:

See also Oilcloth.

Composition For Linoleum, Oilcloth, Etc.

—This is composed of whiting, dried linseed oil, and any ordinary dryer, such as litharge, to which ingredients a proportion of gum tragacanth is to be added, replacing a part of the oil and serving to impart flexibility to the fabric, and to the composition a pasty mass the property of drying more rapidly. In the production of linoleum, the whiting is replaced in whole or in part by pulverized cork. The proportions are approximately the following by weight: Whiting or powdered cork, 13 parts; gum tragacanth, 5 parts; dried linseed oil, 5 1/2 parts; siccative, 1/2 part.

Dressings For Linoleum.

—A weak solution of beeswax in spirits of turpentine has been recommended for brightening the appearance of linoleum. Here are some other formulas:
I.— Palm oil  1 ounce
Paraffine 18 ounces
Kerosene  4 ounces

Melt the paraffine and oil, remove from the fire and incorporate the kerosene.

II.— Yellow wax  5 ounces
Oil turpentine 11 ounces
Amber varnish  5 ounces

Melt the wax, add the oil, and then the varnish. Apply with a rag.

Treatment Of Newly Laid Linoleum.

—The proper way to cleanse a linoleum flooring is first to sweep off the dust and then wipe up with a damp cloth. Several times a year the surface should be well rubbed with floor wax. Care must be had that the mass is well pulverized and free from grit. Granite linoleum and figured coverings are cleansed without the application of water. A floor covering which has been treated from the beginning with floor wax need only be wiped off daily with a dry cloth, either woolen or felt, and afterwards rubbed well with a cloth filled with the mass. It will improve its appearance, too, if it be washed several times a year with warm water and a neutral soap.

LINSEED OIL:

See also Oils.

Bleaching Of Linseed Oil And Poppyseed Oil.

—In order to bleach linseed oil and poppyseed oil for painting purposes, thoroughly shake 2.5 parts of it in a glass vessel with a solution of potassium permanganate, 50 parts, in 1,250 parts of water; let stand for 24 hours in a warm temperature, and then mix with 75 parts of pulverized sodium sulphite. Now shake until the latter has dissolved and add 100 parts of crude hydrochloric acid, 20°. Agitate frequently and wash, after the previously brown mass has become light colored, with water, in which a little {460} chalk has been finely distributed, until the water is neutral. Finally filter over calcined Glauber’s salt.

Adulteration Of Linseed Oil.

—This is common, and a simple and cheap method of testing is by nitric acid. Pour equal parts of the linseed oil and nitric acid into a flask, shake vigorously, and let it stand for 20 minutes. If the oil is pure, the upper stratum is of straw yellow color and the lower one colorless. If impure, the former is dark brown or black, the latter pale orange or dark yellow, according to the admixtures to the oil.

The addition of rosin oil to linseed oil or other paint oils can be readily detected by the increase in specific gravity, the low flash point, and the odor of rosin on heating; while the amount may be approximately ascertained from the amount of unsaponifiable oil left after boiling with caustic soda.

LUBRICANTS

Oil For Firearms.

—Either pure vaseline oil, white, 0.870, or else pure white-bone oil, proof to cold, is employed for this purpose, since these two oils are not only free from acid, but do not oxidize or resinify.

Leather Lubricants.

—Russian tallow, 1 pound; beeswax, 6 ounces; black pitch, 4 ounces; common castor oil, 3 pounds; soft paraffine, 1/2 pound; oil of citronella, 1/2 ounce. Melt all together in a saucepan, except the citronella, which add on cooling. Stir occasionally.

Machinery Oils.

—I.—The solid fat, called bakourine, a heavy lubricant which possesses extraordinary lubricating qualities has a neutral reaction and melts only at about 176° to 188° F. It is prepared as follows:

A mixture is made of 100 parts of Bienne petroleum or crude naphtha, with 25 parts of castor oil or some mineral oil, and subjected to the action of 60 or 70 parts of sulphuric acid of 66° Bé. The acid is poured in a small stream into the oil, while carefully stirring. The agitation is continued until a thick and blackish-brown mass is obtained free from non-incorporated petroleum. Very cold water of 2 or 3 times the weight of the mass is then added, and the whole is stirred until the mass turns white and becomes homogeneous. It is left at rest for 24 hours, after which the watery liquid, on the surface of which the fat is floating, must be poured off. After resting again from 3 to 4 days, the product is drawn off, carefully neutralized with caustic potash, and placed in barrels ready for shipping.

II.—Melt in a kettle holding 2 to 4 times as much as the volume of the mass which is to be boiled therein, 10 parts, by weight, of tallow in 20 parts of rape oil on a moderate fire; add 10 parts of freshly and well burnt lime, slaked in 30 or 40 parts of water; increase the fire somewhat, and boil with constant stirring until a thick froth forms and the mass sticks to the bottom of the kettle. Burning should be prevented by diligent stirring. Then add in portions of 10 parts each, gradually, 70 parts of rape oil and boil with a moderate fire, until the little lumps gradually forming have united to a whole uniform mass. With this operation it is of importance to be able to regulate the fire quickly. Samples are now continually taken, which are allowed to cool quickly on glass plates. The boiling down must not be carried so far that the samples harden on cooling; they must spin long, fine threads, when touched with the finger. When this point is reached add, with constant stirring, when the heat has abated sufficiently (which may be tested by pouring in a few drops of water), 25 to 30 parts of water. Now raise the fire, without {461} ceasing to stir, until the mass comes to a feeble, uniform boil. In order to be able to act quickly in case of a sudden boiling over, the fire must be such that it can be removed quickly, and a little cold water must always be kept on hand. Next, gradually add in small portions, so as not to disturb the boiling of the mass, 500 parts of paraffine oil (if very thick, 800 to 900 parts may be added), remove from the fire, allow the contents of the kettle to clarify, and skim off the warm grease from the sediment into a stirring apparatus. Agitate until the mass begins to thicken and cool; if the grease should still be too solid, stir in a little paraffine oil the second time. The odor of the paraffine oil may be disguised by the admixture of a little mirbane oil.

For Cutting Tools.

—The proportion of ingredients of a lubricating mixture for cutting tools is 6 gallons of water, 3 1/2 pounds of soft soap, and 1/2 gallon of clean refuse oil. Heat the water and mix with the soap, preferably in a mechanical mixer; afterwards add the oil. A cast-iron circular tank to hold 12 gallons, fitted with a tap at the bottom and having three revolving arms fitted to a vertical shaft driven by bevels and a fast and loose pulley, answers all requirements for a mixer. This should be kept running all through the working day.

For Highspeed Bearings.

—To prevent heating and sticking of bearings on heavy machine tools due to running continuously at high speeds, take about 1/8 of flake graphite, and the remainder kerosene oil. As soon as the bearing shows the slightest indication of heating or sticking, this mixture should be forcibly squirted through the oil hole until it flows out between the shaft and bearing, when a small quantity of thin machine oil may be applied.

For Heavy Bearings.

—An excellent lubricant for heavy bearings can be made from either of the following recipes:
I.— Paraffine  6 pounds
Palm oil 12 pounds
Oleonaphtha  8 pounds
II.— Paraffine  8 pounds
Palm oil 20 pounds
Oleonaphtha 12 pounds

The oleonaphtha should have a density of 0.9. First dissolve the paraffine in the oleonaphtha at a temperature of about 158° F. Then gradually stir in the palm oil a little at a time. The proportions will show that No. II gives a less liquid product than No. I. Quicklime may be added if desired.

For Lathe Centers.

—An excellent lubricant for lathe centers is made by using 1 part graphite and 4 parts tallow thoroughly mixed.

Sewing Machine Oil.

—I.—Petroleum oils are better adapted for the lubrication of sewing machines than any of the animal oils. Sperm oil has for a long time been considered the standard oil for this purpose, but it is really not well adapted to the conditions to which a sewing machine is subjected. If the machine were operated constantly or regularly every day, probably sperm oil could not be improved on. The difficulty is, however, that a family sewing machine will frequently be allowed to stand untouched for weeks at a time and will then be expected to run as smoothly as though just oiled. Under this kind of treatment almost any oil other than petroleum oil will become gummy. What is known in the trade as a “neutral” oil, of high viscosity, would probably answer better for this purpose than anything else. A mixture of 1 part of petrolatum and 7 parts of paraffine oil has also been recommended.
II.— Pale oil of almonds 9 ounces
Rectified benzoline 3 ounces
Foreign oil of lavender 1 ounce

Petroleum Jellies And Solidified Lubricants.

Petroleum jelly, vaseline, and petrolatum are different names for the same thing.

The pure qualities are made from American stock thickened with hot air until the desired melting point is attained. Three colors are made: white, yellow, and black of various qualities. Cheaper qualities are made by using ceresine wax in conjunction with the genuine article and pale mineral oil. This is the German method and is approved of by their pharmacopœia. Machinery qualities are made with cylinder oils, pale mineral oils, and ceresine wax.

I.— Yellow ceresine wax  11 parts
White ceresine wax   6 parts
American mineral oil, 903/907 151 parts

Melt the waxes and stir in the oil. To make white, use all white ceresine wax. To color, use aniline dyes soluble in oil to any shade required.

II.— Ceresine wax 1 pound
Bloomless mineral oil, Sq. 910 1 gallon

Melt the wax and add the oil, varying according to the consistency required. To color black, add 28 pounds lampblack to 20 gallons oil. Any wax will do, according to quality of product desired.

White Petroleum Jelly.—
White tasteless oil 4 parts
White ceresine wax 1 part
Solidified Lubricants.—
I.— Refined cotton oil   2 parts
American mineral oil, 903/907   2 parts
Oleate of alumina   1 part
Gently heat together.
II.— Petroleum jelly 120 parts
Ceresine wax   5 parts
Slaked lime     1/2 part
Water   4 1/2 parts

Heat the wax and the petroleum jelly gently until liquid; then mix together the water and lime. Decant the former into packing receptacles, and add lime and water, stirring until it sets. For cheaper qualities use cream cylinder oil instead of petroleum jelly.

Wagon And Axle Greases:

For Axles Of Heavy Vehicles.
—I.—Tallow (free from acid), 19 1/2 parts; palm oil, 14 parts; sal soda, 5 1/2 parts; water, 3 parts, by weight. Dissolve the soda in the water and separately melt the tallow, then stir in the palm oil. This may be gently warmed before adding, as it greatly facilitates its incorporation with the tallow, unless the latter be made boiling hot, when it readily melts the semi-solid palm oil. When these two greases are thoroughly incorporated, pour the mixture slowly into the cold lye (or soda solution), and stir well until the mass is homogeneous. This lubricant can be made less solid by decreasing the tallow or increasing the palm oil.

II.—Slaked lime (in powder), 8 parts, is slowly sifted into rosin oil, 10 parts. Stir it continuously to incorporate it thoroughly, and gently heat the mixture until of a syrupy consistency. Color with lampblack, or a solution of turmeric in a strong solution of sal soda. For blue grease, 275 parts of rosin oil are heated with 1 part of slaked lime and then allowed to cool. The supernatant oil is removed from the precipitated matter, and 5 or 6 parts of the foregoing rosin-oil soap are stirred in until all is a soft, unctuous mass.

For Axles Of Ordinary Vehicles.
—I.—Mix 80 parts of fat and 20 parts of very fine black lead; melt the fat in a varnished earthen vessel; add the black lead while constantly stirring until it is cold, for otherwise the black lead, on account of its density, would not remain in suspension in the melted fat. Axles lubricated with this mixture can make 80 miles without the necessity of renewing the grease.

II.—Mix equal parts of red American rosin, melted tallow, linseed oil, and caustic soda lye (of 1.5 density).

III.—Melt 20 parts of rosin oil in 50 parts of yellow palm oil, saponify this with 25 parts of caustic soda lye of 15° Bé., and add 25 parts of mineral oil or paraffine.

IV.—Mix residue of the distillation of petroleum, 60 to 80 parts; tallow, 10 parts; colophony, 10 parts; and caustic soda solution of 40° Bé., 15 parts.

A Grease For Locomotive Axles.
—Saponify a mixture of 50 parts tallow, 28 parts palm oil, 2 parts sperm oil. Mix in soda lye made by dissolving 12 parts of soda in 137 parts of water.

Miscellaneous Lubricants:

For Cotton Belts.
—Carefully melt over a slow fire in a closed iron or self-regulating boiler 250 parts of caoutchouc or gum elastic, cut up in small pieces; then add 200 parts of colophony; when the whole is well melted and mixed, incorporate, while carefully stirring, 200 parts of yellow wax. Then heat 850 parts of train oil, mixing with it 250 parts of talc, and unite the two preparations, constantly stirring, until completely cold.
Chloriding Mineral Lubricating Oils.
—A process has been introduced for producing industrial vaselines and mineral oils for lubrication, based on the treatment of naphthas, petroleums, and similar hydrocarbides, by means of chlorine or mixtures of chlorides and hypochlorides, known under the name of decoloring chlorides. Mix and stir thoroughly 1,000 parts of naphtha of about 908 density; 55 parts of chloride of lime, and 500 parts of water. Decant and wash.
Glass Stop Cock Lubricant.
—(See also Stoppers).
Pure rubber 14 parts
Spermaceti  5 parts
Petroleum  1 part

Melt the rubber in a covered vessel and then stir in the other ingredients. A little more petroleum will be required when the compound is for winter use. {463}

Hard Metal Drilling Lubricant.
—For drilling in hard metal it is recommended to use carbolic acid instead of another fatty substance as a lubricant, since the latter, by decreasing the friction, diminishes the “biting” of the drill, whereas the carbolic acid has an etching action.
Plaster Model Lubricant.
—Take linseed oil, 1,000 parts; calcined lead, 50 parts; litharge, 60 parts; umber, 30 parts; talc, 25 parts. Boil for 2 hours on a moderate fire; skim frequently and keep in well-closed flasks.
Graphite Lubricating Compound.
—Graphite mixed with tallow gives a good lubricating compound that is free from any oxidizing if the tallow be rendered free from rancidity. The proportions are: Plumbago, 1 part; tallow, 4 parts. The plumbago being stirred into the melted tallow and incorporated by passing it through a mixing mill, add a few pounds per hundredweight of camphor in powder to the hot compound.
Lubricants For Redrawing Shells.
—Zinc shells should be clean and free from all grit and should be immersed in boiling hot soap water. They must be redrawn while hot to get the best results. On some shells hot oil is used in preference to soap water.

For redrawing aluminum shells use a cheap grade of vaseline. It may not be amiss to add that the draw part of the redrawing die should not be made too long, so as to prevent too much friction, which causes the shells to split and shrivel up.

For redrawing copper shells use good thick soap water as a lubricant. The soap used should be of a kind that will produce plenty of “slip.” If none such is to be had, mix a quantity of lard oil with the soap water on hand and boil the two together. Sprinkling graphite over the shells just before redrawing sometimes helps out on a mean job.