(5) Common heavy shop oil. 30 pints petroleum, 20 of crude paraffin-oil, 20 of lard-oil, 9 of palm-oil, 20 of cottonseed-oil.

(6) Frazer's axle-grease is composed of partially saponified rosin-oil-that is, a rosin-soap and rosin-oil. In its preparation, 1/2 gal. of No. 1 and 2 1/2 gal. of No. 4 rosin-oil are saponified with a solution of 1/2 lb. sal-soda dissolved in 3 pints water and 10 lb. sifted lime. After standing for 6 hours or more, this is drawn off from sediment, and thoroughly mixed with 1 gal. of No. 1, 3} gal. No. 2, and 4] gal. No. 3 rosin-oil. This rosin-oil is obtained by the destructive distillation of common rosin, the products ranging from an extremely light to a heavy fluorescent oil or colophonic tar.

(7) Pitt's car-, mill-, and axle-grease is prepared as follows:-

Black oil or petroleum residue

40

gal.

Animal grease ......

50

lb.

Rosin powdered ......

60

lb.

Soda lye ...........

2 1/4

gal.

Salt, dissolved in a little water 5 lb.

All but the lye are mixed together, and heated to about 250° F. (121° C). The lye is then gradually stirred in, and in about 24 hours the compound is ready for use.

(8) Hendricks' lubricant is prepared from whale- or fish-oil, white-lead, and petroleum. The oil and white-lead are, in about equal quantities, stirred and gradually heated to between 350° and 400° F. (177° to 204 1/2° C), then mixed with a sufficient quantity of the petroleum to reduce the mixture to the proper gravity.

(9) Hunger's preparation consists of-

Petroleum ...........

1

gal

Tallow..

4

oz.

Palm oil ......

4

oz.

Graphite.....

6

oz.

Soda........

1

oz.

These are mixed and heated to 180° F. (82° C.) for an hour or more, cooled, and after 24 hours well stirred together.

(10) A somewhat similar compound is prepared by Johnson as follows:-

Liquid.

Solid

Petroleum (30° to 37° gravity ) .......

1

gal.

1

gal

Crude paraffin ..

1

DZ.

2

OZ.

Wax (myrtle, Japan and gambier) .......

1 1/2

OZ.

7

oz.

Bicarbonate of soda ..

l

oz.

1

oz.

Powdered graphite 3 to 5 oz.

8

oz.

(11) Maguire uses for hot neck grease-

Tallow....

16

lb.

Fish ......

60

lb.

Soapstone ........

12

lb.

Graphite..............

9

lb.

Saltpetre.......

2

lb.

The fish (whole) is steamed, macerated, and the jelly pressed through fine sieves for use with the other constituents.

(12) Chard's preparation for heavy bearings consists of Petroleum (gravity 25°).. 12 oz. Caoutchouc ...... 2 oz.

(13) Booth's. 1/2 lb. soda, 1 gal. rape-seed-oil, 1 gal. water, 1/2 lb. tallow or palm-oil; mix intimately, heat to boiling, and continue stirring till cooled down to 60° or 70° F. (15 1/2° to 21° C).

(14) 1 gal. boiling water, 1/2 lb. Scotch soda, 10 lb. of a mixture of palm-oil and tallow in any proportions; treat as (13).

(15) 10 lb. Scotch soda, 1 lb. glue dissolved in 10 gal. water, 10 gal. oil, 4 lb. indiarubber dissolved in oil of turpentine; add the indiarubber last, and stir the whole thoroughly.

(16) 2 1/2 lb. lard, 1 oz. camphor, 1/2 lb. graphite ("black lead"). Rub up the camphor into a paste with part of the lard in a mortar, add the graphite and the rest of the lard, and intimately mix.

(17) Dissolve 2} lb. sugar of lead (lead acetate) in 161b. melted.but not boiling tallow, and add 3 lb. black antimony, stirring the mixture constantly till cold. For cooling necks of shafts.

(18) 4 lb. tallow, 1 lb. graphite, ground together till quite smooth, adding 3 lb. to 5 lb. camphor per cwt.

(19) Railway-Grease

For summer use-1 3/4 cwt. tallow, 1 1/4 cwt. palm-oil; for autumn and spring-1 1/2 cwt. each tallow and palm-oil; for winter-1 1/4 cwt. tallow, 1 3/4 cwt. palm-oil. Melt the tallow in an open pan, add the palm-oil, and remove the fire the moment the mixture boils; stir frequently while cooling, and when the temperature has fallen to about 100° F. (38o C), run it through a sieve into a solution of soda (56 to 60 lb.) in 3 gal. water, and stir together thoroughly.

(20) To a quantity of good lard, rendered semi-fluid (but not liquid) by gentle heat in an iron pan, is gradually added 1/5 part by weight of finely powdered and sifted graphite (black-lead), with careful and continued stirring till the mass is homogeneous and smooth; the heat is then steadily increased till the compound liquefies, when it is allowed to cool, the stirring having been meanwhile kept up unceasingly.

(21) 8 lb. tallow, 10 lb. palm-oil, 1 lb. graphite (blacklead).

(22) Watchmakers' Oil

Olive-oil containing a strip of clean lead is exposed to the sun in a white glass vessel till all deposit ceases, and the.supernatant oil is limpid and colourless.

(23) Oleine for lubricating fine mechanism is prepared by agitating almond-or olive-oil with 7 or 8 times its weight of strong alcohol (sp. gr. 0.798) at nearly boiling-point; the solution is allowed to cool, and the clear fluid is decanted, filtered, and heated to drive off the alcohol. It may further be exposed to a low temperature to deposit any remaining stearine.

(24) Railway- And Waggon-Grease

The first of these consists essentially of a mixture of a more or less perfectly formed soap, water, carbonate of soda, and neutral fat, and is used on the axles of all locomotives, railway-carriages, and trucks that are provided with axle-boxes; while the second is a soap of lime and rosin-oil, with or without water, and is used on all rail way-trucks unprovided with axle-boxes, and for ordinary road vehicles.

The requisites for a good "locomotive-grease" for high velocities are: (1) a suitable consistency, such that it will neither run away too rapidly, nor be too stiff to. cool the axles; (2) lasting power, so that there may be as little increase of temperature as possible in the axles, even at high speeds; (3) a minimum of residue in the axle-boxes.

In practice, it is found that a grease containing 1.1 to 1-2 Per cent. soda (100 per cent.) gives the best result. The process of manufacture is very simple; Morfit's soap-pans, provided with stirrers, are the most suitable vessels for the purpose. The fats, usually tallow and palm-oil, are heated to 180° F. (82° C), and into them are run the carbonate of soda and water heated to 200°; F. (93 1/2° C); the whole is well stirred together, and run into large tubs to cool slowly. Many railway companies buy -a curd-soap made from red palm-oil, dissolve it in water, and add thereto enough tallow and water to bring the composition of the whole to the desired point. It is usual to allow 21 Per cent. for loss by evaporation of the water during the manufacture. The composition has to be slightly varied according to the season of the year; the following formulae for mixing have stood the test of successful experiment; the summer one ran 1200 miles. It should be carefully borne in mind that a careful analysis of locomotive-grease is no test whatever of its practical value, which can only be determined by actual experiment.