Part 290

«Red Stain.»—Water, 1 quart; spirit of hartshorn, 1 quart; cochineal, 1⁠/⁠4 pound. Heat the water to near the boiling point, and then dissolve in it the cochineal, afterwards adding the spirit of hartshorn. Stir well to incorporate.

«Liquid Cochineal Stain.»—

Good French carmine 2 1⁠/⁠2 drachms Solution of potash 1⁠/⁠2 ounce Rectified spirit of wine 2 ounces Pure glycerine 4 ounces Distilled water to make 1 pint.

To the carmine in a 20-ounce bottle add 14 ounces of distilled water. Then gradually introduce solution of potash, shaking now and again until dissolved. Add glycerine and spirit of wine, making up to 20 ounces with distilled water, and filter.

«Blue Black.»—Ale droppings, 2 gallons; bruised galls, 1⁠/⁠2 pound; logwood extract, 1⁠/⁠4 pound; indigo extract, 2 ounces; sulphate of iron, 3 1⁠/⁠2 ounces. Heat together and strain.

«Finishers’ Ink.»—Soft water, 1 gallon; logwood extract, 1 1⁠/⁠4 ounces; green vitriol, 2 1⁠/⁠2 ounces; potassium bichromate, 1⁠/⁠2 ounce; gum arabic, 1⁠/⁠2 ounce.

Grind the gum and potassium bichromate to powder and then add all the coloring ingredients to the water and boil.

«To Restore Patent Leather Dash.»—Take raw linseed oil, 1 part; cider vinegar, 4 ounces; alcohol, 2 ounces; butter of antimony, 1 ounce; aqua ammonia, 1⁠/⁠2 ounce; spirits of camphor, 1⁠/⁠2 ounce; lavender, 1⁠/⁠2 ounce. Shake well together; apply with a soft brush.

«PRESERVATIVES FOR LEATHER.»

I.—Mutton suet 50 parts Sweet oil 50 parts Turpentine 1 part Melt together.

The application should be made on the dry leather warmed to the point where it will liquefy and absorb the fat.

II.—Equal parts of mutton fat and linseed oil, mixed with one-tenth their {453} weight of Venice turpentine, and melted together in an earthen pipkin, will produce a “dubbin” which is very efficacious in preserving leather when exposed to wet or snow, etc. The mixture should be applied when the leather is quite dry and warm.

III.—A solution of 1 ounce of solid paraffine in 1 pint light naphtha, to which 6 drops of sweet oil have been added, is put cold on the soles, until they will absorb no more. One dressing will do for the uppers. This process is claimed to vastly increase the tensile strength.

«Patent Leather Preserver.»—

Carnauba wax 1.0 part Turpentine oil 9.5 parts Aniline black, soluble in fat 0.06 parts

Melt the wax, stir in the turpentine oil and the dye and scent with a little mirbane oil or lavender oil. The paste is rubbed out on the patent leather by means of a soft rag, and when dry should be polished with a soft brush.

«REVIVERS AND REGENERATORS.»

By weight. I.—Methylic alcohol 22 1⁠/⁠2 parts Ground ruby shellac 2.250 parts Dark rosin 0.910 parts Gum rosin 0.115 parts Sandarac 0.115 parts Lampblack 0.115 parts Aniline black, spirit-soluble 0.115 parts

The gums are dissolved in spirit and next the aniline black soluble in spirit is added; the lampblack is ground with a little liquid to a paste, which is added to the whole, and filtering follows.

Kid Reviver.—

By weight. II.—Clear chloride of lime solution 3.5 parts Spirit of sal ammoniac 0.5 parts Scraped Marseilles soap 4.5 parts Water 6.0 parts

Mix chloride of lime solution and spirit of sal ammoniac and stir in the soap dissolved in water. Revive the gloves with the pulpy mass obtained, by means of a flannel rag.

«TANNING LEATHER.»

«Pickling Process.»—Eitner and Stiazny have made a systematic series of experiments with mixtures of salt and various acids for pickling skins preparatory to tanning. Experiments with hydrochloric acid, acetic and lactic acids showed that these offered no advantages over sulphuric acid for use in pickling, the pickled pelts and the leather produced from them being similar in appearance and quality. By varying the concentration of the pickle liquors, it was found that the amount of salt absorbed by the pelt from the pickle liquor was controlled by the concentration of the solution, 23 to 25 per cent of the total amount used being taken up by the pelt, and that the absorption capacity of the pelt for acid was limited.

The goods pickled with the largest amount of acid possessed a more leathery feel and after drying were fuller and stretched much better than those in which smaller amounts of acids were employed. Dried, pickled pieces, containing as much as 3 per cent of sulphuric acid, showed no deterioration or tendering of fiber. The pickled skins after chrome tanning still retained these characteristics. An analysis of the leather produced by tanning with sumac showed that no free acid was retained in the finished leather. An Australian pickled pelt was found to contain 19.2 per cent of salt and 2.8 per cent of sulphuric acid.

From a very large number of experiments the following conclusions were drawn: 1. That sulphuric acid is quite equal in efficiency to other acids for the purpose. 2. To a certain limit increasing softness is produced by increasing the quantity of acid used. 3. For naturally soft skins and when a leather not very soft is required the best results are obtained by using 22 pounds of salt, 2.2 pounds of sulphuric acid, and 25 gallons of water for 110 pounds of pelt in the drum. 4. For material which is naturally hard and when a soft leather is required, the amount of acid should be increased to 4.4 pounds, using similar amounts as those given above of pelt, salt, and water.

«French Hide Tanning Process.»—I.—The prepared pelts are submitted to a 3 to 4 hours’ immersion in a solution of rosin soap, containing 5 to 10 per cent of caustic soda. The goods are afterwards placed in a 6 to 12 per cent solution of a salt of chromium, iron, copper, or aluminum (preferably aluminum sulphate) for 3 to 4 hours.

II.—The hides are soaked in a solution of sodium carbonate of 10° Bé. for 3 to 6 hours. After washing with water they are allowed to remain for 5 hours in {454} a bath of caustic soda, the strength of which may vary from 2° to 30° Bé. From this they are transferred to a bath of hydrochloric acid (1° to 5° Bé.) in which they remain for 2 hours. Finally the hides are washed and the beam-work finished in the usual way. The tannage consists of a special bath of sodium or ammonium sulphoricinoleate (2 to 30 per cent) and sumac extract, or similar tanning material (2 to 50 per cent). The strength of this bath is gradually raised from 4° to 30° or 40° Bé.