3318. Powdered Tin

3318.      Powdered Tin. Take Cornish grain tin; melt it, and pour it into a wooden box, well rubbed on the inside with whiting or chalk ; close the cover, and continue shaking it violently until the tin is reduced to powder; then wash it in clean water, and dry it immediately.

3319. To Make Feathered Tin

3319.    To Make Feathered Tin. The object of feathering is to bring the tin into a state of minute subdivision, which permits it to be much more rapidly dissolved in acids. Procure an iron ladle having a capacity of about 12 fluid ounces, and a wooden or stoneware vessel containing 2 or 3 gallons of cold water. About 1 pound of pure bar tin, free from lead, is to be cut into pieces of about 2 inches in length, and melted in the ladle. When melted, pour the tin in a very small stream, from a height of about 3 feet, into the cold water. The ladle should be moved around in a small circle, when pouring, for if the whole of the melted tin strikes the water at one point, it will cool in lumps, and require remelting. The feathered tin is to be preserved in wooden boxes, the bottoms of which are perforated with small holes; or, what is better, kept in unglazed stoneware flower-pots. Solutions of tin containing iron or copper, or their salts, are unfit for dyeing bright reds. (See Nos. 107 (Acid Preparations of Tin), etc..)

3320. Moire Metallique, or Crystallized Tin

3320.    Moire Metallique, or Crystallized Tin. A method of ornamenting the surface of tin plate by acids. The plates are washed with an alkaline solution, then in water, heated, and sponged or sprinkled with the acid solution. The appearance varies with the degree of heat and the nature and strength of the acids employed. The plates, after the application of the acids, are plunged into water, slightly acidulated, dried, and covered with white or colored varnishes. The following are some of the acid mixtures used: nitro-muriatic acid, in different degrees of dilution ; sulphuric acid, with 5 parts of water, 1 part of sulphuric acid, 2 of muriatic acid, and 8 of water; a strong solution of nitric acid; 1 part nitric acid, 2 sulphuric, and 18 of water. A solution of potash is also used.

3321. Frosted Tin

3321.    Frosted Tin. A frosted appearance may be given to sheet tin by a wash of bichloride of tin.

3322. To Make a Tin Tree

3322.    To Make a Tin Tree. Dissolve 3 drachms muriate (chloride) of tin in 1 pint distilled water, adding 10 or 15 drops nitric acid; and suspend a small rod of clean zinc in a phial containing the above solution.

Nickel. A white, hard, malleable, magnetic metal, capable of receiving the lustre of silver. Its specific gravity, when hammered, is about 8.82. Nickel is very infusible. Muriatic and sulphuric acid act on it with difficulty unless mixed with nitric acid, but it is freely soluble in the latter. Nickel does not oxidize or tarnish at the ordinary temperature. It alloys well with copper, tin, zinc, etc. It is obtained as follows: Roast the powdered ore first by itself and then with charcoal powder, till all the arsenic is expelled, and a garlic odor ceases to be evolved; mix the residuum with 3 parts sulphur and 1 part potash; melt in a crucible with a gentle heat, cool, edulcorate with water, dissolve in sulphuric acid mixed with a little nitric acid, precipitate with carbonate of potash, wash, dry, mix the precipitate with powdered charcoal, and reduce it by heat. For chemical purposes pure nickel is best obtained by moderately heating its oxalate in a covered crucible, lined with charcoal. The salts of nickel in the anhydrous state are for the most part yellow; when hydrated, green, and furnishing pale green solutions. Nickel is found present in meteoric iron, and is strongly magnetic, but loses this property when heated to 350° Fahr. It is chiefly employed in the manufacture of German silver. Sulphate of nickel is used medicinally, with soothing and soporific effects.