Tin salt is made by the dissolution of granulated tin in hot hydro-chloric acid, the solution being evaporated to a syrupy consistency and then crystallized.
To test tin, break it, and it will give out a singular crackling sound. Various impurities in tin can be recognized in the following manner: Dissolve tin in clear regia and mix a portion of this solution with potassium ferro-cyanide. If there is a white precipitation, it is tin; if a blue precipitation, there is a trace of iron present; and if there is a red-brown precipitation, there is copper present. For the detection of lead, add to your mixture a quantity of sulphuric acid. To detect the presence of lead in tin dissolve potassium bichromate in water, then acetic acid is to be applied to the tin you wish to test. This will product a whitish coating. Next apply your potassium bichromate solution, and if the whiting coating shows traces of yellow, there is lead in the tin. The yellower the coating, the more lead.
96 parts Copper, 2 parts Zinc, 1 part Arsenic.
Tombac is a copper-zinc alloy composed of:
(1) 85 parts Copper, 15 parts Tin.
(2) 92 parts Copper, 8 parts Tin.
(3) 85 3-10 parts Copper, 14 7-10 parts Tin.
(4) 86 4-10 parts Copper, 13 6-10 parts Zinc.
(5) 87 parts Copper, 13 parts Zinc.
(6) 80 parts Copper, 17 parts Zinc, 3 parts Tin.
Tournay's metal is a copper-zinc alloy composed of:
82 54-100 parts Copper, 17 46-100 parts Zinc.
For ordinary draughtsmen's tracing paper, saturate the paper well with a mixture of one part of balsam of fir and three parts spirits of turpentine. Dry the paper by hanging it up.
(2) A temporarily transparent tracing paper may be made by dissolving castor oil in absolute alcohol, and applying the liquid to the paper with a sponge.
The alcohol evaporates and leaves the paper dry, when the tracing may be made. If the paper is then immersed in absolute alcohol the oil will be removed and the paper restored to its original opacity.
For a transfer composition for transferring figures of any kind on stove patterns: The composition is made of 1 1/2 lbs. dark glue, 1 1/2 lbs. dark resin, 3 lbs. common whiting, 3 gills boiled linseed oil. Dissolving the glue to a thick paste, dissolve the resin in the oil by heating it, mix the whole with the whiting to a heavy dough. Keep the composition in a damp place, and, when desired for use, soften with steam. To transfer ornaments, etc., the first step is to get the ornament or letter sunk in rosewood by a practical stove pattern carver, then press the composition into the die under a light book press (letter press) and a sharp raised transfer of the die is obtained. Cut this off with a knife and paste on the wood pattern with shellac. Artistic ornaments and the entire alphabet will be done to order by a first-class die sinker at a reasonable price.