Fulminating Plat′inum. Syn. Platinum fulminans, L. Prep. By acting on binoxide of platinum with pure ammonia. It is analogous to the gold and silver ammonio-compound.
Fulminating Powder. Syn. Detonating powder; Pulvis fulminans, L. Prep. 1. Nitre, 3 parts; carbonate of potash (dry), 2 parts; flowers of sulphur, 1 part; reduce them separately to fine powder, before mixing them. A little of this compound (20 to 30 gr.), slowly heated on a shovel over the fire, first fuses and becomes brown, and then explodes with a deafening report.
2. Sulphur, 1 part; chlorate of potassa, 3 parts. When triturated, with strong pressure, in a marble or wedgwood-ware mortar, it produces a series of loud reports. It also fulminates by percussion.
3. Chlorate of potassa, 6 parts; pure lampblack, 4 parts; sulphur, 1 part. A little placed on an anvil detonates with a loud report, when struck with a hammer. No. 1 is the substance commonly known as ‘FULMINATING POWDER,’ See Blasting Powder.
Fulminating Sil′ver. Syn. Argentum fulminans, L. Two very distinct compounds are known by this name, the one containing oxide of silver and ammonia, and the other being a true fulminate of silver.
Prep. 1. (Ammonia-compound of silver, Berthollet’s fulminating silver.)—a. Digest oxide of silver (recently precipitated and dried by pressure between bibulous paper) in concentrated liquor of ammonia, for 12 or 15 hours, pour off the liquid, and cautiously dry the black powder in the air, in divided portions. The decanted ammoniacal liquor, when gently heated, yields, on cooling, small crystals, which possess a still more formidable power of detonation than the black powder, and will scarcely bear touching, even whilst under the liquid.
b. Dissolve chloride of silver in strong liquor of ammonia, cautiously add pure potassa (in fragments), and when effervescence ceases, decant the fluid portion, and wash and dry the powder, as before.
2. (Fulminate of silver, Brugnatelli’s fulminating silver; Argenti fulminas, L.)—a. Pour alcohol, 1 oz., on nitrate of silver (in fine powder), 100 gr., previously placed in a capacious flask or beaker glass, and shortly afterwards add strong nitric acid, 1 oz.; as soon as all the powdered nitrate assumes the form of white clouds, add cold distilled water, q. s. to suspend the ebullition, and next collect the powder on a filter, and otherwise proceed as with the ammonia-compound (above).
b. (Fownes.) Metallic silver, 40 to 50 gr.; nitric acid (sp. gr. 1·37), 3⁄4 fl. oz.; dissolve by the aid of a gentle heat, add, whilst the solution is still hot, alcohol, 2 fl. oz., and again apply heat until reaction commences; the fulminate slowly separates from the hot liquid under the form of small, brilliant, white, crystalline plates, which, after being slightly washed with a little cold distilled water, are to be distributed upon separate pieces of filtering paper, in portions not exceeding 1 or 2 gr. each, and left to dry in the air. When dry, the papers are to be folded up, and carefully preserved in a box or bottle. A sixpence and the strongest commercial nitric acid and rectified spirit answer for the above purpose.
c. (Liebig.) Grain silver, 1 part; nitric acid (sp. gr. 1·36 to 1·38), 10 parts; dissolve at a gentle heat, and add the solution to alcohol of 85%, 23 parts; apply a gentle heat till the liquid begins to boil, then remove it from the fire and set it aside to cool; the fulminate of silver is deposited in lustrous, snow-white, acicular crystals, and when washed and dried, equals in weight that of the silver employed.