The following directions for preparing fulminate of mercury are taken from Bloxam's "Chemistry, Inorganic and Organic." "Dissolve 25gr. of mercury in half a measured ounce of ordinary concentrated nitric acid (sp.gr. 1.42) in a 1/2-pt. beaker and cover with a dial-glass; the solution may be allowed to take place in the cold, or it may be accelerated by gentle heating. It contains mercuric nitrate, nitric acid, and nitrous acid. When all the mercury is dissolved, remove the beaker to a distance from any flame and pour into it, at arm's length, 5 dr. (measured) of alcohol (sp. gr. 0.87). Very brisk action begins, and the fulminate separates as a crystalline precipitate; dense white fumes, having the odours of nitrous ether and aldehyde, pour over the sides of the beaker; they contain mercury compounds and hydrocyanic acid also, and are very poisonous. When red fumes begin to appear abundantly, some water is poured in to stop the action (which occupies only two or three minutes), and the fulminate is collected on a filter, washed with water as long as the washings taste acid, and dried by exposure to air."