DvN.kmt'rE, called by the miners of Colorado and Nevada the "giant powder," has of late years superseded the nitro-glycerine which is its principal component. Induced by the calamitous and inexplicable accidents that so often attended the use of nitro-glveerine, and which it seemed impossible to guard against, Nobel sought, by soaking various inert substances with nitro-glycerine, to obtain some composition which should have the valuable powers of the explosive oil without its deadly risks. In 1867 be gave the name of dynamite to Abe Atte,Fiaerf11/.. outcome Of experiments. as generally manufactured, consists of infusorial earth, porcelain earth, coal-dust, siliceous ashes of the like, saturated with about three times its weight of nitro-glycerine—though the pro portion varies with different makers. According to its elements, it i.i to the eye a gray ish-brown, reddish, or blackish powder, damp and greasy to the touch, and without smell. In the open air it burns quietly, and gives off fumes of carbonic acid and nitrogen with a watery vapor. If properly made, it ought not to be exploded by heat up to 212°, by a spark, or by any ordinary shock; though cases are said to have occurred where one of these causes singly has sufficed. In order to take advantage of its enor mous blasting power, it is pretty tightly packed in paper or parchment cartridges, and exploded by means of a fulminating tune or cap. It leaves a white ash, with little or so
smoke. In the hands of careful worxmen who know what they are about, its use is comparatively free of danger, and it may be easily transported. It is now regarded as one of the safest of explosives, though its manufacture is still attended with great risks. Over gunpowder it has the advantage that it is not injured by damp: it also saves labor, fewer and smaller holes sufficing in blasting operations. It costs about four times as much as gunpowder, but performs eight or ten times as much work. The violence and rapidity of its explosion renders dynamite unlit for use in tire-arms. It is reckoned that in 1875 at least 100,000 cwts. of dynamite were manufactured in Europe.
Various other nitro-glycerine powders or compounds have been patented. Dualline is said to consist of wood gunpowder soaked with the oil; or of nitro-glycerine, fine saw dust, little niter. The improved lithofracteur contains 52 parts of nitro-glycerine, 30 of silex, 12 of coal-dust, and 2 of sulphur. Colonia powder, fulminatine, lignose, sebastine, heracline, are all names for compositions in which nitro-glycerine is the chief ingredient, and are all more or less valuable as explosives.