dynamis], or Giant Powder. The general name for various explosives, prepared by mixing nitro-glycerine with some absorbing substance which prevents leakage. The materials used for this purpose are sawdust, silicious marl, rotten-stone, tripoli, the meal of Indian corn, sponge plaster, and an infusorial earth known as "keiselguhr." Its explosive powers are very great, while it is far safer to handle than nitro-glycerine. It was discovered in 1867 by Alfred Nobel, a Swedish chemist.