Densimeter

An apparatus for obtaining the specific gravity of gunpowder by immersing it in mercury. It consists of an open ve el containing mercury, a frame supporting a gla globe communicating by a tube with the mercury in the open ve el, and joined at top to a graduated gla tube, which communicates by a flexible tube with an ordinary air-pump. Stop-cocks are inserted in the tubes above and below the gla globe, and a diaphragm of chamois-skin is placed over the bottom orifice and one of wire cloth over the top orifice of the globe. The arrangement allows the globe to be filled with mercury to any mark on the graduated tube, or with gunpowder and mercury. The globe can be taken off and weighed in both cases. The specific gravity is obtained from the relation between the weights in the two cases.