GRANULA′TION

The act or proce of forming, or breaking into, grains or small ma es. The granulation of MEDICINES has of late years received considerable attention from both foreign and British pharmaceutists. In France, granulated powders ( POUDRES GRANULÉES ) are coming into general use in place of impalpable powders, the most unpleasant of all forms of medicine. The French proce consists in enveloping the particles of medicines in syrup by means of heat and constant stirring. Mr Banner, of Liverpool, has lately introduced a method of granulating medicines far preferable to that of the French pharmaceutists. The powder to be granulated is placed in a mortar, and mucilage of gum acacia is gradually added until a crumbly ma is made; this is then rubbed through a wire sieve (about 12 meshes to the inch), and the granules produced are spread out on paper, and left to dry spontaneously, or they are placed in a copper pan, and kept in constant motion over a stove until dry; when perfectly dry, they are placed in a mortar, and sufficient quantity of strong tincture of tolu (3 dr. to 1 oz.) is added to them, until by constant stirring they all appear glo y and shining; they are then dried again by a gentle heat, being kept in constant motion. The granules thus formed keep well, are tastele , and are much more elegant and agreeable preparations than pills or ordinary powders. Many saline substances are granulated by the simple proce of di olving the salt in water, and evaporating to dryne with constant stirring. Metals are granulated (reduced to drops, grains, or coarse powder) by pouring them, in the melted state, into water. In many cases they are allowed to run through the holes of a species of colander or sieve to produce minute division; and in order to render the drops spherical, they are allowed to fall from a sufficient height to permit of their acquiring the solid state before striking the water. Lead shot is made in this way. Shot towers are often upwards of 100 feet in height. See Copper , Gunpowder , Powder , Zinc , .