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Operations of Analysis.

Granulation is employed for the mechanicaldivision of some metals. It is performed eitherby stirring the melted metal with an iron rod,until it cools, or by pouring it into water, andstirring it continually, or by pouring it into acovered box, previously well rubbed with chalk,and agitating it until the metal cools, whenthe rolling motion will be converted into arattling one. The adherent chalk is to bewashed away; or, the melted metal may bepoured through a perforated iron ladle.

Fusion is the conversion of a solid into a li-quid, by the application of heat. The sub-stance thus rendered fluid, is said to be fused ormelted. A minute quantity of a substance maybe fused by the flame of a candle or lamp, urgedby the How-pipe. The best blow-pipe is aconical tube, furnished with a small pipe nearthe base, to which jets or caps of different perfo-rations may be adapted at pleasure. The air iseither forced into the blow-pipe by the lungs ofthe operator, or by means of double bellows at-tached to the instrument. The substance to befused must be placed upon a piece of excavatedcliarcoal, or held in a spoon, made of gold, orplatina. The quantity of the substance exa-mined by the blow-pipe should not exceed the