506 PRACTICAL ORGANIC CHEMISTRY To obtain the necessary pressure on the Hd, and for general protection when the bomb is being heated, the bomb is placed in a heavy metal case G, in which the collar E of the bomb rests in a circular recess at the top of G, and the base of A just appears through the bottom of G. The lid H of the case screws down over G, and has an orifice through which the pillar F of the bomb projects when H is screwed firmly down onto G. The bottom portion of G and the sides of H are made of hexagonal cross-section so that both can be firmly held with suitable tools whilst H is being screwed down and is thus thrusting the lid C of the bomb firmly down onto the base A. : t01 JFiG. 92. Method. Clean and dry the bomb and its lid. The powdered com-pound to be analysed can now either be weighed directly into A, or weighed by difference using a weighing-cup of the type shown in Fig. 90. Weigh out thus 15-40 mg. of the material into A. Weigh out 0-4 g. of a finely powdered mixture* of equal parts of lactose and potas-
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This note was uploaded on 09/19/2011 for the course CHM 2211 taught by Professor Castalleano during the Fall '06 term at University of Florida.