8 



An examination of the accompanying cut shows the whole appar- 

 atus — lamp, cup, condenser and receiver — to be supported, when in use, 

 by the upright K, which screws into a plate on the top of the base H. 

 Once the sample is weighed and the heat applied the work goes on 

 almost or quite automatically ; and as there is no delicate glassware 

 that requires close attention and no danger of the escape and loss of any 

 of the moisture, the operator is at liberty, during the short time that it 

 takes to evaporate the moisture, to attend to other small duties, if cir- 

 cumstances call for it, as they frequently .do. 



The reagent used serves several purposes. It prevents foaming and 

 keeps the sample from adhering to the bottom of the cup or charring 

 unduly ; a portion of it passes over with the moisture and aids in carry- 

 ing it both out of the condenser and down the receiver; while the high 

 boiling point of the reagent causes a portion of it to remain behind in 

 the cup, pass over later and thoroughly wash all the moisture out of 

 the small tube of the condenser. This last is very much facilitated by 

 the upright position of the condenser. 



Description of the Apparatus. 



A. Evaporating cup (metal). 



ai. Evaporating cup proper. 

 a2. Lid of cup. 



B. Condenser. 



bi. Jacket of condenser for holding water. 



b2. Block tin condenser tube through which the vapors pass 



to be condensed. 

 b3. Spring clamp for holding the graduated receiver, C. 



C. Graduated glass receiver. The condensed liquids flow into this, 



the water settling to the bottom of the graduated tubular neck. 

 The receiver has two scales, one for reading per cent, for 5 

 grams and the other for reading for 10 grams. 



D. Balance for weighing the sample. The cup, A, is placed in one 



pan and is readily balanced by means of the counterpoise on the 

 opposite beam. The weight is then placed in the other pan for 

 weighing the sample to be tested. 



E. Spirit lamp (metal for evaporating the moisture from the sample. 



F. Reagent outfit. 



fi. Bottle of reagent prepared for use. 

 {2. Bottle for receiving used reagent. 

 fvj. Graduate for measuring reagent. 



G. Alcohol bottle for holding wood alcohol to be used in the spirit 

 lamp. 



H. Stand or base for apparatus. 



K. Upright which screws into the base H. 



