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THE ROYAL SOCIETY OF CANADA 



E is sealed on the still, great care being taken that the flame does 

 not enter the tube. In order to provide for the washing out of any 

 deposit that might be introduced while joining, the branch tube F is 

 attached before the final washing. Next the aspirator is started and 

 the tube heated again to insure complete removal of moisture. It 

 will be observed that the joint at E is the only one over which the 



Fig. 3. 



substance passes before condensation. After the tube is cooled the 

 narrow parts at A and B are drawn down to about • 1mm. so that the 

 final sealing off after the tube is filled is accomplished with a minimum 

 of heat. This is possible because D is connected by a flexible tube 

 to the aspirator and the still can be rotated in its support so that these 

 small tubes may be drawn down easily. With the aspirator running, 



