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EARL W. FLOSDORF 



Liquid air or nitrogen may be used for still lower temperature. Dry 

 Ice in large Thermos bottles is also simple and convenient for storage. 

 The ice cube compartment of household refrigerators is suitable for 

 storage of small quantities of product and even for freezing when the 

 amounts involved are small. For more rapid freezing than otherwise 

 would be obtained by use of the ice cube compartment, a bath of 



Fig. 2. C'lAoclniii Ivpc of equipment for desiccating from the frozen state. 

 Regenerable desiccant comprising mostly calcium sulfate (Drierite) with a small 

 amount of silica gel (for small amount of vapors other than water) contained in 

 baskets within the white tank. Manifold is shown with outlets to which indi- 

 vidual containers for drying are attached. At the end of drying, the glass tubes 

 attaching the containers to these outlets are sealed by fusion with a flame. (Cour- 

 tesy F. J. Stokes Machine Co.) 



alcohol may be chilled to a low temperature beforehand. Then by 

 immersing a glass container of the product in the alcohol a complete 

 and rapid freezing may be obtained because of the faster transfer of 

 heat to a liquid. When larger amounts of material are involved, 

 some of the currently available home freezers are suitable. The 

 only technical skill required is good judgment in the matter of rotat- 



