QUANTITATIVE METHODS OF ANALYSIS 



153 



it to the Gooch by shaking it up in the water and pouring 

 it quickly into the crucible while under suction. The 

 excess of fine asbestos should be poured off before adding 

 to crucible. 



6. Dry the Gooch with its contents in the oven, and 

 finally heat to dull redness for fifteen minutes, during which 

 the red cuprous oxid is converted into the black cupric 

 oxid. Considerable care must be taken to avoid cracking 

 the crucible, the heat being increased cautiously, and the 

 operation conducted preferably in a muffle furnace. 



7. After oxidation as above, the crucible is transferred to 

 a desiccator, cooled, and quickly weighed. 



8. From the milligrams of cupric oxid calculate the 

 milligrams of dextrose according to the following table: 



Leech, Food Inspection and Analysis, New York, p. 595, 1913. 

 Dej "ren's Table for Dextrose, Maltose, and Lactose 



