THE MICROSCOPE IN PHYSIOLOGY. IOI 



piocesses or agents to which certain vegetable sub- 

 stances have been subjected. Illustrations of this are 

 afforded by the starches of wheat and barley ; it can be 

 determined by the microscope whether these are raw, 

 baked or boiled, or whether malted or unmalted."* 



Cocoa adulterated with Potato Starch. 



This figure shows a sample of cocoa adulterated with 

 potato-flower ; at a you will notice the starch-granules, 

 cells, and spiral vessels of cocoa ; at b you will see 

 the large characteristic granules of potato-starch. 



Milk is a substance very frequently adulterated. 

 " If the testimony of ordinary observers, and even of 

 many scientific writers, is to be credited, there are few 



* "Adulterations Detected in Food and Medicine," pp. 44, 45. 



