ix TESTING OF TRYPTIC ACTION 171 



To test the tryptic action of the dry powder, dissolve 

 a little of it in a small quantity of a '5 to 1 per 

 cent sterilised carbolic acid solution and add it to 

 a tube of carbol gelatine (5 to 7 grammes of gelatine 

 to 100 cc. of a 1 to 2 per cent solution of carbolic 

 acid). 



The gelatine will be liquefied. 



