208 



PREPARATION OF PEPTONES 



purpose of conducting the peptone solution, in drops, 

 into the flask. These drops evaporate immediately, 

 and no scum is formed. 



FIG. 9. 



The peptone solution must never be strongly 

 evaporated, until we. have repeatedly satisfied our- 

 selves, that it is actually free from sulphuric acid and 



