ELISHA MITCHELL SCIENTIFIC SOCIETY. 97 



depth of precipitate produced by ferric chloride after the addition 

 of sodium acetate, with that produced in solutions of known 

 strength. The extract was determined by evaporation on a 

 water- batli followed by two and a half hours heating in the 

 steam bath. As the temperature of the steam-bath generally 

 lies between 95° and 97° the results thus obtained are high com- 

 pared with those gotten by heating at 100° or 110°. 



13 



