New YorK AGRICULTURAL EXPERIMENT STATION. 219 
culent white precipitate, settling to the bottom of the vessel, 
leaving a supernatant liquid of a bright yellow color. The 
separation of the precipitate may be hastened by vigorous stir- 
ring. The precipitate is filtered, washed with water and then 
dissolved in 1 or 2 liters of 1 per ct. solution of sodium carbon- 
ate. The resulting solution appears to be complete, though it 
is milky in appearance. It is filtered, reprecipitated by dilute 
hydrochloric acid and the precipitate filtered and washed. This 
process of redissolving and reprecipitating is repeated three or 
four times in all. From this point, two different methods may 
be employed for further purification of the substance. By one 
method, the third or fourth precipitate by hydrochloric acid is 
thoroughly washed with water containing dilute hydrochloric 
acid, then with alcohol, and finally with ether, after which it 
is extracted by boiling ether for several days, until all traces 
of fat are removed. It is then dried to constant weight at 105° 
to 110° C. for analysis. By the other method, the third or fourth 
solution in dilute sodium corbonate is made exactly neutral by 
hydrochloric acid, treated with 3 per ct. of chloroform to pre- 
vent any bacterial action and dialyzed in running water until 
all chloride is removed. The resulting solution is concentrated 
on the water-bath to a thick syrup and while still warm is 
poured into a mixture of 95 per ct. and absolute alcohol. This 
is allowed to stand 2 or 3 days. A white gelatinous coagulum 
results, which is filtered, washed thoroughly with alcohol, 
placed under absolute alcohol several days, again filtered, 
treated with cold ether, then dried, powdered and extracted 
with boiling ether until all fat is removed. It is then finally 
dried to constant weight at 105° to 110° C. This method of 
dialvzing, concentrating and then precipitating by alcohol in 
neutral or alkaline solution appears usually to carry down with 
the precipitate large quantities of ash. Jackson? has pointed 
out this fact and has shown that this may be avoided by using 
the first method given above or by Pcie Le with alcohol 
in the presence of dilute acid. 
We present in the table below the results of analyses of sam- 
ples of the substance prepared from different cheeses. The 
°Am. Jour. Physiol., 43 170 (1900), 
