328 Report oF THE CHEWIST OF THE 
10. General summary. 
In studying the composition of milk in the succeeding pages, it 
will be well to keep in mind the following facts: 
(1.) The factory-milk represents the mixed morning and 
evening milk from numerous herds of cows. 
(2.) The factory-milk of May and September came from the 
same herds of cows. 
(3.) The factory-milk of the other months represents, in every 
case, a different factory and different cows from those of the other 
months. 
(4.) It is the rule in the case of the factory-cows, to commence 
the lactation period in the spring; and, hence, our factory data 
represent in reality, the changes due to advance of the period of 
lactation, modified, to some extent, by special conditions, such as 
food, weather, etc. 
(5.) About one-half of the milk used in the station experiments 
came from our station-herd, representing several different breeds, 

in every stage of lactation. The rest of the milk was obtained 
from different sources. The data obtained from the station-experi- 
ments in regard to the composition of the milk do not, therefore, 
illustrate in such marked degree as do the factory-experiments 
the changes due to advance of lactation. 
aS 
