274 Original Articles. [ April, 
water, the admixture is indicated at once by the specific gravity of 
about 1:025. 
6. That for these reasons the hydrometer or “lactometer” which 
gives the specific gravity of milk is well adapted for detecting the 
admixture of water, or to show an unusually poor quality of the un- 
adulterated milk. 
1. Circumstances affecting the Quality and Quantity of the Milk.— 
The period of the milking at which the sample is taken. During 
the process of milking, that which is first drawn off is thin and 
poor, and gives little cream: improving during the flow—the last 
drawn—the “strippings’’—is the richest in quality, yielding better 
cream, and consequently more butter. 
Experiments by Reisct and Pelligot have established the fact that 
considerably more solid matter and pure fat are contained in the milk 
last drawn from the udder. 
This superior richness of the last-drawn milk has an important 
bearing upon the question of milking machines. The new American 
cow-milking machine fails to strip the udder, according to the united 
testimony of all who have tried it. Such a fundamental defect must 
militate against its general introduction into England, and has led to 
its disuse in the United States, as I am informed by the secretary of 
one of the most influential State Agricultural Societies, 
It has, to my own knowledge, been tried by several .excellent 
judges, who remain silent as to its merits, not liking to accept the 
unpleasant office of condemning and declining, as judicious men, to 
bestow undeserved praise. 
2. Distance from the time of Calving.—The first milk, or colostrum, 
is thicker and yellower than ordinary milk, coagulates by heating, and 
contains an unusually large quantity of casein or curd. 
Tn ten or twelve days from the time of calving, the milk assumes 
its ordinary condition, and the flow then becomes very plentiful ; but 
after a month, or thereabouts, the yield gradually diminishes until 
the animal runs dry, usually in about ten months, unless when suc- 
culent and stimulating food is given to excite the continuance of the 
secretion for a longer time. 
3. Season of the Year and Food.—In the spring and early part of 
summer milk is abundant, and of good flavour. As the season 
advances the supply is diminished, but becomes richer in butter. 
The same quantity of milk which in August scarcely yielded 3 per 
cent. of pure butter and 5 per cent. of curd, in November produced 
41 per cent. of butter and 33 per cent. of curd. 
A series of observations, made for the purpose of ascertaining the 
variations in the quality of the milk on the same farm throughout the 
year, convinced me that the supply of food was chiefly concerned, the 
richness or poverty of the diet being in all cases represented by the 
quality of the milk yielded. 
In November and December the cows had meal-nut oil given to 
them, which is the refuse left after pressing ground kernels of the 
palm-nut. This substance, when of good quality, not too hardly 
