70° STORRS AGRICULTURAL EXPERIMENT STATION. 
length of time given to the study of each of the sixteen herds 
visited. In this first winter’s work, which was regarded as pre- 
liminary to an investigation that might extend over a series of 
years, it was thought better to examine a relatively large number 
of herds, each during a short period, than to make the periods 
longer and the number of herds less. 
The chief points upon which information was obtained were:— 
Number of animals in the herd.—In considering the number of 
animals, only those which came into the test were included. 
Usually these were all of the cows on the farm which were in 
milk at the time of the test. 
Breed, age and approximate weight of each cow.—The breed and 
age were obtained as accurately as possible from the owner. 
Since it was not practicable to take to the farm scales large 
enough on which to weigh the cows, the weights were estimated. 
This estimation was made in each case by the Station representa- 
tive, and it is hoped that the errors of judgment may run more or 
less equally through all the herds examined. 
Number of months stnce last calf.—In most cases the time at 
which the cow dropped her last calf was known. 
Number of months till due to calve.-—There was, of course, more 
or less uncertainty in this regard. 7 
Weights of milk-flow for the five days —The milk of each cow at 
each milking was weighed as soon as milked, to the nearest tenth 
of a pound, by the Station representative. 
Percentages and amounts of butter-fat in the milk.—A sample of 
the milk of each cow, at each milking, was taken for the deter- 
mination of the quantity of butter-fat. The Babcock method of 
fat determination wasemployed. From the percentages of butter- 
fat,in the milk, and the total weights of the milk, the daily yields 
of butter-fat were obtained. 
Kinds and weights of foods used —The feeder was requested to 
~ use the same kinds and amounts of feeding stuffs during the test 
period as he had previously used. ‘The quantity for each animal 
was weighed by the Station representative just before feeding. 
Any portions of the food left uneaten by the cows were carefully 
weighed, and due allowance was made for these uneaten residues 
in estimating the amounts daily eaten. During the test, usually 
on the third day, samples of each food used were carefully taken 
and at once sent to the laboratory for analysis. From the results 

