CALCIUM AND PHOSPHORUS IN THE FEED OE DAIRY COWS. 17 
compared with those of other approximately similar animals used 
as controls. 
The data in the case of the animals which had been on test are 
rather complicated. In our experiments all these animals were dried 
on 7 60 days or more before they were due to calve and were fed during 
this period on a basal ration of 3 pounds grain mixture D, 5 pounds 
alfalfa hay, and 30 to 35 pounds corn silage. The controls received 
this ration fed in the usual way and without any supplement. The 
others received grain and hay on alternate days and with phosphate 
added to the grain. It would be possible to compare the experiment 
animals directly with the controls in this series, but as they are not 
exactly comparable and as the cases are few we have thought it better 
to take into account the past records of both controls and experiment 
animals. We have, therefore, compared the performance of each 
animal, after either control or phosphate feeding, with her perform- 
ance in the preceding year and determined whether the phosphate or 
control performances compare the more favorably with the preceding 
performance of the same animal. 
For several years before the experiments began the cows from the 
general herd, of which the histories are tabulated in Tables 1 and 2, 
were fed approximately according to the Savage standard. They 
received on the average about 0.25 pound protein and 1 pound total 
nutriment more daily than this standard calls for. The building of 
the calf annually is not taken account of in this calculation, but the 
yearly 91 pounds protein and 365 pounds total nutriment received 
over and above what the standard calls for should have provided 
sufficiently for this process, according to Eckles's results (3). 
The manner in which the test cows were fed contrasts strongly 
with the above method. During the year in which they were on test 
and actually milking these animals received a daily average surplus 
of 1 to 1.5 pounds protein and about 4 pounds total nutriment. For 
a number of weeks before they calved they received the enormous 
daily surplus of about 4 pounds protein and 16 pounds total nutri- 
ment. In other words, the ration fed before calving in preparation 
for the test contained about six times as much protein and about 
three times as much total nutriment as is required for maintenance. 
In the course of a year, taking into account the dry period before 
going on test, these animals received about 100 per cent more protein 
and about 50 per cent more total nutriment than is called for by the 
Savage standard. 
It will be noted that the character of the experiments has made it 
necessary to keep the animals under observation for periods of more 
than a year, and to use the milk yield as a measure of the results to 
be studied. In the course of a year innumerable small things, which 
