427 



was added at different times rye, liay, straw, distillery swill, silage froDi 

 grass and serradella, commou salt, and phosphate of lime. The cows 

 were milked at 4 o'clock in the morning and at between 4:30 and 5:30 

 at night. The milk of each cow at each milking was weighed and 

 sampled. The specific gravity and the percentage of fat were deter- 

 mined in each sample, the latter in duplicate by means of a De Laval 

 lactocrite. The instruments used were carefully verified before use. 

 The weighing and sampling of the milk were all done under the direct 

 supervision of the laboratory assistant. From the yield, specific grav- 

 ity, and percentage of fat calculations were made of the total fat in the 

 milking, the percentage of solids (by means of Fleischmanu's formula*), 

 and the specific gravity of the solids; and fi'om these data the per cent 

 of solids-uot-fat and the percentage of fat in the total solids were 

 obtained for the milk of each cow at each milking. While the cows 

 were at pasture they were only Aveighed once; during the remainder of 

 the time they were weighed once a week, the weighings being made in 

 the morning after milking, 12-15 hours after the last feeding and 16-19 

 hours after the last watering. Larger variations in the weights of the 

 animals from week to week were noticed when the animals were tresh in 

 milk than when they were well advanced in the milking period. Careful 

 n.easurements and observations were made on each cow with special 

 reference to the external physical qualities supposed to furnish indica- 

 tions of the nulking capacity of the cow. 



For the milk of each day the specifi;^ gravity was calculated from 

 t'uit of the separate milkings, with due regard to the quantity of milk at 

 each milking. The percentage of fat for the day was obtained by divid- 

 ingthe total amount of fat yielded in the two milkings by the total milk 

 yield for the day and multiplying the quotient by 100. From the specific 

 gravity and percentage of fat the percentage of solids andother data were 

 calculated by the formula given above. For each month the specific 

 gravity and percentage of fat, and from these the other data were cal- 

 culated in the same way as for the day's milk. The fat Avas calculated 

 to butter containing 83.33 per cent of fat by means of the formula 



a; = amount of fat x , or amount of fat x 1.2. 



oo.oo 



This does not give the actual amount of butter which would be yielded 

 if the cream was churned; to obtain the actual amount the results given 

 by this formula must be decreased about 6 per cent. 



The monthly averages for each cow, including percentages of fat, 

 solids-not-fat, total solids, and fat in total solids, the specific gravity, 

 and the daily yield of milk are graphically shoA\Ti by means of irregu- 

 lar lines. These lines show that in the case of the cows under trial 



^ f = (1.2 X f)+ (^2.665 lOOs— 100 \ ^-^^^^ /=total solids, /^percentage of fat, 

 and 8=siiecifie gravity. Kircliner's Milchwirtschaft, 2 ed., p. 134. 



