FERTILIZER CONTROL STATION. 



339 



f • r 18 lbs. Timothy hay, 



Third Period j Cows A and C (each) ^ 3^ " corn meal, 



' I f 2i " cotton-soed meal. 



4 weeks. ' \ ^ J^ ," cotton-seed 



Feb. 28th to Mar. 27th. I p _ R ,^, ,, f 18 lbs. clover hay, 



' Cows B and D (each) J 3| " corn meal, 



^. C 2^ " cotton-seed 



meal. 



Certain points in the plan of the experiment should be noted. 



(1) The weights of food are the same throughout, the differences 

 being in the kind of material. 



(2) The rations in the 1st and 3d periods are alike, in both of 

 which an equal weight cotton-seed meal is substituted for a portion 

 of the corn meal of period 2d. 



(3) Throughout all the periods two cows received Timothy hay 

 and two clover hay, in other respects the ration being the same for 

 all the cows. 



During the last two weeks of each of the three periods, the fol- 

 lowing data were recorded : 



(1) The weights of milk from each cow, night and morning. 



(2) The percentages of cream from the night's and morning's milk 

 of each cow. 



(3) The composition of the night's and morning's milk from each 

 cow. 



(4) The weight of unsalted butter from the milk of each cow. 



Record was also made of the weights of the cows at the be- 

 ginning and end of each period, and also of the dailj' weight of any 

 unconsumed food. 



(1) Composition of the milk. The table below shows the aver- 

 age composition of the milk for the last two weeks of each period. 

 The figures represent pounds in 100. 



Tliese figures show the average composition of each cow's milk to 

 have been practical!}' the same for each period, a result somewhat 

 surprising, as there is usually an increase in the solids and fats with 

 the increasing length of time a cow is milked after calving. 



