148 Testing Milk and Its Products. 



b. As to quantity of milk produced. The milk may 

 be weighed for four days in the middle of the month, 

 and the entire month's yield obtained with considerable 

 accuracy (barring sickness and drying off), 

 by multiplying the sum by 7, iy 2 or 7%, 

 according to the number of days in the dif- 

 ferent months. The weighing is most read- 

 ily done by means of a spring balance, the 

 hand of which is set back so that the empty 

 pail brings it to zero (fig. 50). If several 

 pails are to be used, they should first be 

 made to weigh the same by putting a little 

 solder on the lighter pails. Milk scales 

 which weigh and automatically register the 

 yield of milk from twenty cows have been 

 placed on the market, but so far as known 

 FlG ' S caie Mllk have not proved satisfactory. 1 



168. Sampling milk of single cows. In sampling 

 the milk, of single cows, all the milk obtained at the 

 milking must be carefully mixed, by pouring it from 

 one vessel to another a few times, or stirring it thor- 

 oughly by means of a dipper moved up and down, as 

 well as horizontally, in the pail or can in which it is 

 held; a sample for testing purposes is then taken at 

 once. A correct sample of a cow's milk cannot be ob- 

 tained by milking directly into a small bottle from one 



1 The various state experiment stations now conduct official /r.v/.v of 

 dairy cows for breeders and dairy fiirmors, by which the production of 

 milk and butter fat by cows is determined accurately by representa- 

 tives of the stations. Information concerning these tests may be had 

 by writing to the director of the nearest experiment station. 



