Testing Milk on the Farm. 



139 



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 multiply- 

 ing the sum by 7, 7J or 7f , according to the number of 

 days- in the different months. The weighing is most 

 readily done by means of a spring balance, 

 the hand of which is set back so that the 

 empty pail brings it to zero (Fig. 49. ) 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 reg- 

 ister the yield of milk from twenty cows 

 have been placed on the market, but no 

 perfectly satisfactory devise of this kind 

 has yet been brought out, so far as is known 

 to the authors. 



164. 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 thoroughly by means of a dipper moved up 

 and down, as well as horizontally, in the pail or can in 

 which it is held; the sample for testing purposes is then 

 taken at once. A correct sample of a cow's milk cannot 

 be obtained by milking directly into a small bottle from 

 one teat, or by filling the bottle with a little milk from 

 each teat, or by taking some of the first, middle and last 

 milk drawn from the udder. Such samples cannot pos- 

 sibly represent the quality of the milk of one entire rnilk- 



FiG.49. Milk scale. 



