p. v. SPECIFIC GRAVITY OF MILK. 209 



Shorthorn. Jersey. Kurry. 



(Non- fatty solids . . 9*0 . . 9*6 . ' . 9'2 



Fat . . . . _3-5 . . _61 . . _^0 

 Total solids 12 '5 147 13 '2 



Evenim 



: Non-fatty solids . . 9 'I . . 9'6 . . 9 '3 

 Fat .... 4-4 .. 6-3 .. 5'1 

 Total solids 13'5 15'9 14'4 



The points of interest here are the enormous richness of the milk 

 of the Jerseys, and not less the high quality of that of the Kernes, 

 which latter certainly surprised many dairy farmers. 



The great uniformity of the specific gravity of milk is very note- 

 worthy. In the case of the mixed yield of a large number of cows it 

 rarely falls outside the limits of 1*080 and 1*034 (water being 1*000). 

 In view of the considerable variations in composition which obtain 

 between, for example, ShorthornX and Jersey milk, this may seem re- 

 markable, but the circumstance is readily explained by the fact that 

 the higher percentage of fat, which tends to lower the specific gravity, 

 is usually associated with an increased amount of non-fatty solids, 

 which exercise an influence in the opposite direction. Though larger 

 variations certainly do occur in the milk of individual cows, yet in the 

 1,052 samples of Shorthorn, Jersey, and Kerry milk to which reference 

 has been made, only 50 samples registered a specific gravity below 

 1*030, and only 73 samples notably of Jersey milk gave a specific- 

 gravity above 1*034. By far the greater number of these exceptional 

 specific gravities were not below 1*029, nor above 1*035 ; though the 

 lowest actually observed was 1*0240, and the highest was 1*0365. 



The quality of milk greatly depends on the quantity which the cows 

 will yield and the nature of the food, but most of all on the breed of 

 the cows. The quantity is, to a certain degree, influenced by the manner 

 in which the cows are milked ; and it behoves every dairy- man to pay 

 a little more attention to this important process than he is generally 

 accustomed to do. If a cow is roughly handled, it is not only painful 

 to her, but will also cause her to withhold a portion of her milk ; 

 whereas, if it is gently drawn, she will yield it freely. It is of im- 

 portance that it should be drawn to the last drop, for although we do not 

 pretend to believe what has often been asserted, viz. that the last half- 

 pint is richer in cream than the whole of the rest, we fully admit that 

 whatever milk is left in the udder is liable to coagulate and injure the 

 udder, as well as to lessen the subsequent " meals of milk." It some- 

 times happens that the cows are restless and fidgety ; but they should by 

 no means be harshly or severely treated at such times. If the udder 

 is hard and painful, it should be fomented with lukewarm water, and 

 gently rubbed, by which simple expedient the cow will generally be 

 brought into good temper, and readily yield her milk. It is also proper 

 to feed the cows at the time of milking, for, while eating, the} 7 give out 

 their milk with greater freedom. They are also prevented, by the 

 motion of their jaws, from the habit, which some acquire, of with- 



