322 MILK AND MILK PKODUCTS. XIV. 



(4'30%) in November, at its minimum (3 '79%) in June; the 

 solids not fat showed a maximum (8*92 %) in October and a 

 minimum (8-71%) in August. 



Influence of time and manner of milking. In most cases 

 cows are milked twice a day morning and evening. The 

 intervals between the two milkings are usually unequal, being 

 often 10 or 11 hours and 14 or 13 hours respectively. It is 

 almost invariably found that the proportion of fat is distinctly 

 greater in evening's than in morning's milk, and in some cases 

 the difference is very great. 



In the spring of 1900 the author made a large number of 

 analyses of the separate milk of 17 cows kept at the Experi- 

 mental Farm of the East and West Hidings of Yorkshire 

 County Councils,* which showed that the proportion of fat in 

 milk is subject to much greater variation and that the diffe- 

 rences in the amount of fat in morning and evening milk, 

 especially of cows yielding large quantities, are often greater 

 than is usually stated. 



The details are set out in diagrams, five of which are re- 

 produced in Table I. The proportion of fat, it will be seen, in 

 the milk of a cow, varies enormously from day to day; e.g., 

 consider the case of cow No. 1 : On March 27th in the morn- 

 ing her milk contained l'9%fat, next morning she gave milk 

 containing 2'7%, while on the evening of April 7th 5-1% fat 

 was found. Table II. shows the maxima and minima for all 

 the cows during the whole period. The invariably higher 

 quality of the evening milk (the black line in Table I.) is also 

 clearly shown. That full value may be obtained from a study 

 of these diagrams it will be useful to give particulars of the 

 cows whose milk was investigated : 



Transactions of the Highland and Agricultural Society 1901, p. 218. 



