340 QUARTERLY JOURNAL. 



butter. No. 2, was evidently richer to the eye, but the cream wat 

 pale-colored, and, when churned, yielded 181 grains of firm but- 

 ter. No. 3, the cream, before churning, had a rich yellow tint j 

 the butter produced was well flavored, and weighed 551 grains. 

 The difference between the richness of the first milk and the after- 

 ings, in a cow yielding about fifteen pints of milk at each milk 

 ing, is thus as 1 : 110. 



When a cow has calved less recently, the difference betweei 

 the first milk and afterings, however, appears not so great. O 

 the 9th of Aug-ust, the milk of the same cow, which then yielde 

 fourteen and a half pints at a milking, was subjected to expert 

 ment in a similar manner. 



The three portions were placed in similar basins in the milk-' 

 house for forty hours, and were then scalded till the temperature 

 of the milk rose to 145^^. The milk was drawn off next day from 

 below the cream by means of a siphon, and the three portions 

 were churned, in glass vessels, at the same time, for thirty minutes. 

 The butter was soft and very white, although it was allowed to 

 remain for twenty-four hours after churning in cold water. This 

 probably arose from the heat of the weather ; the thermometer 

 in the shade then standing as high as 73°. When the butter was 

 •washed, and worked to free it from water, 



No. 1 yielded 31 grains. 

 No. 2 " 252 " 

 No. 3 " 416 " 



Here the proportion between the first and last milking is as 

 1 : 13.42 nearly, or 1 : 13|. 



On this occasion, we took the opportunity of repeating an ex- 

 periment formerly made on the proportion of caseine or curd in 

 each of those portions of milk, by coagulating small but equal 

 parts of each by means of rennet, and also by sulphuric acid, 

 which we had found to afford a larger and more firm curd than 

 rennet. Two ounces of each poition of the milk, after the cream 

 was removed, were measured out, (that is, one-eighth of an Eng- 

 lish pint ;) a teaspoonful of filtered rennet was added to each ; to 

 equal quantities of the same milk forty drops of sulphuric acid 

 were added ; and the six cups were placed in boiling water for 

 some minutes. They were all firmly coagulated. The curd was 

 separated from each ; and, when equally dried, in a heat about 

 that of boiling water, each was accurately weighed. 



With Rennet. With Sulphuric Acid. 



No. 1 gave of dry curd 14 grains. ... 18 grains. 



No. 2 " " 13 " ... 18 " 



No. 3 u u 14 " ... 19 " 



3 

 1 



This shews that, though the quantity of oily matter differs ma- 



I 



