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scope were compared with the gravimetric method. Considerable trouble 

 was experienced in seciiriug flasks with uniform neclis for the Short 

 method, the variations in the flasks beiag su fficient to make ditierences 

 of from I to 1.45 per cent in the results of the fat determinations. The re- 

 sults indicated by the lactoscope were variable throughout, while those 

 ootained with the Short test agreed very well with the gravimetric, the 

 greatest variation being 0.23 per cent of fat. " ]!!Teither the lactoscope 

 nor the Short method are reliable in testing skim-milk." 



Churn test as compared with Short test. — The object of the experiments 

 was to test the practicability and fairness of paying for milk according 

 to its actual butter value as indicated by the Short method. Tables 

 show the percentages of butter fat found by Short's method in eighty-eight 

 lots of mixed milk, and a comparison in seventeen samples of the weights 

 of butter fat as calculated from the percentages found by Short's method 

 with the weights of salted butter obtained by churning. With three 

 exceptions the weight of butter actually obtained with the churn was 

 slightly more than that of the total butter fat indicated by the Short 

 test. On the average 101.4 pounds of butter were obtained for every 

 100 pounds of fat in the milk as indicated by the Short method. The 

 autlior concludes that Short's method is trustworthy, provided the 

 tubes necessary in its use have been properly made and graduated, and 

 that it could be used as a test in paying for milk on the basis of its 

 actual value for butter making. 



Churning tests with cream of different degrees of acidity. — These trials 

 were made for the purpose of testing the eftect of acidity developed 

 in the ripening of the cream upon the quantity and quality of butter. 

 *'For the purpose of locating the cause of the variations in the butter 

 yield the cream was examined daily during the latter days of the series 

 of trials just mentioned." It was found that although the conditions 

 of temperature and concentration of the cream remained iiractically 

 constant, the amount of acid developed during the ripening process 

 varied considerably. Where the per cent of acidity was lowest, there 

 the yield of butter from churning fell below that indicated by the 

 Short test, otherwise it was higher. Of the three cases above refer, 

 red to in which the butter yield fell below the fat, as determined by 

 Short's test, two came in the days when the acidity of the cream was 

 tested, and in both the quantity of acid was small. In a series of 

 twenty-two subsequent trials the method of procedure was as follows : 

 In all the trials the cream was thoroughly mixed, divided into two 

 equal parts by weight, and allowed to ripen slowly under like condi- 

 tions of temperature. Tests of the acidity of the cream were made 

 just before churning. While one half was churned as soon as ripened, 

 the other half was allowed to stand until it had become strongl3' acid 

 before churning. The term " per cent of acidity" is used empirically, 

 as " the lactic acid equivalent of the amount of alkali necessary to 

 bring about a neutral reaction in 50 cubic centimeters of cream." 



