195 



The powdered cartlieuwure is not ie<[uiicd to be extracted Avitli ether 

 l»ievious to ii>se, and can l)e used over and over again by igniting after 

 use, as the milk ash remaining behind tends to improve it as au 

 absorbent. 



(4) Supplementary to these observations the author made a series of 

 tests in wliich the milk was dried on kaolin. For this purpose very 

 tine particles of kaolin, separated by means of water, Mere formed into 

 ])lates, which were baked and afterwards ground to pieces 0.5 to 1 mm. 

 in diameter. Twenty-tive grams of this was used with 10 grams of milk, 

 and the operation carried on as with earthenware. The results with 

 w hole nulk and with skim milk agreed very closely with those obtained 

 by the Adams method. This method is believed to be in every way 

 equal to the Adams, and to present certain advantages over those where 

 other absorbents are used. 



As a result of his investigations the author is led to the following 

 conclusions: 



(1) The lactocrite, when a ndxture of hydrochloric and lactic acids is 

 used, gives results reliable and coni])arable with those by the best gravi- 

 metric methods, whether the milk be rich or poor in fat. 



(2) Kaolin prepared as described gives results in close agreement 

 with those by the Adams method. 



(3) The Adams method gives thoroughly reliable results, provided 

 the strips (jf paper are thoroughly extracted with ether before using. 



(4:) The Soxhlet aerometric method is less reliable than either the 

 Adams or kaolin methods or the lactocrite ; with milks containing less 

 than 2,5 per cent of fat it is unreliable, and with milk rich in fat it 

 gives sometimes too high and sometimes too low results. 



The curdling of milk during thunderstorms, Tolemei {Ahs. 



Milch Ztg., ;J0 {1891), i). 519). — The author su^bjected fresh milk to cur- 

 rents of electricity of different intensities, and under varying circum- 

 stances, but in no instance did the souring of the milk seem to be hastened. 

 On the contrary the souring seemed rather to be retarded, for while 

 milk wliich was not treated with electricity was sour in 3 days, themdk 

 treated remained sweet for fi-om 6 to 9 days. 



After showing in this manner that the electricity is not the direct 

 cause of the souring, experiments were made on the effect of ozone on 

 milk, in which ozone prepared by the Holtz electric machine was slowly 

 conducted through milk. The milk so treated was found to curdle after 

 a few hours. He concluded that the curdling of milk is therefore not 

 attributable directly to the electricity, but rather to the action of the 

 ozone which is formed by the lightning. 



The influence of milk preservatives, A. W. Stokes {Analy,sf, IG 

 {lS91),pp. 122-1:2(>).—T]w author has made a study of the acidity of 

 milk in from 400 to 500 samples. In these investigations the acidity 

 was determined by means of decinormal soda solution, using phenol- 

 phthalein as an indicator. His observations led him to believe that 



