HUJIAX UHLK. 



395 



Compoaition Before and After Suckling.— The average 

 composition of 37 samples taken before and 37 samples after 

 suckling was found by Carter and the author to be — 



TABLE ex. 



In one case, where the secretion was excessive, the analyses 

 before and after suckling were practically identical ; in another, 

 where a very deficient supply was given, the fat differed greatly. 



TABLE CXL 



In 15 cases the fat was higher before suckling than after 

 suckling, and in 21 it was lower, while in 1 case it was identical. 

 The cases in which the fat was higher before suckling than after 

 were generally when the mother was lying down, indicating 

 that the separation of cream was largely mechanical. 



Analysis of Human Milk.— As the quantity of the sample 

 is often very limited, the Gerber-Eitthausen method for the 

 analysis of human milk is useful ; 5 c.c. are diluted with 100 c.c. 

 of water, 3 c.c. of copper sulphate solution added, and caustic 

 soda solution drop by drop till the precipitate settles readily ; 

 the precipitate is collected in a Gooch crucible washed with 

 water, and dried in the water-oven. The fat is extracted by 

 percolating with ether, and the crucible after several percolations 

 being allowed to stand in a beaker containing ether overnight. 

 The "ether is evaporated and the fat weighed, and if very dark 



