VARIATIONS OF HUMAN MILK. 



319 



Variation with Lactation. There exist several series of analyses 

 in which the time which has elapsed since parturition has been 

 noted. Of these, the results of Carter and the author represent 

 normal milks, those which disagreed with the child in any way 

 having been excluded. The Tables due to Pfeiffer, Leeds, and 

 Camerer and Soldner contain all the analyses made by them 

 without any eliminations (Table LXXYII.). 



Meigs and Marsh state that the amount of unknown substance 

 in human milk falls off as lactation proceeds. 



Probable Mean Composition. From the above results the 

 following probable composition may be deduced for normal 

 human milk after lactation has become regular : 



Water, 

 Fat, . 

 Sugar, 

 Protein, 

 Ash, 



88-5 per cent. 



3.O 

 ' 



6-8 

 1-3 

 0-2 



Variation of Constituents. The following maxima and minima 

 have been found : 



Fat, . 

 Sugar, 

 Protein, 

 Ash, . 



9-05 (Pfeiffer), 0-47 (C. and R.). 



8-89 (C. and R.), 4-22 (Pfeiffer). 



5-56 (Pfeiffer), 0-85 (Leeds). 



0-50 (C. and R.), 0-09 (Pfeiffer). 



Composition 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 LXXVIII. 



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. 



