188 



H. S 



. H. WARDLAW. 









Percentage of total solids 



8-3 



9-6 



10-9 



24 



12-2 



13-5 



14-8 



15-1 



and over 



Number of results 



3 



12 



45 



15 



3 



2 



It will be seen from these figures that samples of milk 

 having percentages of total solids between 10*9 and 14*8 

 are of considerably more frequent occurrence than samples 

 having a percentage outside of this range. The mean of 

 this range, 12*8% may therefore be considered as the most 

 probable percentage of solids for the series. The results 

 are even more closely grouped about this value than in the 

 previous case, over 80% of the results occurring within an 

 equal range. These figures also indicate that the occur- 

 rence of percentages of total solids above this value is 

 rather less likely than the occurrence of percentages below 

 it, as the numbers of results are not quite symmetrically 

 arranged about the most probable value but lower values 

 are more plentiful than higher values. 



(5) Solids not fat — The following are the relative fre- 

 quencies of occurrence of the various percentages of solids 

 not fat observed in the samples of human milk examined. 



Percentage of solids not fat 

 Number of results 



6-3 



7-2 



8-1 



9-0 



9-9 



10-8 



3 



6 



17 



55 



16 



2 



11-7 



These figures show that samples having percentages of 

 solids not fat between 8*1 and 10*8 are much more fre- 

 quent than those having any percentage outside this 

 range. Nearly 90% of the total number of results occur 

 between these limits. The mean of this range of values, 

 9*4%, may therefore be considered as the most probable 

 value of the percentage of solids not fat of these samples 

 of human milk. It will be noticed that the numbers of 

 results are much more closely grouped about the most 

 probable value in this than in any of the other cases studied. 

 This is another way of expressing the generally recognised 



