4 8 



Anthropological Investigations. 



males and females, and from 7 years on, in the colored individuals,, 

 the arm expanse begins to surpass the body height, and the increase 

 advances slightly with every year of life. This advance is more 

 marked in the negroes. 



A part of the increase of the arm expanse is not due to a greater 

 growth of the arms themselves, but to the lateral growth of the 

 thorax. This growth of the chest does not fully account for the 

 differences in the arm-spread between the white and the negro 

 children, and the arms of the colored individuals must be considered 

 as really slightly longer than are those of the whites. I subjoin 

 here a table which will illustrate the gradual increase of the pro- 

 portion of the arm expanse to the total height in the different 

 classes of children. 



Per Cent. Relation of Average Arm Expanse to the Average Height, 

 according to the ages of the Children. 



Measurements of the Chest. 



After experimenting with various chest measurements it was 

 found that the best satisfaction is obtained by restricting the meas- 

 urements to diameters and taking these in all the children at the 

 height of the nipples. The instrument with which the measurements 

 were taken was a pair of accurate aluminum sliding compasses, with 

 branches with broad surfaces. In measuring, the branches of the 

 compass were applied not simply to touch the skin but until they 

 met with a marked resistance on the body. Care was taken that the 



