10 
A NOTE ON ANTHROPOMETRY 
is of little help, A map of Bantu Africa distinguishing the 
circumcised from the uncircumcised would be like a patchwork 
quilt. In one province of life, indeed, where fashion is 
proverbially fickle, people in certain parts of the world are 
strangely unchanging. The East has seen many invasions, 
social revolutions, new religions, since she last changed her 
clothes. And one of the indications of the profundity of 
Western influence over the East is that her sons now put on 
trousers and boots. 
But if man can thus change his language, religion, customs, 
he cannot add a cubit to his stature. The one thing that 
does not change in the members of a race is the shape of the 
bony framework of their bodies. The shape of the cranium 
and the nasal bone, for instance, are believed to persist un- 
changed in spite of changes in diet or with emigration to new 
latitudes and elevations. 
The application may be described as follows : If one 
measures a man’s head in two dimensions, lengthwise and 
breadthwise, and divides the breadth by the length, one gets 
his ‘ cranial index.’ The head, for instance, may be eight inches 
long and six inches wide. The cranial index in that case, 
omitting the decimal point, is 75. If one takes a thousand 
typical Englishmen and measures their heads one finds that 
their cranial indices vary between, roughly, 72 and 88. More 
perhaps will be found to have the index 79 than any other, 
and the indices found next most commonly will be 78 and 80, 
while instances of men with larger or smaller cranial indices 
will grow scarcer the farther they get from the average index. 
One may write down the data graphically, in the form of a 
curve. The top of the curve will correspond to the index 80, 
as more have that index than any other, and at the bottom on 
one side will be represented, perhaps one man with the index 
72, and at the other perhaps two men out of the thousand with 
the index 89. 
A second curve taken in the same way from measurements 
of a second thousand typical Englishmen will coincide with 
the first. But a curve drawn on the same plan for Armenians 
or Chinamen will be very different. In these races the longest- 
headed may have an index of 80 and the broadest one of 95. 
