Fig. 144—(1) Sitting stature. (2) Standing stature.
(Method of taking measurements with the Anthropometer.)
Index of Stature.—We know that these two measures are extremely important for ascertaining the type of stature, i.e., macroscelia and brachyscelia, determined by the proportion between the sitting stature and the total stature reduced to a scale of 100, that is, the relation of the bust to the total height of the individual. Let us remember in this connection that the bust should be a 52d or 53d part of the total stature and that below 52 down to 50, it is macroscelous, and that above 53, up to 55, it is brachyscelous.
Having obtained the two numbers corresponding to the two statures, e.g., stature 1.60 m., bust 0.85 m., how are we to find out the percentual relation between the two measurements? First, we form an equation: 85:160 = x:100.
from which we obtain x = (100×85)/160 = 53
This stature is of the normal average type, that is, it is mesatiscelous; but the mesatiscelia is high (in comparison with the other measurement that is also mesatiscelous, namely, 52), in other words, it is brachy-mesatiscelous.
Note the formula which gives us the value of x. If we substitute general symbols in place of the concrete values, we may say that x is equal to one hundred times the lesser measurement (m) divided by the greater measurement (M). If, in place of x, we substitute I, signifying index, we may draw up the following general formula of indices:
I = (100×m)/M
This formula of relations between measurements is of wide application in anthropology and is fundamental. Indices of every measurement are sought for. The one given above is the index of stature, and it determines the type of stature. All the other indices are calculated by similar procedure.
