in weight is a function of the rate of growth in these magnitudes, though we are not yet in a position to equate the terms precisely, one with another.
If we take not merely the variability of stature or weight at a given age, but the variability of the actual successive increments in each yearly period, we see that this latter coefficient of variability tends to increase steadily, and more and more rapidly, within the limits of age for which we have information;