its inevitable effect; but this slight temporary set-back is immediately followed by a secondary, and temporary, acceleration.
It is worth our while to draw a separate curve to illustrate on a larger scale Hisãs careful data for the ten months of pre-natal life (Fig. 9). We see that this curve of growth is a beautifully regular one, and is nearly symmetrical on either side of that point of inflection of which we have already spoken; it is a curve for which we might well hope to find a simple mathôÙeôÙmatôÙiôÙcal expression. The acceleration-curve shown in Fig. 9 together with the pre-natal curve of growth, is not taken directly from Hisãs recorded data, but is derived from the tangents drawn to a smoothed curve, corôÙreôÙsponôÙding as nearly as possible to the actual curve of growth: the rise to a maximal velocity about the fifth month and the subsequent gradual fall are now demonstrated even more clearly than before. In Fig. 10, which is a curve of growth of the bamboo28,