The curve already drawn (Fig. 35) illustrates, as we have seen, the relation of length to time, i.e. _L_/_T_ = _V_. The second (Fig. 36) represents the rate of change of velocity; it sets _V_ against _T_; _The foregoing table, extended by graphic interpolation._ Total Daily Days increment increment Logs of do. 1 — — — 2 — — — 3 1·40 ·60 1·78 4 2·00 ·52 1·72 5 2·52 ·45 1·65 6 2·97 ·43 1·63 7 3·40 ·32 1·51 8 3·72 ·30 1·48 9 4·02 ·28 1·45 10 4·30 ·22 1·34 11 4·52 ·21 1·32 12 4·73 ·19 1·28 13 4·92 ·18 1·26 14 5·10 ·17 1·23 15 5·27 ·13 1·11 16 5·40 ·14 1·15 17 5·54 ·13 1·11 18 5·67 ·11 1·04 19 5·78 ·10 1·00 20 5·88 ·10 1·00 21 5·98 ·09 ·95 22 6·07 ·07 ·85 23 6·14 ·07 ·84 24 6·21 ·08 ·90 25 6·29 ·06 ·78 26 6·35 ·06 ·78 27 6·41 ·05 ·70 28 6·46 ·04 ·60 29 6·50 ·03 ·48 30 6·53 {142} and _V_/_T_ or _L_/_T_^2, represents (as we have learned) the _acceleration_ of growth, this being simply the “differential coefficient,” the first derivative of the former curve. [Illustration: Fig. 37. Logarithms of values shewn in Fig. 36.] Now, plotting this acceleration curve from the date of the first measurement made three days after the amputation of the tail (Fig. 36), we see that it has no point of inflection, but falls steadily, only more and more slowly, till at last it comes down nearly to the base-line. The velocities of growth are continually diminishing. As regards the missing portion at the beginning of the curve, we cannot be sure whether it bent round and came down to zero, or whether, as in our ordinary acceleration curves of growth from birth onwards, it started from a maximum. The former is, in this case, obviously the more probable, but we cannot be sure.