[351] Archiv f. Psychiatrie, vii. 652; ix. 129.
[352] Sensation et Mouvement, 57-8.
[353] R. Accad. dei Lincei (1881-2). I follow the report in Hofmann Schwalbe's Jahresbericht, x. ii. 93.
[354] Cf. Féré, Sensation et Mouvement, chap. xiv.
[355] The figures given are from an hysterical subject, and the differences are greater than normal. M. Féré considers that the unstable nervous system of the hysteric ('ces grenouilles de la psychologie') shows the law on a quantitatively exaggerated scale, without altering the qualitative relations. The effects remind us a little of the influence of sensations upon minimal sensations of other orders discovered by Urbantschitsch, and reported on [page 29] of this volume.
[356] Mitchell in (Philadelphia) Medical News (Feb. 13 and 20, 1886); Lombard in American Journal of Psychology (Oct. 1887).
[357] Prof. H. P. Bowditch has made the interesting discovery that if the reinforcing movement be as much as 0.4 of a second late, the reinforcement fails to occur, and is transformed into a positive inhibition of the knee-jerk for retardations of between 0.4' and 1.7'. The knee-jerk fails to be modified at all by voluntary movements made later than 1.7' after the patellar ligament is tapped (see Boston Med. and Surg. Journ., May 31, 1888).
[358] Revue Phil., xxiv. 572 ff.
[359] In the Vierteljahrschrift für wiss. Philos., iii. 294.