Note 106 — Chapter III
Reading edition
The reader will find a great deal about chronographic apparatus in J. Marey: La Méthode Graphique, pt. ii, chap. ii. One can make pretty fair measurements with no other instrument than a watch, by making a large number of reactions, each serving as a signal for the following one, and dividing the total time they take by their number. Dr. O. W. Holmes first suggested this method, which has been ingeniously elaborated and applied by Professor Jastrow. See 'Science' for September 10, 1886.