THE HISTORY OF C'HRONOPHOTOGRAPHY/ 



By Dr. J. Marey, 



Mcinhcr of the Institute of France. 



By ('hronophotography '' is meant a method which analyzes motions 

 ])V means of a series of instantaneous photographs taken at very short 

 and equal intervals of time. By thus representing-, for example, the 

 successive attitudes and positions of an animal, this art renders it pos- 

 sible to follow all the phases of the creature's gait, and even to con- 

 struct exact drawings of it to scale. Of late years, chronophotography 

 has taken another direction — that of the synthesis of motion. The 

 aiiaiytic images are made to appear before the spectators' eyes in uni- 

 form .sequence, so as to reproduce the appearance of the motion itself. 

 Ever3^body is familiar with such animated views. 



The International Exhibition of 1900 enabled us to ))ring together 

 the documents relating to the invention and successive improvements 

 of chronophotography. 



PART I. 



DESCRIPTION OF THE APPARATUS. 



The principal instruments which, in the course of the development 

 of chronophotography, have been devised by those who have pursued 

 this :irt were collected in a large show case (fig. 1).'' They were 

 arranged according to the dates of their several inventions. In addi- 

 tion four large frames contained photographs resulting from the 

 application of chronophotography to various branches of science. 



Xo. 1 is Janssen's astronomical revolver, invented by that astron- 

 omer in 1873 in order to show successive positions of the planet 

 Venus near the limb of the sun at her transits. 



At the focus of a telescope pointed at the sun was a photographic 

 camera, and the sensitive plate, which was circular, turned about its 

 center by leaps, so as to bring into the field a dift'erent portion of its 



"Translation from "Exposition d'instruinents et d' images relatifs tl I'Histoire tie 

 la Ciironophotographie, ]>ar le Docteur Marey, Membre de I'Institut," printed in 

 l)aniphlet entitled Musee Centennal de la Classe 12 (Photographie) a 1' Exposition 

 rniverselle Internationale de 1900 a Paris — Metrophotographie and Chronophoto- 

 graphie. 



^ Photochronography was the form of the word originally employed by the writer, 

 but it has been modified in conformity to a decision of the Congress. 



"The exhibits were arranged in chronological order and numbered, but tlie illus- 

 tration (fig. 1) in Dr. Marey's article was on too small a scale to show details and is 

 here omitted. 



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