318 



HISTORY OF CHRONOPHOTOGKAl'HY. 



border at the end of every 70 seconds of time. In that way a scries: of 

 images were obtahied (fig. 2) which showed the successive positions of 

 the planet on the sun. She was seen to penetrate the limb, to cross 

 the disk, and finally to depart; and the interval between the images 

 being known, the velocity of the movement could be measured. This 

 experiment seems to have been the earliest achievement of a chrono- 

 photograph; for though others before Janssen conceived bolder 



Fig. 2. 



attempts, there was, in an exhibition of real things, no place to show 

 plan^ or projects impracticable at the time of their invention. "^ 



No. ^. Afxdysis of the motions of animaU hy the method of Muy- 

 hridge, 1878. — This celebrated photographer of San Francisco suc- 



*In an article on the "Beginnings of the Cinematograph" in Camera Obscura for 

 February, 1901, Mr. Charles Niewenglowski refers to an ingenious idea of 1857 of 

 Charles Adolphe Reville of bringing into a stereoscope a succession of double photo- 

 graphs of the phases of a phenomenon. But for that purpose it would have been 

 necessary to take tiie photographs of the objects in motion, which at that date would 

 have been impossible, except at the lowest velocities. The same article figures an 

 apparatus devised in America about 1861 by Coleman Sellers. It was called a 

 "stereophantascope," and was intended to obtain the same result as Reville. The 

 most remarkable conception was, by all odds, that of M. Ducos du Hauron, wlio in 

 March, 1864, took out a patent for an appantlus for plioiogmphmg any scene vjith all 

 the transformations which it might go through in a given time. How to take the photo- 



