nil': i'/:()ai!i':ss of science 



515 



THE PEOGRESS OF SCIENCE 



THE SCIENTIFIC ORIGIN OF MOV- 

 ING PIC TUBES 



Eadweard Muybridge began his ex- 

 periments in instantaneous photog- 

 raphy in California in 1872 and sub- 

 sequently carried them forward at the 

 University of Pennsylvania, which 

 provided him with grants amounting 

 to more than $40,000. We thus have 

 an instance in which scientific investi- 

 gation supported by a university has 

 been the origin of an enterprise of 

 immense practical and commercial im- 

 portance. The annual receipts from 

 moving-picture shows in the "United 

 States are about $150,000,000; a roy- 

 alty of ten per cent, on these receipts 

 would defray the entire cost of all the 

 real university and research work in 

 this country. 



The experiments of Muybridge at 

 the University of Pennsylvania were 

 originally undertaken to study animal 

 locomotion, and in this direction were 

 of much importance, both for science 

 and for art. Painters and sculptors 

 should represent men and animals as 

 they appear to the eye, not as they ap- 

 pear in instantaneous photographs; but 

 the knowledge of the position of the 

 body in movement, first learned through 

 such pictures, is of value to the artist 

 comparable with a knowledge of anat- 

 omy. Several of the original pictures 

 taken by Muybridge are here repro- 



duced from original plates in the pos- 

 session of the University of Pennsyl- 

 vania, by the courtesy of Mr. George 

 Nitzsche, recorder of the university, 

 who has contributed to Old Penn an 

 article describing the methods used. 



On the grounds of the University of 

 Pennsylvania a shed was built, about 

 120 feet in length, painted black with a 

 net-work of white threads. Opposite 

 the shed was the camera-house, shown 

 in the illustration, in which were 24 

 cameras, each having a lens .3-inches in 

 diameter. The cameras were operated 

 electrically by a motor clock, so that 

 twelve successive exposures could be 

 made in one fifth of a second. In 

 some cases three batteries of cameras 

 were arranged so that simultaneous 

 views from different positions were ob- 

 tained. Thus in one of the pictures 

 here reproduced the stride of a walking 

 horse is shown in 36 different photo- 

 graphs, twelve successive positions 

 being reproduced from three points of 

 view. There is similarly shown the 

 front and side views of movements in 

 making a high jump. Instantaneous 

 pictures of animal locomotion were 

 subsequently made by M. Marey in 

 Paris, who used a sensitized film, so 

 that a succession of pictures could be 

 taken with a single lens. Mr. Edison 

 later applied the film to the kinetoscope 

 and to projecting moving pictures on a 

 screen with a lantern. 



Blildi.\(J Showing liATTEur or Twenty- 

 four Cameras. 



I'llUTiiGRArillC (AMERA DlVinED INTO 



Compartments, each having a lens of the 

 same construction, and arranged to cor- 

 respond with tlie compartments in the 

 Electro Pliotographic Exposors. 



