Part 2

* * * * *

INTRODUCTION.

In the year 1872, while the Author was engaged in his official duties as Photographer of the United States Government for the Pacific coast, there arose in the city of San Francisco one of those controversies upon Animal Locomotion, which has engaged the attention of mankind from the dawn of symbolical design, to the present era of reformation in the artistic expression of animal movements.

The subject of this particular dispute was the possibility of a horse having all of his feet free of contact with the ground at the same instant, while trotting, even at a high rate of speed, and the disputants were Mr. Frederick MacCrellish and the Hon. Leland Stanford.

The attention of the Author was directed to this controversy and he immediately sought the means for its settlement.

At this time the rapid dry plate had not yet been evolved from the laboratory of the chemist, and the problem before him was to develop a sufficiently intense and contrasted image upon a wet collodion plate, after an exposure of so brief a duration that a horse's foot moving with a velocity of more than a hundred lineal feet in a second of time, should be photographed practically "sharp."

A few days' experimenting and about a dozen negatives, with a celebrated fast trotter--"Occident"--as a model, while trotting at the rate of a mile in two minutes and sixteen seconds, laterally in front of the camera, decided the argument for once and for all time in favor of those disputants who held the opinion that a horse while trotting was for a portion of his stride entirely free from contact with the ground. With a knowledge of the fact that some horses while trotting will make a stride of twenty feet or more in length, it is difficult to understand why there should ever have been any difference of opinion on the subject.

These first experiments of Zoöpraxography were made at Sacramento, California, in May, 1872. A few impressions were printed from the selected negative for private distribution, and were commented upon by the "Alta California," a newspaper published in San Francisco.

Thus far the photographs had been made with a single camera, requiring a separate trotting for each exposure. The horse being of a dark color and the background white, the pictures were little better than silhouettes, and it was difficult to distinguish, except by inference, the right feet from the left.

Several phases of as many different movements had been photographed, which the Author endeavored with little success to arrange in consecutive order for the construction of a complete stride.

It then occurred to him that if a number of cameras were placed in a line, and exposures effected successively in each, with regulated intervals of time or of distance, an analysis of one single step or stride could be obtained which would be of value both to the Scientist and the Artist.

The practical application of this system of photographing required considerable time for its development, and much experimenting with chemicals and apparatus.

It being desirable that the horses used as models should be representatives of their various breeds, and the Author not being the owner of any that could be fairly classed as such, obtained the coöperation of Mr. Stanford, who owned a fine stud of horses at his farm at Palo Alto, and there continued his labors.

The apparatus used at this stage of the investigation was essentially the same as that subsequently constructed for the University of Pennsylvania, the arrangement of which will be described further on.

Some of the results of these early experiments which illustrated successive phases of the action of horses while walking, trotting, galloping, &c., were published in 1878, with the title of "The Horse in Motion." Copies of these photographs were deposited the same year in the Library of Congress at Washington, and some of them found their way to Berlin, London, Paris, Vienna, &c., where they were criticized by the journals of the day.

In 1882 the Author visited Europe and at a reception given him by Monsieur Meissonier was invited by that great painter to exhibit the results of his labors to his brother Artists who had assembled in his studios for that purpose. M. Meissonier was the first among Artists to acknowledge the value to Art design of the Author's researches; and upon this occasion, alluding to a full knowledge of the details of a subject being necessary for its truthful and satisfactory translation by the Artist, he declared how much his own impression of a horse's motion had been changed after a careful study of its consecutive phases.

It is scarcely necessary to point out, in confirmation of M. Meissonier's assertions, the modifications in the expression of animal movements now progressing in the works of the Painter and the Sculptor, or to the fact of their being the result of studious attention to the science of Zoöpraxography.

In the same year, during a lecture on "The Science of Animal Locomotion in Its Relation to Design in Art," given at the Royal Institution (see Proceedings of the Royal Institution of Great Britain, March 13, 1882), the author exhibited the results of his experiments at Palo Alto, when he, with the Zoöpraxiscope and an oxy-hydrogen lantern, projected on the wall a synthesis of many of the actions he had photographed.

It may not be considered irrelevant if he repeats what he on that occasion said in his analysis of the quadrupedal walk:--

"So far as the camera has revealed, these successive foot fallings are invariable, and are probably common to all quadrupeds....

"It is also probable that these photographic investigations--which were executed with wet collodion plates, with exposures not exceeding in some instances the one five-thousandth part of a second--will dispel many popular illusions as to the gaits of a horse, and future and more exhaustive experiments, with the advantages of recent chemical discoveries, will completely unveil all the visible muscular action of men and animals even during their most rapid movements....

"The employment of automatic apparatus for the purpose of obtaining a regulated succession of photographic exposures is too recent for it to be generally used for scientific experiment or for its advantages to be properly appreciated. At some future time the philosopher will find it indispensable for many of his investigations."

The great interest manifested in the results of his preliminary labors convinced the Author that a comprehensive and systematic investigation with improved mechanical appliances, and newly-discovered chemical manipulations, would demonstrate many novel facts, not only interesting to the casual observer, but of indisputable value to the Artist and to the Scientist. This investigation and the subsequent publication in the elaborate manner determined upon, assumed such imposing proportions, and necessarily demanded so large an expenditure, that all publishers, not unnaturally, shrank from entering the unexplored field.

In this emergency, through the influence of its Provost, Dr. William Pepper, the University of Pennsylvania with an enlightened exercise of its functions as a contributor to human knowledge, instructed the Author to make, under its auspices, a comprehensive investigation of "Animal Locomotion" in the broadest significance of the words, (see appendix B) and some of the Trustees and friends of the University constituted themselves a committee for the purpose of promoting the execution of the work. These gentlemen were Dr. William Pepper, Chas. C. Harrison, J. B. Lippincott, Edw. H. Coates, Samuel Dickson and Thomas Hockley.

The Author acknowledges his obligations to these gentlemen for the interest they took in his labors; for without their generous assistance the work would probably never have been completed; the total amount expended--nearly forty thousand dollars--being entirely beyond his own resources. To Drs. F. X. Dercum, Geo. F. Barker and Horace Jayne, of the University, the Author is also indebted for much valuable assistance.

STUDIO, APPARATUS, AND METHOD OF WORKING.

For a proper appreciation of the care taken in the Investigation of Animal Locomotion at the University of Pennsylvania to ensure accurate record of the consecutive phases of the various movements, attention to the system adopted is necessary.

In the diagram, B is the Lateral background; consisting of a shed 37 metres or about 120 feet, long, the front of which is open, and divided by vertical and horizontal threads into spaces 5 centimetres, or about 2 inches, square, and by broader threads into larger spaces 50 centimetres, or about 19¾ inches, square.