Page:Popular Science Monthly Volume 53.djvu/440

This page has been proofread, but needs to be validated.
424
POPULAR SCIENCE MONTHLY.

Peninsula of Eastern Virginia. Pp. 4.—Kenyon, r. C.: The Terminology of the Neurocyte or Nerve Cell. Pp. 3.—Herter, C. A., M. D.: An Experimental Study of Fat Starvation, with Especial Reference to the Production of Serous Atrophy of Fat. Pp. 22, with plates.—Otis, D. H.: Root Tubercles and their Production by Inoculation. Pp. 16, with plate.—Rosse, Irving C, Washington: Brief Mention of Neurological Cases Successfully Treated. Pp. 8.—Stuve, E.: Do Vivisectionists inflict Unnecessary Suffering in their Investigations? Pp. 8.—Williamson, Mrs. M. B.: A Vanishing Island. Pp. 4.

Reye, Theodor. Lectures on the Geometry of Position. Translated and edited by Thomas P. Holgate. Part I. New York: The Macmillan Company. Pp. 248. $2.25.

Shaler, N. S. Outlines of the World's History. New York: D. Appleton and Company. Pp. 417. $1.75.

Smithsonian Institution: Publications available for Distribution. April, 1898. Pp. 20.

Story, A. T. The Story of Photography. New York: D. Appleton & Co. Pp. 169. 40 cents.

Treadwell, Augustus. The Storage Battery. New York: The Macmillan Company. Pp. 257. $1.75.

United States Geological Survey. Eighteenth Annual Report. Part V (continued). Mineral Resources of the United States. 2 vols. Pp. 1400.

University of Tennessee Record. No. 1: Review of 1897. Knoxville. Pp. 66.

Waring, George E, Jr. Street Cleaning in the City of New York, 1895, 196, 1897. Pp. 234.

Wiley, John, & Sons. Announcements of Ladd's Manual of Quantitative Chemical Analysis, and Wells's Short Course in Inorganic Qualitative Analysis.

 


Fragments of Science.

An Episode in the Early History of Animated Photography.—The following interesting letter from Henry R. Heyl is published in the Journal of the Franklin Institute for April: "Among the earliest public exhibitions of photographs taken from living subjects in motion projected by the lantern upon a screen, was that given at an entertainment held in the Academy of Music, in Philadelphia, on the evening of February 5, 1870, and a repetition of this exhibition was made before the Franklin Institute at its nest following monthly meeting, on March 16th, by the writer. The printed programme of this event contains the following allusion to this feature of the entertainment: 'The Phasmatrope. This is a recent scientific invention, designed to give various objects and figures upon the screen the most . . . lifelike movements. The effects are similar to those produced in the familiar toy called the zoetrope, where men are seen walking, running, and performing various feats in the most perfect imitation of real life. This instrument is destined to become a most invaluable auxiliary to the appliances for illustration, and we have the pleasure of having the first opportunity of presenting its merits to our audience.' The subjects exhibited embraced waltzing figures and acrobats, shown upon the screen in life size, while the photographic images were only three fourths of an inch in height. At that day flexible films were not known in photography, nor had the art of rapid-succession picture-making been developed; therefore, it was necessary to limit the views of subjects to those that could be taken by time exposures upon wet plates, which photos were afterward reproduced as positives on very thin glass plates, in order that they might be light in weight. The waltzing figures, taken in six positions, corresponding to the six steps to complete a turn, were duplicated as often as necessary to fill the eighteen picture spaces of the instrument which was used in connection with the lantern to project the images upon the screen. The piece of mechanism, then named the 'phasmatrope,' consisted of a skeleton wheel having nine radial divisions, into which could be inserted the picture holders, each consisting of a card upon which was mounted two of the photo positives, in such relative position that, as the wheel was intermittently revolved, each picture would register exactly with the position just left by the preceding one. The intermittent movement of the wheel was controlled by a ratchet and pawl mechanism operated by a reciprocating bar moved up and down by the hand. It will be apparent that the figures could be moved in rapid succession or quite slowly, or the wheel could be stopped at any point to complete the evolution. In the exhibitions at the Academy of Music, above alluded to, the movement of the figures was made to correspond to the time of the waltz played by an orchestra, and when the acrobat performers were shown a more rapid motion