Page:Popular Science Monthly Volume 62.djvu/578

572 pigment tissue for the red and yellow positives, that is, the tissue used with the green and violet-light negatives is charged with the complementary inalterable red and yellow pigments. The pigment tissue, of whatever color, is sensitized, exposed and developed in the usual way with some modifications made to facilitate the manipulation during the development, transference and subsequent superposition of the films.

The yellow positive is made first and transferred to gelatine-coated paper which forms the final support of the photograph, the red positive is next made and before drying is superposed on the yellow positive, finally the blue positive is superposed on the other two. The resulting photograph, if the negatives have been of the right density, the pigments of the proper colors and the technique right, is one of which it can be safely said that none made by any other process can be compared with it. The photographs are superior to three-color prints, just as a carbon photograph is superior to a half-tone print, and are superior to an ordinary photograph in the same measure that a carbon print is. Miley's color photographs possess all the richness, depth and permanence of carbon photographs with the addition of color. Unlike the three-color halftone prints, there is no break in the continuity of the color. The texture and minute details of the subject are faithfully reproduced with a naturalness that can only be compared with the originals.

So far the process has been used for still life, landscapes and paintings, but it is possible to take portraits by it, as the time of exposure through the red screen is about fifteen seconds and, with a suitable plate-holder and screenholder, all three plates could be exposed easily in less than thirty seconds. It is hardly necessary to say that the method can be used for the production of transparencies and lantern slides. These, however, have not yet been made.

regret to record the deaths of Professor William Harkness, the eminent astronomer, past president of the American Association for the Advancement of Science; of Dr. Norman Macleod Ferrers, F.R.S.., the mathematician, master of Gonville and Caius College, Cambridge, and of Mr. James Glaisher, F.R.S., known for his work in meteorology and aeronautics.

fellow of St. John's College, Cambridge, has been elected Lucasian professor of mathematics in succession to the late Sir George Gabriel Stokes.—Professor E. F. Nichols, of Dartmouth College, has been elected to a chair of physics in Columbia University.—Mr. Stewart Culin, recently curator of the Museum of Science and Art of the University of Pennsylvania, has become curator of ethnology to the Museum of the Brooklyn Institute of Arts and Sciences.— The Lucy Wharton Drexel medal of the University of Pennsylvania was presented to Professor F. W. Putnam at the Founder's Day celebration on February 21.—Dr. Albert B. Prescott, professor of chemistry in the University of Michigan, has been given the degree of LL.D. by Northwestern University.