AUG 241917 Price Greenla! JOURNAL OF THE FRANKLIN INSTITUTE DEVOTED TO SCIENCE AND THE MECHANIC ARTS VOL. CLXXX OCTOBER, 1915 No. 4 DEVELOPMENT AND RECENT ADVANCES OF THE TECHNO-GRAPHIC ARTS.* BY LOUIS EDWARD LEVY, Photo-Chemist, Member of the Institute. AMONG the many new influences which are affecting our daily life in this modern time, when the arts are racing with the sciences in a rivalry for progress, not the least are those which are being exerted through the recent advances of the pictorial arts. Up to within the time of these developments all the various methods of pictorial representation could properly be included under the general designation of the Graphic Arts. A picture or design of any kind, on whatever substance it may be wrought, whether drawn with pencil, pen and ink, or crayon, or painted in oil or water colors, or engraved with cutting tools or etched with acids, is essentially a product of Graphic Art. Such are the delineations of animals and fishes found among the remnants of the cave men of the Stone Age of Europe, incised on bone with tools of chipped flint, perhaps a hundred thousand years ago; the designs indented on pottery by the Swiss lake dwellers * Presented at the meeting of the Photographic Section held March 25, 1915. [NOTE.-The Franklin Institute is not responsible for the statements and opinions advanced by contributors to the JOURNAL.] Copyright, 1915, by THE FRANKLIN INSTITUTE. VOL. CLXXX, No. 1078-28 387 of the Bronze Age, some fifty thousand years ago; the colored pictures remaining on the walls of cave dwellings of the same period, and the similar productions of other primitive peoples in Engravings on bone, mingled and superposed. Grotto of Lorthet, Hautes-Pyréneés, France. (Eduard Piette, Revue d' Anthropologie, 1904.) various regions of the globe through all the ages down to the present day. The decorative designs and pictorial representations traced in stone on the walls of temples and monuments that remain to us from ancient Egypt and Assyria, the engravings on stone and other material referred to in various passages of the Bible, the paintings on pottery and on walls that remain from the centuries of classic Greece and Rome, are all of them productions of Graphic Art, and so likewise are the similar remains of the early East Indians and of the pre-Columbian inhabitants of Mexico and Peru. Every such production being complete in itself and affording, moreover, not only a presentation of its subject but also a direct indication of the individuality, the mood of mind and the handicraft of the worker, is naturally to be classed as a product of what may be termed the Manual Graphic Art. Engraving around piece of reindeer antler among remains in Grotto of Lorthet, HautesPyrénées, France. (Eduard Piette, Revue d' Anthropologie, 1904.) But when we come to consider such productions as are not complete in themselves, but require to be supplemented by the printing art, and by that means may be duplicated indefinitely, we must regard them as belonging in a separate category, which has been designated as the Reproductive Graphic Arts. Such are those of engraving on wood, copper, or steel, in which, however, the manual skill of the worker is still the sole and direct agency in the process of production. An indirect agent comes into play when acid is applied to engrave by etching a design which has been drawn by hand on a metal plate, but the skill of the draughtsman is still the essential factor in producing the result. Practically similar is the case in lithography where the design has first to be drawn by hand on the stone before the natural repulsion of fatty substances and water can be utilized in printing from it. Thus the arts of wood and copper plate or steel engraving, etching and lithography, appertain in principle to the Manual Graphic Arts. These various arts had reached a practically complete development when, about 1870, their field came to be invaded by the photoengraving processes and the productions of the hand engravers began to be rivalled by those of the camera. This rivalry of the photographic with the manual graphic arts had its inception as far back as 1813, when an early French lithographer, Joseph Nicéphore Niépce, began working out a process of photo-engraving on lines pointed out by earlier discoveries of the light-sensitive properties of certain resinous gums. After a long series of experiments in this direction he succeeded, by about 1824, in obtaining a lightsensitive medium composed of asphaltum dissolved in a special oil. A film of this solution, flowed on plates of metal and dried, presented a substance which was so changed by the action of light that it became insoluble in the oil. On exposing the sensitized plate to light passing through a transparent paper print the part shielded by the print remained soluble, and when washed away by the solvent the design showed up on the bare metal. The undissolved film of asphaltum protected the plate sufficiently to permit the bare portions being etched, thus producing an intaglio photoengraving. A specimen of these early productions, an etching on a plate of tin, made in 1825, has been preserved in the Niépce museum at his birthplace, Chalon-sur-Saône, and is doubtless the oldest production of a photographic process extant. The asphaltum film was not sensitive enough to be practicable for use in the camera, but Niépce appears to have obtained with his crude instrument, the camera obscura of his day, by very prolonged exposures in brilliant sunlight, some pictures, both on glass and on metal plates, some of the latter silver plated. The pictures thus obtained were negatives, the thin asphaltum film being dissolved out in the development more or less as the exposure had affected it, the lights of the picture being thus represented by the dark undissolved portions of the film and the shadows by the white surface of the silver plate. To reverse the effect, Niépce subjected his finished plates to fumes of iodine, |