On the conversion of a photograph into a line drawing

The making of suitable drawings for reproduction has always been a problem, especially in laboratories which do not command the services of a competent artist. The modern recourse to a useof photography and photo-micrography with subsequent reproduction in halftone, while greatly reducing the labor of preparation, has not produced pictures uniformly satisfactory in simplicity and definiteness. Wax models do not readily lend themselves to photographic methods. Photographs of anatomical dissections do not prove sufficiently clear for easy interpretation after having been subjected to the necessary reduction. The process of line drawing on the other hand leaves nothing to be desired in clearness, since there needs to be depicted only what seems to be essential. Still the execution of suitable drawings from such subjects as those above mentioned requires considerable artistic ability and no little valuable time. As is well known the cost of reproducing photographs and drawings in half-tone is much greater than that of reproducing line drawings in black and white. With these considerations in mind it has seemed that a means for more generally utilizing the line method would be welcome, if, at the same time, it might be possible to eliminate some of its delllands on time and artistic skill. At the suggestion of Dr. Huber a method which has been in use for many years by commercial artists and engravers, and known as the ‘silver print’, has been adapted to the use of scientific illustrators. In brief the method is: 1) To produce a passable negative of the model, dissection or other object to be pictured. 2) Print from this negative an enlargement of suitable size on bromide paper.’ 3) Trace outline of print with waterproof ink and fill in shaded portions by stippling, or by a few lines judiciously placed. 4) Bleach out all traces of photograph. In making the initial negative only the ordinary precautions of careful lighting, proper orientation, etc., are necessary. The conceal-