THESE processes or methods of reproduction are the outcome of the endeavour to supersede the artist and engraver. They are quite mechanical, or should be; in fact the less evidence there is of any intervention on the part of the operator or maker of a photographic plate, the better it will be for the work which is being reproduced; still, if an artist turns his attention to these processes, the finest results are obtained, even though he must completely efface himself in the work. M. Amand Durand made the best photogravures ever produced because he was an artist. No mere photographic or mechanical engraver ever approached him.

The theory of photogravure and photo-lithography, in the best work, is the same as that of photo-engraving, which is described in a previous Lecture. In photogravure a photograph of a drawing is usually made on a sensitised copper plate; this is coated with some acid-resisting varnish, but when the varnished plate is washed with water or some acid, the varnish covering the picture on the plate comes away, leaving the picture on the bare copper. This is then bitten in exactly the same way as an etching, the success of the plate depending entirely on the artistic intelligence of the person who does the biting. Or else the photographic print is made on the varnish itself just exactly in the same way as for a zinc block; only in this case the picture is washed away and not the surrounding portions; the biting is then proceeded with.

There are also many other processes of photogravure, while heliotype, autotype, Woodbury-type, collotype, are closely allied to it. The word type is probably used simply because by none of these methods can the plates be used with letterpress. All these processes, however, are very complicated, require expensive machinery, are quite outside the field of art, most secret, and, except theoretically, of little importance to you.

A good photogravure, for example, by Amand Durand or Ch. Dujardin is often a most excellent reproduction of a line-drawing or an etching—so good, in fact, as to be almost indistinguishable from an etching. But to endeavour to palm off pen drawings as etchings, when they have been reproduced in some such way, is to act the part of a common swindler.

Photo-lithography is exactly the same as photo-zincography—process block-making. The drawing is photographed on to transfer paper, covered with lithographic ink and transferred to the stone like any other lithograph. This is a mechanical process; there are a number of ways of getting the drawing on to the stone, and the results are described under many names. Collotypes and other varieties of photographic prints are made from gelatine or other films; they require expensive machines to produce, they are all mechanical processes which you could not readily use unless you went into the business, and are quite outside your art.

One is being continually shown processes which are going to revolutionise engraving and incidentally do away with the artist; this has not yet been accomplished. But just as one sees to-day the momentary triumph of the photographer—or rather of the person who is exploiting the poor photographer—one may remember that chromos have not annihilated painting, nor can the photograph ever be anything more than a useful aid to illustration.