Another evil arising from mounting prints while expanded with moisture is, that in drying the contraction of the paper pulls round the card into a curved form and although by rolling this curvature may be temporarily got rid of, the fiber of the paper is in a strained condition, and the bent state of the mount is, sooner or later, renewed thereby.

To remedy these evils it has been proposed to mount the print when dry, by forcible pressure against a slightly damped card, the back of the print having been previously coated with a cement and dried.  This plan is, to a great extent, successful; but that it does not give absolute immunity from distortion is, I think, evident from the following consideration.  The prints, after being mounted a few days, will show a certain tendency to curl inward.  This curling, I take it, is a measure of the strain upon the print, produced by the more complete return to its original dimensions of the paper photograph.  Probably it would be well to keep the prints a few days after drying, or to subject them to alternations of damp and dryness, in order to facilitate this complete return before being placed upon the card.  The evil of distortion is, however, very slight—­perhaps imperceptible—­compared with that existing when the prints are mounted wet.  I may mention, en passant, that I have found gum much more satisfactory as a mountant than starch paste in what is known as the “dry mounting” system.

The paper which has recently been introduced for producing prints by development upon a gelatine surface does not generally, when dried in the usual way, give so good or so brilliant a surface as that of albumenized paper; but on the other hand it is very easy with it to obtain what is called an enamel surface, by simply allowing it to dry in contact with a prepared surface of glass.  This method of finishing has therefore been much recommended and adopted, but without consideration of the effect of distortion in connection with it.  In an ordinary photograph the print is mounted damp, but in the case of a print squeegeed on to the glass, the paper is saturated and thoroughly swollen, and the use of the squeegee strains it out to its fullest extent.  By drying in the position in which it has been held by contact with the glass, the distortion becomes fixed, and if the print is mounted while in this state the distortion is made permanent.  How long the strain and distortion remain in an unmounted print, and whether by time and alternations of moisture and dryness the strain would be lost, and if so, whether the brilliant enamel surface would go at the same time, are questions worthy of further investigation and discussion.

For mounting prints upon developed gelatine paper, it has been recommended to cement the edges only, so as to leave the greater part of the print with its enamel surface.  This plan is unsatisfactory, for two reasons, besides the objection on the ground of distortion.  There is a rough-looking margin which spoils the continuity of appearance, especially (as in the specimens I have seen) where the line of cement is not kept at an exact width, but encroaches here and there.