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 to a heavy rolling pressure, and then put aside to dry.

The quality of the cardboard and the exact condition of dampness are of considerable importance. It must be perfectly moistened all over, as, if any point or patch were omitted, the adhesion of the print in that place would not be secured. There should be an absolute film of water on the surface, so that as each part is submitted to the rolling pressure, a wave, infinitely small, however, is driven before the pressure, effectually displacing air, and securing perfect contact. It is, however, undesirable to have excess of water. There should be no delay in applying the pressure after the print has been placed in contact with the moistened surface, inasmuch as the gelatinous, although insoluble image, by absorbing moisture and becoming soft, might, under the heavy pressure, lose something in sharpness.

As each print is passed through the rolling-press, it is placed upon the last, and when the pile is completed, a weight is placed upon the whole heap. By adopting this course, the prints dry without warping or cockling; and at the expiration of about twenty-four hours the print is ready for the final operation.

This consists in removing the paper which has supported the image during the operations of developing and washing. The picture must be quite dry before the operation is attempted. A piece of clean cotton-wool is saturated with pure benzole, and the caoutchouc-coated paper which covers the print is rubbed pretty hard with it. An edge of the caoutchouc-coated paper is then gently raised with the point of a blunt knife, care being taken to commence at a black part of the picture where the film of the compound forming the image is thickest. The raised edge is then taken hold of, and pulled so as to tear it gently and steadily off the print. Instead of