DEVELOPING THE TRANSFER A rather deep zinc tray is useful for soaking the paper after inking-up. When the inked transfer has been in the water for about a quarter of an hour it is taken out and placed on a sheet of glass or other flat surface, the superfluous mois ture being then lightly blotted off. A second velvet roller, uninked, is now passed over the print, removing most of the unnecessary ink, and leaving only the image. Any remaining ink is very gently taken off with a soft wet sponge, applied with a circular motion. If the ink does ensure perfect contact, the paper being filled in in yellow light or gaslight. The negative must he a bright black and white one, on wet collodion or photo-mechanical dry plates, and free from flaws or scratches. Printing may either be .ex during progress, or judged by actinoincter. The next proceeding is the inking-up, which should be done in a room of even temperature. For this pur pose transfer ink is used, the ink being well distributed over a stone ink slab with a lithographic leather roller, a velvet roller (Fig. 891) being then employed to
take up sufficient ink from the slab. If too stiff, the ink is thinned with a little poppy or almond oil, thoroughly mixing with a palette knife before using ; if too thin, sonic stiff lithographic ink must be added. The dry print is rolled with the velvet roller until it appears of an even light grey tint : it is then placed in cold water. Another method of inking-up is to thin the transfer ink with benzole and turpentine, applying the mixture with a tuft of cotton-wool, or the leather roller alone may be employed. An inking-up not come away easily, the print is re turned to the water for a longer immer sion. When development is finished, the prints are pinned to a flat board and allowed to dry, or placed in a drying oven as previously described. For half-tone transfers a tuft of cotton is preferable to a sponge for removing surplus ink.