upon the face, as the gelatine is insoluble there. It must, there-fore, be transferred to some support, so as to enable the gelatine to be dissolved away from the back, for which purpose the paper must be removed; and as this transfer would reverse the print - i.e., make the right hand of the picture the left - when a negative taken in the ordinary way is used, a temporary support is required, from which the developed print is again transferred to its correct position. This temporary support may be either a mulled zinc plate, glass, or a specially prepared paper, accord-ing to the surface desired. From the temporary support again the print may be transferred to paper, opal glass, porcelain, metals, ivory, terra-cotta, stone, wood, or other material. The special transfer paper or temporary support is a tough, smooth paper coated with shellac and rolled, and when re-quired for use it is waxed to prevent the gelatine film from adhering permanently to it, the following solution being used for that purpose : -
Yellow resin ... ... ... ... 36 grs.
Yellow wax ... ... ... ... 12 ,,
Turpentine ... ... ... ... ... 2 ozs.
Melt the wax, add the resin and turpentine. The writer has found the substitution of ether for turpentine a decided advantage, as the temporary support can be used immediately; when turpentine is used some hours must elapse after the waxing solution has been applied to the paper, which is done with a tuft of cotton-wool, or flannel, and a fresh tuft of wool being used to polish. A piece of smooth indiarubber cloth or " macintosh," slightly waxed with the turpentine solution, is a very good temporary support. The printed tissue and the waxed temporary support, of whatever nature it may be, are immersed in cold water, till the tissue begins to uncurl and float flat; it is brought into contact, film side downwards, with the temporary support, and both raised together from the water, and then the squeegee is used to bring them into complete contact. They are then placed between blotting boards for five or ten minutes, and immersed in a bath of water at a temperature of 1050 or 1 ioo F. When the pigmented gelatine begins to ooze out at the edges of the paper, strip off the paper upon which the gelatine was spread, and keep washing the print with the hot