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 to drain off the excess of solution, and tends to equalize the sensitiveness.

—This will happen if the bichromate solution is too warm, and the tissue kept too long immersed. During summer it is necessary to keep the bichromate solution as cool as possible, and to sensitize in the coolest place that can be procured.

—If a piece of tissue is printed under too heavy a pressure, dark spots or patches appear in the half-tones. This is most apt to occur if the tissue is limp, and the pressure of the back of the printing-frame not only strong, but uneven from coarse padding.

—This arises from the transfer process being imperfectly performed, the paper being either too wet, or too slight pressure used, or the blanket not sufficiently yielding to diffuse the pressure equally over all the surface of the print.

—This will occur sometimes after the print is entirely finished, generally only during cold weather and is caused by sudden changes of temperature from hot to cold, and vice versa, while the developed print is drying. Avoid this.

very certain that both of the varnished surfaces are perfectly dry before putting them together.

The sooner the tissue paper can be separated from the Saxe paper, in the tepid water bath, the better it will be for the picture; and, for this reason, never take into the tepid water bath more than a dozen pictures at one time,