In certain lines of commercial work such as the photographing of china or other colored objects it is an advantage to be able to show, not only the design but its color as well. And as the customer requires, or at least prefers glossy prints, the way to color these prints in a satisfactory manner has been a problem with many commercial workers.

It is quite possible to do this coloring on the glossy print after it has been squeegeed, using Velox Water Color Stamps or similar colors, but only on condition that the surface of the print is absolutely free from grease and the colors are not used too wet.

The slightest finger mark or other trace of grease on the print will prevent the colors from taking hold properly. And as ferrotype plates must be greased or waxed to prevent prints from sticking, the print should first of all be gone over thoroughly with ether to remove this grease.

Alcohol will not answer the purpose as it appears merely to spread any grease present instead of entirely removing it.Gall is sometimes recommended to make the color take. This is not necessary if the print is thoroughly clean, and it has the disadvantage of precipitating certain colors.

However, putting the color on after squeegeeing does not give quite as good a result as putting it on before, but the problem has been to prevent the colors from running when the print was placed in water preparatory to squeegeeing.

The success of the process lies in the hardening of the print before and after coloring. Prints to be colored should be soaked in a five per cent, solution of phospho-tungstic acid for three minutes, then taken out and all superfluous moisture removed. The Velox Water Colors are then put on with as dry a brush and as little water as possible. The color is put on while the print is damp, but it must not be so wet that the color will run.

The color is put on while the hardened print is moist to enable the colors to soak in better. If the print is hardened and allowed to dry and the colors then put on they remain more or less on the surface and the color has a tendency to run when the print is again moistened.

It is therefore better, especially in the case of large prints, to lay them on a piece of blotting paper previously soaked in the phospho-tungstic acid bath to keep the print moist during the time it is being colored.

After the print has been colored it is placed immediately in the same phospho-tungstic acid bath and then squeegeed directly onto the glass or ferrotype plate. On drying, the gloss of the colored parts will be fully equal to the gloss of the rest of the prints.

Alum, chrome alum or formalin may be used to harden the gelatine, but they are not so satisfactory as the phospho-tungstic acid.

Large prints on artura Carbon Black retain the contact quality.