317. Preparing Plain Glass

Preparing Plain Glass. If a brilliant surface is desired, plain plate-glass must be used; and after waxing in the usual way, and just before using, the waxed surface should be polished with a dry flannel cloth, by rubbing lightly over the waxed surface. Any moisture coming in contact with the flannel or wax on the plate will ruin the surface. If only plain glass can be had and a matt surface is desired, the plain glass may be waxed and polished in the usual way, but as soon as polished must be flowed with plain collodion. This collodion may either be obtained from any stockhouse, or may be prepared as follows:

318. Collodion

Collodion.

Alcohol .....................................

16

ozs.

Ether........................................

16

ozs.

Gun-Cotton ....................................

3

drs.

Dissolve the gun-cotton in ether and then add the alcohol. Great care must be exercised in handling gun-cotton, as it is very explosive and must be kept away from fire.

319. This should be mixed in a three-pint bottle and kept in tightly corked bottles-glass stoppered preferred. Part of the stock should be filtered into another dry bottle, ready for use. The plates being carefully dusted with a dry camel's-hair brush, are then flowed with the collodion, by holding the plate between the thumb and index finger, allowing it to rest upon the edge of second finger. With the right hand pour on a liberal quantity of the collodion, starting at the farthest corner from you, gradually tipping the plate so the collodion will spread evenly all over, and finally drain back into the bottle. Rock the plate gently from right to left. Then place the plate in the rack for a minute, or until the collodion sets, not dries. This will insure even coating.

320. Next, place the plate in clean water for fifteen to twenty minutes, as it is important that all the ether and alcohol be removed from the film. If any remained these liquids would cause spots and stains. We, therefore, advise rinsing all collodionized plates under the tap for a minute or so and finally set in the rack to dry.

321. First Transfer On Glass

First Transfer On Glass. Into a good-sized tray, half filled with water, and made slightly alkaline by adding a few drops of liquid ammonia, immerse the printed tissue, exercising care in having the fingers perfectly dry when handling the dry tissue or stains will be formed on the surface. The air-bells as they arise on the face or back must be expelled with the camel's-hair brush. After a few minutes' immersion, turn the print face down and slide the collodionized plate under the print. Draw print in contact with glass while under the water. This will prevent air-bells gathering between print and glass. Keeping both together, carefully withdraw them from the water. Place the rubber cloth over the print and glass, and the squeegee into contact, expelling all the air and water. After the print is thoroughly squeegeed cover with a dry blotter, which will absorb all the moisture around the print, thus saving the print from curling during development. Several prints may be transferred before any are developed, and none should be developed unless they be allowed to stand for at least fifteen minutes after squeegeeing, when they are ready for development.