A Developing-Tray Rocker

The tank method of photographic development is acknowledged as the best, yet there are many who, for various reasons, still use the old-style tray method. For those who use the tray, a splendid and simple method that combines the good qualities of both the tank and tray is the tray-rocking device shown in the illustration.

Developing-Tray Rocker to Keep the Liquid in Motion over the Plate Automatically

The rocker consists of a wood box, 13 in. long, 9 in. wide and 1-1/2 in. deep, made of 3/8-in. material, together with a similar box 1-1/2 in. deep, that fits over the other as a light-proof cover. Both are given a coat of black paint.

At the center on the under side of the tray part, a right angle made of strap iron is fastened with screws. On the part projecting down, a hole is drilled to receive a sleeve made of a brass tube which is soldered in place. An ordinary shelf bracket is procured, one end of which is filed and fitted with a strip of metal having both ends turned up slightly. Small-pointed pins are fastened in holes drilled near the turned-up part. The points of the pins serve as a knife-edge for the rocker. The extending end of the strap iron is fitted with a pendulum rod having a weight at the bottom.

The rocker is attached to the wall in a convenient place in the dark room. The tray with the developer and plate is placed in the box, which is light-tight, and the pendulum is started swinging.—Contributed by T. B. Lambert, Chicago.

An Adjustable Bookholder

A very satisfactory adjustable holder for books or letters can be constructed of ordinary materials. A board is used for the base, and two pieces, C, cut from the grooved edges of flooring boards, are fastened on top as shown. A permanent end, A, is fastened to one end of the base. A good-size holder is 19 in. long, 6 in. wide, made of material 3/4 in. thick.