The accompanying illustration shows an adjuster for changing the drop of an electric light. The main feature of this adjuster is that it can be removed from the cord at any time. The adjuster is made from a piece of wood, 3/8 in. thick, 2 in. wide and 3 in. long. A 1/4 in. hole is bored in the center near each end of the wood and a slot cut from the holes to the outside edge, as shown in Fig. 1. It is attached to the flexible cord as shown in Fig. 2.

Contributed by J.J. Voelcker; Decatur, Ill.

Making Photographs on Watch Dials

Beat to a foam the white of an egg, with the addition of a little ammonia. Add 9 oz. and 3 dr. of water and beat again. After the egg has settled, filter and let the liquid run over the dial, which has been previously cleaned with ammonia. When the surplus has run off, coat with the mixture and allow to dry.

A sensitive collodion is now produced as follows: Dissolve 9 gr. of chloride of zinc in 5 dr. of alcohol; add 7-1/2 gr. of collodion cotton and 6-1/2 dr. of ether. Shake the whole forcibly.

Dissolve 23 gr. of nitrate of silver in hot water, add 1-1/2 dr. of alcohol and keep the whole solution by heating. The silver solution is now added in small quantities at a time to the collodion, which must be well settled. This, of course, is done in the dark room. After 24 hours the emulsion is filtered by passing it through cotton moistened with alcohol. This durable collodion emulsion is now flowed thinly upon the prepared watch dial, which, after the collodion has coagulated, is moved up and down in distilled water until the fatty stripes disappear. The water is then changed once, and after a short immersion, the dial is left to dry on a piece of blotting paper. It is now ready for exposure. Expose under magnesium light and develop with a citrate oxalic developer, or in the following hydroquinone developer:

Hydroquinone1 dr.
Bromide of potassium6 dr.
Sulphite of soda1-1/2 oz.
Carbonate of soda2-2/3 dr.
Water14 oz.

After fixing and drying, coat with a transparent positive varnish.