This section is from the book "Complete Self-Instructing Library Of Practical Photography", by J. B. Schriever. Also available from Amazon: Complete Self-Instructing Library Of Practical Photography.
Plural of Formula
The changing of a liquid to a solid by the influence of cold.
(See Chalk, French.)
(See Bed, Swing.)
The largest available opening of a lens.
A clay usually of a greenish tint. Absorbs grease and is useful for cleaning purposes.
A conical-shaped vessel terminating at the smallest end in a spout. Used for pouring a liquid into a vessel having a small opening. Also for filtering liquids through filter paper.
The act of melting or making a solid liquid by means of heat.
(See Acid Gallic.)
An English measure of capacity. It is equal to four quarts. Gamboge.
A vaporous substance not condensed into liquid form at ordinary temperature.
A slow bromide paper which can be handled in ordinary gaslight.
A pure, brittle, transparent, tasteless glue. Swells in cold water, but will not dissolve until heated. The melting point varies with the quality of the gelatin. One of the most useful materials employed in photography. Practically all plates are coated with an emulsion whose basis is gelatin; also used in the emulsions on various sensitive papers.
A term used with reference to the representation of some phase of common life, such as a rural or village scene. It of necessity must include one or more human figures. It is entirely foreign to portraiture as commonly considered, for the subject should be occupied with some familiar work. In brief it is producing a picture that tells a story.
A hard, brittle, transparent substance used as a support for dry plate emulsions, in manufacturing of lenses, etc.