Numismatic Literature Definitions

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The Antique Book Exchange has a very detailed glossary, with some entries containing images, of book definitions, abbreviations and book sizes. Rather than duplicate their efforts, this page will provide details on definitions and terminologies which are specific to numismatic literature.

The ABE guide can be found here: ABE Book Glossary.

Contents

Numismatic Literature Definitions

ARTOYPE PLATES

Obernetter, of Munich, invented this improvement on the Albertype in 1878. He uses a mixture of albumen and soluble glass for the foundation film, on which the sensitive film is afterward placed. As this film does not require to be hardened by light, opaque metallic plates may be substituted for the plate glass of the Albertype; otherwise the process is substantially identical with that of Albert.

AUTOTYPE PLATES

Autotype consists in coating a sheet of prepared paper with a mixture of gelatin, bichromate of potass, and carbon, and when dry, exposing it under a negative. On removal from the printing frame, the pigment is moistened with water, and laid, prepared side down, on a support of glass, zinc, or shellac-coated paper, to which a gentle pressure makes it adhere. The paper is then removed, and the print developed by immersion in warm water, which dissolves the unaltered gelatin, but cannot touch the parts rendered insoluble by the light which has passed through the negative. The developed print is again transferred to paper, when the high lights are found to consist of those parts where the gelatin has been completely dissolved, the middle tints of the parts less soluble, and the shadows of the parts quite insoluble. The pictures thus produced are admirable. The chemical durability or resistance to fading is absolute. The reproduction of certain objects, such, for instance, as an engraving may be made a perfect fac-simile of the original. Also called Permanent Photography.

COLLOTYPE PLATES

A lithographic-like process where a substrate (traditionally glass but also metal) is covered with a coat of gelatin sensitized with a dichromate and dried at a specific temperature producing a reticulation of the gelatin. After exposing and developing, this very fine pattern of reticulation will selectively hold the ink, producing very fine half-tone images. Of all the photo-mechanical processes, the collotype is perhaps one of the most useful. It has a variety of names, such as Lichtdruck, Phototype, Photophane, Phototint, Albert-type, Artotype, and many others.

DAGUERREOTYPE PLATES

An ingenious invention, named after the originator, M. Daguerre, a celebrated dioramic painter. The process consisted of exposing silver plates to the vapor of iodine ; these were then placed in the CAMERA OBSCURA, and after sufficient exposure, the light acted upon the iodized surface of the plates, which were then exposed to the vapor of mercury, by which the latent image was developed. The iodide of silver was then washed off by a solution of the hyposulphite of soda, by which further action of the light was stayed, and the image on the plate rendered permanent. Such was the state of the discovery when first made known. Combinations of bromine and chlorine have been introduced more recently, and the result has been a most remarkable acceleration of the process, and the application of the daguerreotype to the obtaining pictures from the life.

HELIOTYPE PLATES

Similar to Collotype. Between the years 1869 and 1872, Ernest Edwards, formerly of London, now of New York, made a number of improvements in collotype printing which resulted in the Heliotype. The most important features of the improvements are the hardening of the gelatine film by chrome alum, and the detaching of it from the support upon which it is first prepared. When completed it is a thin sheet or "skin" of gelatine, tough and flexible. For printing it may be placed on a plate of zinc, or it may be attached to a cylinder. It may be preserved and used for printing, as occasion may demand. A method of printing from a gelatine film upon which the picture has been transferred by photography. From an ordinary negative is made a positive from which a direct impression in ink can be made on a printing press.

HWP

Hand Written Prices

PHOTOGRAPHIC PLATES

Photographic plates preceded photographic film as a means of photography. A light-sensitive emulsion of silver salts was applied to a glass plate. This form of photographic material largely faded from the consumer market in the early years of the 20th century, as more convenient and less fragile films were introduced. Such plates respond to ~2% of light received. Glass plates were far superior to film for research-quality imaging because they were extremely stable and less likely to bend or distort, especially in large-format frames for wide-field imaging. Early plates used the very inconvenient wet collodion process which was replaced late in the 19th century by gelatin dry plates.

PHOTOTYPE PLATES

A relief plate made for printing by photoengraving or photoetching (using a negative of the artwork placed on a sensitized gelatin coated zinc plate). Also a picture printed from such a plate. Also designating the same process as Collotype.

PHWP

Partially Hand Written Prices

WOODBURYTYPE PLATES

The Woodburytype or Photoglyph was invented by W. B. Woodbury. A sheet of bichromatized gelatine is exposed under a negative ; it is then washed to remove the unchanged gelatine that was protected from the light by the negative, and finally dried. This relief film is then placed upon a sheet of lead and forced into it by hydraulic pressure, thus producing an intaglio mould. This mould is placed in a horizontal press and flowed with a solution of warm gelatine colored with pigment. A sheet of paper is then laid upon it, and the excess of colored gelatine is forced out by pressure. The paper print is hardened in a solution of alum. The result is a gelatine pigment picture. A sheet of glass is sometimes substituted for the paper, and transparencies and lantern slides of great beauty are obtained. The Stannotype is a modification in which tin foil, properly backed by electrotyping or otherwise, is substituted for the lead plate. The Photo-filigrane or Photo diaphanic process consists in attaching the gelatine relief to a plate of steel and using it to produce, by pressure, transparencies in white paper, which resemble water marks.