Report to the Surgeon General of the United States Army on the minute anatomy of two cases of cancer / by J. J. Woodward.

  • Woodward, Joseph Janvier, 1833-1884.
Date:
1872
Catalogue details

Licence: Public Domain Mark

Credit: Report to the Surgeon General of the United States Army on the minute anatomy of two cases of cancer / by J. J. Woodward. Source: Wellcome Collection.

Provider: This material has been provided by The Royal College of Surgeons of England. The original may be consulted at The Royal College of Surgeons of England.

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    negatives in inks of a permanent character. These processes are indeed as yet far from perfect, hut several of them have already reached such a degree of excellence as to be very suitable for the reproduction of photographic negatives of microscopical images. In the United States two such methods may be said to be in successful operation, viz: The Woodbury process, and the Albertype process. A detailed account of these processes would be out of place here, hut a few brief remarks are required. The Woodbury method consists essentially in the production from the ne'j:ative by the action of light, of a relief surface of gelatine, from which a metal “intaglio” is produced by pressure. In this a series of gelatine films colored by any suitable permanent pigment are formed by mechanical means, and these con- stitute the prints. Like silver pictures the Woodbury prints require to be mounted on sheets of card board or stiff paper, and this of course adds to the expense. Moreover, if the mount is thick it is ill adapted to binding. Of late, however, films of great flexibility have been produced, which are supported on mounts not much stiffer than ordinary plate paper, and therefore quite suitable for book purposes. In the United States this process is employed by the American Photo-relief Printing Company, No. 1002, Arch Street, Philadelphia, under the supervision of Mr. John Carbutt, who has reproduced throe of my negatives of microscopic objects, viz.: A photograph of a section of ovary magnified 400 diameters, of which five hundred copies were printed, mounted on stiff card board, and used among the illustrations of my report on photographing histological preparations by sunlight; a photograph of Amjililpleura pdlucida, in illustration of a paper published in the “American Naturalist” for April, 1872, and a photo- graph of two frustules of Triceratium fimhriatum, in illustration of a paper published in the Chicago “Lens” for April, 1872. Large editions of the last two prints were struck off for the Journals named. They were mounted on plate paper. In quality these prints were almost fully equal to fine silver prints, which they closely resembled, but the editions were much more uniform than would have been possible had silver prints been used. The cost, moreover, was considerably less than that of silver prints, and the negatives were returned to me wholly uninjured, while they would have been much damaged if not quite destroyed had an equal number of silver prints been made from them. The Albertype process is employed in New York by the Photo-Plate Printing Company, under the supervision of Mr. E. Bierstadt, No. 932 Broadway. In this process a printing surface (not a relief) is produced on a gelatine film by the action of light, through the negative, on certain chemicals contained in the film. The surface thus produced, when properly inked, yields in the press an impression on paper, in which the details of the original negative are very well preserved. The prints may be made on either plain or enamelled paper; in the latter case they closely resemble silver prints on albumen paper, in the former they are like silver prints on plain paper. In either case they give a clean white margin, and therefore do not require to be mounted as Woodbury prints do, but are at once ready for binding. More- over, proper descriptive lettering is readily added to the plate. If suitable ink is employed the prints are as permanent as lithographs or other engravings. Two of my negatives were placed in Mr. Bierstadt’s hands for reproduction, and the illustrations of the present paper are the results. These plates very fairly represent the original negatives. One of them is on plain, one on enamelled paper. The latter more closely resembles an albumen print from the negative than the former does, but the enamelled paper has a certain glare, and I observe that it easily cracks if crumpled. It is a question how far these disadvantages counterbalance its advantages. I place the two prints side by side, and should be glad to hear comments on their respective merits. I may add that the prints of the edition of these two plates are not so uniform as'the Woodbury prints above alluded to. Some are much darker, some much lighter than the standard desired. I can not say, however, that this irregularity is as great as is usually the case with silver prints. In cost the Albertype prints, paper included were rather cheaper than the unmounted Woodbury prints.