scotograph

Noun

scotograph (plural scotographs)

1. (obsolete, rare) An instrument for writing in the dark, or by the blind.
   • Scotograph or writing-machine for use of the blind1896 January 28, Thomas J. Bennett, Scotograph or writing-machine for use of the blind, US Patent 553504 (PDF version), title
   • In some recent experiments with it at the Blind Asylum at Amsterdam, children of 6 learned very rapidly to write with the assistance of the scotograph, which is the invention of Dr. Nord, but it is especially designed for the use of scholars, etc., who have become blind late in life and still wish...1897 January 16, The Journal of the American Medical Association
2. (obsolete, rare) An impression made on a photographic plate by a radioactive substance without the intervention of any opaque object other than the screen of the plate.
   • "Scotograph" is likely to stick as the popular term for portraits taken by the Röntgen process. It means "shade picture," and its analogy with photograph, which is a "light picture," is sufficiently manifest to help on its vogue.1896, Western Electrician, page 105
   • You will be able to see radiographs, or scotographs, — referring to darkness and shadow ; you will see that shadowgraphs indicate to you any deformity of the roots of the teeth, or any teeth that have not come into position in the arch, or any osseous deformity which may take place in the jaw […]1896, The International Dental Journal, volume 17, page 532
3. An image of a ghost or other apparition appearing on unexposed film.
   • The spirit-faces are sometimes obtained on ordinary paper without the aid of a camera and are called Scotographs.1946, The Kalpaka, page 49
   • What she did produce at times on her own were so-called scotographs, similar to Rorschach effects used in psychiatry; they were the result of briefly exposing sensitive photographic paper to light and then interpreting the resulting shapes.1997, Hans Holzer, Ghosts of New England, page 223