Plain directions for obtaining photographic pictures upon waxed and albumenised paper and glass, by collodion and albumen : including a third edition of Le Gray's Treatise on photography, a description of the stereoscope and the manner of taking pictures suited for it : also, the process for copying microscopic objects, &c. (1852)
Heisch, Charles, editor, Le Gray, Gustave, 1820-1884. Nouveau traité théorique et pratique de photographie sur papier et sur verre. English · London : T. Willats · leaf 66
64 painting, though conducted with the greatest art, and finished to the last perfection, both with regard to its contours, its lights, its shadows, and its colours, can never show a relievo equal to that of the natural objects, unless these be viewed at a distance and with a single eye.’ For,’… … A, all objects in the space behind it, included as it were in a shadow ECF cast by a candle at A, are invisible to the eye at A ; but when the other eye at B is opened, part of these objects become visible to it ; those only being hid from both eyes that are included, as it were, in the double…
Photography · Collodion process
Internet Archive · Getty Research Institute · Public domain (published before 1931). Free to use for anything.
