Note Y — Chapter XX

Major Waterhouse has published the following ingenious method of transforming a drawing on paper into a photographic negative:—“A tracing, or drawing, is made in lithographic ink on tracing paper, using plenty of ink on the lines. The drawing is then placed on a board over a piece of blotting-paper, and brushed all over with a strong solution of aniline brown in water; when dry it is rubbed over with a tuft of cotton wool soaked in turpentine, which removes the ink without altering the coloured ground. The lines then appear clear on a dark reddish brown ground. The negatives thus obtained are good, but more suited for coarse than fine work.” It may be suggested, why not transfer the drawing direct to stone, and produce the necessary copies by lithography?—Trans.