Gallo-nitrate of Silver.—Can you inform me what the true nature of the decomposition is which takes place after a short time in the gallo-nitrate solution of silver? and if there be any ready means of rendering the silver it contains again available for photographic use?
Sir W. Newton, in the description of his calotype process, says: "Bring out with the saturated solution of gallic acid, and when the subject begins to appear, add the aceto-nitrate of silver solution." Which way of doing this is the best,—mixing the two solutions together and applying them to the paper; or applying the paper, when wetted with the gallic acid, to the silver solution?
T. L.
Replies to Minor Queries.
Verney Note decyphered (Vol. vii., p. 568.).—I am extremely obliged to Mr. Thompson Cooper for his decyphered rendering of Sir Ralph Verney's note of a speech or proceeding in parliament. The note itself is not now in my possession, but I have requested the owner to be good enough to re-collate it with the original, and if any mistakes should appear in the copy, or the printing (which is very likely), I will give you notice of the fact, that the doubtful words in Mr. Cooper's version may, if possible, be set right.
Students in the art of decyphering may be pleased to have the key to the cypher recorded in
your pages. I therefore give it you as discovered by Mr. Cooper, and beg, in the strongest way, to reiterate my thanks to that gentleman.
| 2, | 3, | 4, | 5, | 6, | 7, | 8, | 9, | 10, | 11, | 12, | 13, | 14, | 15, | 16, | 17, | 18, | 20, | 22, | 27, | 28. |
| f, | r, | k, | t, | b, | h, | s, | w, | c, | g, | p, | d, | a, | e, | i, | o, | u, | l, | x, | m, | n. |
The cyphers (if any) for j, q, y, z have not been discovered, and the numbers 1, 19, 21, 23, 24, 25, 26 remain unappropriated.