| Distilled water | 18 | ounces. |
| Hyposulphite of soda | 3 | ounces. |
| Nitrate of silver | 60 | grains. |
The following method should be observed in preparing this last mixture, viz.:—dissolve the three ounces of hyposulphite of soda in sixteen ounces of the water and the sixty grains of nitrate of silver in the remaining two ounces; then pour the nitrate of silver solution into that containing the hyposulphite of soda, stirring the mixture continually until all is well mixed.
After the print has remained in the toning solution for the specified time, it should be taken out and well washed in several changes of clean water, and dried and mounted in any of the usual ways.
With a few general remarks I will close this, perhaps, too long communication. It should be a point in the practice of every one who desires success in any process, to maintain a strict observance to cleanliness; this is one point in which most persons fail, and it cannot be too strongly impressed upon the minds of manipulators. It should be understood that the foregoing process is complete in itself, and is not to be confounded with any other method. The collodion is adapted for the nitrate of silver bath, and the bath for the collodion; and no one should use other preparations of collodion and silvering solution, except they do so with the full expectation that it will be at the loss of either or both of the preparations employed.
Allow me, through the columns of your invaluable Journal, to say to those who may read the foregoing process, that if they find (as I have) my process to prove profitable to them, I shall consider myself amply repaid if they will, through the same medium, contribute to our stock of information by giving an account of their experiments. I feel quite confident that some of the amateurs, with whose reputation I am already acquainted, and of whose private works in photography America has cause to feel proud,—could furnish interesting, useful and valuable information upon this subject. Such men, for instance, as G. B. C, of Md. (who has already made a good beginning), G. W. D., of the same place, and Mr. G. G., of Pa. Friends and co-laborers, shall we hear from you? I pause for a reply!
I look with interest upon every stroke of the pen from your able correspondent G. M., of Washington, whose specimens of photographic engraving you recently had the kindness to show me. I assure you, it did not a little astonish me to witness the surprising truthfulness with which the details were presented.
Helio.