Portable Camera for Travellers.—Your correspondent E. S. asks for a clear description of a camera that will supersede the necessity of a dark room. Mr. Stokes has invented one; and in the early part of the photographic exhibition at the Society of Arts it was exhibited. The weight of the camera is only nine pounds, including focussing-glass, lens, shutter, &c. The shutter is so arranged that it will contain from twelve to twenty pieces of prepared paper, each piece between separate sheets of blotting-paper. Light and air are completely excluded, by the paper being pressed by the front portion of the shutter. When required for use, the first piece of paper is placed at the back of the glass. By the assistance of a small hood, the impression is then taken; and, by removing the millboard, the paper will fall back into its place. At the same time another piece can be brought forward, ready for a second picture, before focussing, and so on to the end. The hood is made of India rubber cloth, and answers the purpose of a focussing cloth, without the trouble of removing it from the camera throughout the day. The size of the pictures that can be taken by it is 9½ by 12 inches. It has been tried during the latter part of the last year, and proved most successful.
Philip H. Delamotte.
Bayswater.
The Albumen Process.—I shall be greatly obliged to Dr. Diamond, or any other photographer, by their kindly communicating through your medium their experience with albumenized glass. I have Thornthwaite's Guide to Photography.
I should like answers to the following Queries:
Must the albumen be poured off from the plate after it is spread over the surface, in the same manner as collodion?
Is the plate (while roasting, according to the process of Messrs. Thompson and Ross) nearly perpendicular in the process?
Will the iodized albumen, for giving the film, keep; and how long?
How long will the plate retain its sensitiveness after exciting?
May the same sensitive bath be used for a number of plates without renewing, in the same way as silver bath for collodion?