It may be worth while here to add the following simple and economical method of printing, which I have found to surpass in convenience and afford all the advantages of the most expensive printing frames. Four common clothes-pins, such as work with a _wire_ spring supply pressure enough for a 4/4-plate. Lay your prepared paper upon the negative, and next to it about twenty _separate leaves_ of thin common wrapping paper cut to the size of the negative; next a sheet of tolerably stiff and smooth writing paper, and lastly, a piece of glass as a back to the whole. Let the glass back be pushed from the lower edge of the papers about 1/20 of an inch, or just so far as to enable you to pinch the negative and papers with the thumb-nail and forefinger. Attach a pin to each corner and your negative is prepared for exposure. Now, to examine your picture without endangering its displacement:--remove the pins from one end, and place it, face downwards, on a table, the other end with pins attached projecting an inch beyond the edge. Hold down the back glass with the left hand, while with the right you remove the pins and pinch the papers and negative together between the forefinger and thumb-nail. Upon the smooth sheet of paper you can easily slide the back glass an inch from the edge. Hold it there, and on the uncovered margin attach _three_ of the pins with as deep a bite as they will take. You may now examine your picture to within an inch of its margin, as you would turn over the leaves of a book. To replace the back, lay it again on the table and slide the back glass up to the pins before you remove them. The rest of the process is obvious. The minutiæ of my communication may excite a smile with some, but I shall always act upon the principle, that nothing is more out of place than an apology for minuteness in describing manipulations. G. B. C. * * * * * Recovery of Silver from waste Solutions,--from the black Deposit of Hypo Baths, etc. [Sidenote: RECOVERY OF WASTE SILVER, ETC.] The manner for separating metallic silver from waste solutions varies according to the presence or absence of alkaline hyposulphite and cyanides. a. _Separation of metallic Silver from old Nitrate Baths._--The silver contained in solutions of the nitrate, acetate, etc.; may easily be precipitated by suspending a strip of sheet copper in the liquid; the action is completed in two or three days, the whole of the nitric acid and oxygen passing to the copper, and forming a blue solution of the nitrate of copper. The metallic silver however separated in this manner, always contains a portion of copper, and gives a blue solution when dissolved in nitric acid.