If the amateur does considerable developing and printing he should save the following waste papers, water and baths; if he does but little with his camera, the slight saving will hardly be worth the trouble and time required: The clippings from paper or prints containing silver (before toning),such as albumen paper, plain, bromide and photo-chloride paper, and cotton brushes used for sensitizing plain paper. These should be carefully burned from time to time, as a sufficient quantity accumulates,on a clean shovel, or in an iron pan, and ashes saved.
The first two waters used for washing plain and albumen silver prints should be poured into an earthen glazed jar, and when this is nearly full, the water is to be acidified by adding muriatic acid. A saturated solution of common salt is then added (a small quan tity will be sufficient), which will precipitate the silver to the bottom of the jar as chloride of silver. This should be allowed to stand until all the silver is down, when the water can nearly all be dravvn off with a siphon, or carefully dipped out, care being taken not to stir up the silver. The chloride can then be scraped out and washed in clean water, and added to the ashes from the paper after drying.
A jar should also be kept to preserve old fixing baths. When
this is nearly full, sulphuric acid is added to the solution to acidify it, and:the silver precipitated by the addition of a saturated solution of sulphide of potassium. This must be done in the open air, as the odor is very offensive. When the silver has all settled, the solution should be drawn off as before, and the deposit scraped up, washed and dried, and kept in a special box by itself.
When a considerable quantity of these residues has accumu lated, it can be sent to a silver refiner for reduction. If the ama teur wishes he can himself reduce the silver from the paper ashes and the wash-water residues in the following manner: We use for this purpose a small blacksmith's forge, which forms a part of an amateur work-shop. We take the ashes and wash-water residue, weigh them, and mix very carefully with twice their weight of sal soda, and a like weight of carbonate of potash. This mixture is then put in a crucible, which is placed in the forge and kept at a white heat till the mass is entirely liquid, after which it is allowed to cool. When cold, the crucible is broken, and out comes a small button of silver. It is well worth trying, and the small button will seem worth its weight in gold.