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for the space of fifteen minutes from the time the last print was added from the washing water. The prints, if treated as we have described, will be thoroughly fixed, and if examined by transmitted light will appear clear in the white portions, and a general tone through the shadows. Collect the prints in bulk, drain off the superfluous liquid as much as possible, and separate them in a vessel of clean water. At least four changes of water should now be given, separating the prints each time. They should be next placed separately on a sheet of plate glass, or a flat porcelain dish, and pressed with a sponge to remove as much of the water from them as possible, after which they may be put in the washing apparatus. Washinr/ Appliances.—Photographers are more divided in opinion as to which is really the best mode of washing their prints after fixing, than might be expected ; each one avers his method to be correct both in principle and prac tice. Doubtless this arises in some measure through indi vidual circumstances, among them being water supply, quantity of work, and inventive capacity. To mention the scores of contrivances we have seen would be more likely to confuse than to teach ; therefore we will mention two only to illustrate rapid and slow washing respectively. The first of these is Mr. Marshall Wane’s rapid cylindrical washer, described in “ Studios of Europe,” pp. 189-190, and shown in fig. 1. The outside cylinder, A, is simply a casing of tin to keep in the water ; the inside cylinder. B, that revolves, is a few inches smaller than the exterior one, and it is simply a frame-work covered with twine netting. The prints are laid on this netting in the act of washing, the water being supplied by small holes pierced in tubes passing through the drum. Prints washed by means of this arrangement for twenty minutes, after the previous treatment of four changes of water and pressing with the sponge, are not found to contain any trace of the fixing salt. The other form is a simple and effective arrangement intended for slower washing and larger quantities. We believe they are manufactured by Doulton and Co.,, Lambeth, from the design of Mr. W. Pitcher (fig 2). A, water supply. B, zinc cover to fit over C, perforated with fine holes, to allow the water to stream all over the surface of the prints. C, deep glazed earthenware vessel for the reception of the prints, a number of fine holes being made in the bottom for the water to pass through. D, outer vessel, of the same material, fitted with syphon (S), to permit the wash-water being removed from the bottom at regular intervals, dependant upon the rate of supply. Three or four hours’ washing with such an arrangement will be found ample for the removal of the last traces of the salts retained in the pores of the paper after fixation. That is more than can be said of the custom of soaking prints a dozen or more hours in water, with one or two changes at the commencement, and as many at the finish of the soaking. Hypo Eliminators.—To prevent the tedious operation of washing, it has been suggested to change the chemical composition of the salts left in the paper after fixing, and thereby destroy the properly they possess in such a high degree of rendering the print evanescent. It has been shown by many chemists that this result may in a measure be attained by immersing the print, after fixing, in a dilute solution of either lead nitrate, or acetate barium nitrate, can de javelle., or common potash alum. As these eliminators are not so much in favour with every-day practitioners as they are with the experimental portion of the community, we will merely indicate the method of employing them, thereby opening up a field of further research for the student if he desires to avail himself of it. The lead solution is made by dissolving one ounce of lead nitrate or acetate in eight ounces of warm dis tilled water—two ounces of the above solution to each gallon of soft water will be found to be a workable pro portion. A stronger solution will change the tone to a cold slatey colour, and a weaker one will not bring about the required decomposition. That such has taken place may be known by the solution becoming cloudy. The prints should be immersed in the bath for the space of five minutes, keeping them constantly moved about as in toning and fixing. At the end of the time stated, remove them to a vessel of clean cold water, give them three changes in all, separating each time, when they will be ready for drying and mounting. Barium nitrate (BaNo 3 2) is used by adding two ounces of a saturated solu tion of the salt to each gallon of water. Use the same as lead nitrate, or acetate. Eau de javelle is made by boiling a mixture of dry chloride of lime and carbonate of potash in water. With three quarts of water mix half-a-pound of dry chloride of lime, dissolve one pound of carbonate of potash in one quart of water ; mix the solutions, boil for fifteen minutes, and when cool, filter for use. Four ounces of the above solution to each gallon of water, will be a very good, strength to use ; treat in the same manner as lead nitrate, or acetate. Alum-—Make a saturated solution of ordinary potash alum ; of this use four ounces per gallon of water allow the prints to be moved about for ten minutes, then wash in several changes of water. Prints treated this way require to be soaked in water much longer both before and after the immersion in the alum bath than by either of the I other methods.