These stock developers usually come in dry salts, which must be dissolved and mixed. All of this work must be done in the light so we can see that we are getting the proper proportions and that the chemicals are thoroughly in solution. The developing trays should be washed thoroughly and placed conveniently at hand so that we can find them in the dark. In addition to developers we must have what is called the “hypo” fixing bath. This is a solution of hyposulphite of soda, a chemical which is used in development and which renders the plate no longer sensitive to light, but dissolves that part which has not been acted upon by the developer. The hypo should be in a tray or box placed conveniently at hand but not so located that it will be liable to become mixed with the developer or in any way to splash or spot the plate. We must always wash the hands thoroughly after immersing a plate in the hypo before handling a fresh plate, as a very few drops will ruin a negative. After we have prepared the hypo and the developer we are ready to develop the plate. Place it face side up in the tray and quickly pour the developer over it, being sure that the solution covers the surface immediately, to avoid unequal development. While we should not develop in a strong red or yellow light we can at least place our tray in such a position that we may watch the process of bringing up the image out of the creamy surface of the plate. This is the most fascinating part of photography. First the high lights will appear and then the shadows, and then after an instant the whole image will come into view and then begin to fade away. To know at what point development should stop will only come by experience with negatives of all sorts of classes. Generally speaking, when the image fades from view and begins to appear through the film on the glass side we should wash it quickly and immerse it in the hypo. The “fixing” in hypo will take probably five minutes and should be continued until the white coating is thoroughly dissolved. The plate may then be brought safely to the light and should be washed thoroughly either in running water for half an hour or in at least twelve changes of fresh water. Care must be taken not to touch the film side of the plate during development or fixing, as the gelatine coating becomes very soft and will show the slightest scratch or abrasion. We must dry the plate away from dust, sunlight, or artificial heat. After it is dry we are ready to make a print.