The best enlargements are made by utilising a room as a camera. The window should be blocked up with a screen in which should be cut an opening just large enough to be covered by the reversing back of the camera -, outside the window, fix, at an angle of 4V, a white board or other reflector, which should be about three times the diameter of the reversing frame, but if the window has a clear view of the sky, the reflector may be dispensed with. Adjust the camera against the opening, with the lens pointing into the room, and insert the slide containing the negative, both shutters being drawn out. The picture should be focussed on a sheet of white paper or board placed on an upright easel or other support, the easel being moved and the lens racked out until the proper focus is obtained. Then cap the lens, place the bromide paper in position, and expose.