A Manual Of Photography

THE COLLODION PROCESS. 271 cut in it, extending nearly the whole width of the camera, and as far in as the edge of the gutta percha tray. “This opening is intended to admit, when the camera is in use, a light wooden case containing the glass hath, focusing frame, stock of glass, and paper required in the process. “There, are various other little contrivances which I have not specified; such as a drawer for the pictures, a shelf for bottles, &c. “Illis form of camera will admit of the following manipu- lation. Having placed it upon a stand pointing to the object to be taken, the hinged door at the back is opened, and the bath is three parts filled with the solution of nitrate of silver ; a plate of glass is then taken from the cell, and cleaned if necessary. “The collodion is poured on in the manner previously de- scribed; when the film has set a little it is immersed in the nitrate of silver bath, and the lid of the bath is closed down upon it. The next step is to obtain the focus with the ground glass : this can be done whilst the collodion is becoming iodized. “ After adjusting the sliding frame to the proper focal dis- tance, the camera must be closed, and the rest of the process conducted by passing the hands through the sleeves, and placing the eyes close to the aperture in the back of the camera, and drawing the black cloth over the front of the head. “By the aid of the yellow light admitted from the top, the operator can carry on the rest of the process. The plate is now ready for the action of light, and is taken from the bath ; or the bath itself, with the plate in it, is placed in the sliding frame, a he refracted image is at once thrown upon the sensitive plate. After the requisite exposure, the plate is taken from the bath, and the picture is developed with the solution previously described. The progress of this operation can be seen by aid of the yellow light, keeping the eyes close to the aperture behind. "When, from experience, the picture is sufficiently brought out, a little water is poured on the glass to wasli off the deve- loping solution, and the drawing is partially fixed by the appli- cation of a small quantity of a solution of common salt. " The drawing may now be removed from the camera without fear of being injured by light, and the remainder of the ope- rations can be conducted outside the camera. “If the film is sufficiently strong to bear removal from the glass, the following procedure is adopted. The plate of glass 18 placed horizontally upon the back lid of the camera, which