From this it will be seen that the final stage in the cycle of movements arising from the action of the rifle report upon the microphone, and the relay, is the movement of the paper forming the screen or target. The time during which the picture remains stationary may be varied within certain limits, but normally it is about a couple of seconds. When the paper has moved, obliterating the shot-hole, the brake on the projector is released, the magnetic clutch re-engages, and the film resumes its travel. The ingenious means adopted for stopping and restarting the projector will be appreciated as a great feature of the invention, and though the action may appear to be abrupt, no damage whatever is inflicted upon the film.
One point about this apparatus deserves attention. In the ordinary projector, if the celluloid film is stopped in the gate for a fraction of a second, and is exposed to the light, it flares up instantly, owing to the great heat emitted by the illuminant and the high inflammability of the film. As it is necessary to allow the film to stand still upon the screen in this case, after the shot has been fired, means had to be found to keep it sufficiently cool to prevent combustion. This is done by a radiator arranged around the condenser, which in itself is a special kind of cooling tank.
Another noteworthy point is the way in which a still-life lantern slide is thrown upon the screen when desired. The projector carries two lenses, one for animation, and the other for still-life lantern slide work. The ordinary way of bringing the latter into use is to push the front part of the projector bodily sideways so as to bring the second lens before the condenser and the light. The objection to this method is that the rigidity of the projector is likely to be disturbed, especially after a little wear, with the result that the projection of the moving pictures is apt to become unsteady. In this apparatus a mirror is placed in the lantern and set at an angle of 45 degrees. By this means the light can be diverted and thrown through the lantern slide lens. Thus it is not only possible to throw a still-life slide upon the screen at the instant when a moving-picture scene is completed, but excellent dissolving effects can be obtained.
The Screen Mechanism of the "Life Target."
The movement of the rollers and paper forming the screen is made by means of a solenoid operated by the lantern mechanism.
By permission of the Motograph Co.
Cinematographing Hedge-row Life under Difficulties.
Mr. Frank Newman and his camera concealed in the scrub.