you may
have taken snapshots. But there is a difference. Where you take one
picture in a second, the moving picture camera takes sixteen. That is
the uniform rate maintained, though there may be exceptions. And in
your camera you take a picture on a short strip of celluloid film, or
on a glass plate, but in the moving picture machine the pictures are
taken on a narrow strip of celluloid film perhaps a thousand feet
long.

The camera consists of a narrow box. On one side is a handle, and
there is a lens that can be adjusted or focused. Inside is varied
machinery, but I will not tire you with a description of it.
Sufficient to say that there are two wheels, or reels. On one--the
upper--is wound the unexposed film. One end of this film is fastened
to the empty, or lower, reel. The film is passed back of lens, which
is fitted with a shutter that opens and closes at the rate of sixteen
times a second.

Turning a handle on the outside of the camera operates it. So that
when the scene is ready to be photographed the actors, whether men or
animals, begin to move. The handle turns, and the unexposed film is
wound from one reel to the other, inside the camera, passing behind
the lens, so that the picture falls on it in a flash, just as you
take one snapshot. But, as I have said, the moving picture camera
takes snapshot after snapshot--sixteen a second--until many thousands
are taken, so that when the pictures are shown afterward they give
the effect of continuous motion.

The film is moved forward by means of toothed sprocket wheels inside
the camera, the shutter opening and closing automatically.

When the reel of film has all been exposed, it is taken to the dark
room, and there developed, just as a small roll from your camera
would be. This film is called the negative. From it any number of
positives can be made, all depending on the popularity of the
subject.

To make positives, the negative film is laid on another strip of
sensitive celluloid of the same size. The two films are placed in a
suitable machine, and then set in front of a bright light. The two
films are then moved along so as to print each of the thousands of
pictures previously taken.

The positive film is then developed, "fixed" to prevent it from
fading, and it is then ready for the projecting machine. This latter
is like the old-fashioned stereopticon, and by means of suitable
lenses, and a brilliant light, the small pictures, hardly more than
an in