served by astronomers.- John E. Mellish.

** How to Make "Freak" Photographs [110]

The "freak" pictures of well-known people which were used by some
daily newspapers recently made everybody wonder how the distorted
photographs were made. A writer in Camera Craft gives the secret,
which proves to be easy of execution. The distortion is
accomplished by the use of prisms, as follows: Secure from an
optician or leaded-glass establishment, two glass prisms, slightly
wider than the lens mount. The flatter they are the less they will
distort. About 20. deg. is a satisfactory angle. Secure them as
shown by the sectional sketch, using strawboard and black paper.
Then make a ring to fit over the lens mount and connect it with
the prisms in such a way as to exclude all light from the camera
except that which passes through the face of the prisms. The inner
surface of this hood must be

[Illustration: Arrangement of Prisms]

dull black. The paper which comes around plates answers nicely. If
the ring which slips over the lens mount is lined with black
velvet, it will exclude all light and hold firmly to the mount,
Place over lens, stop down well after focusing, and proceed as for
any picture.

** Another Electric Lock [110]

The details of the construction of an electrically operated lock
are shown in the illustration. When the door is closed and the
bolt A pushed into position,

[Illustration: Simple Electric Lock]

it automatically locks. To unlock, push the button D, which act
will cause the electromagnet to raise the latch C, when the bolt
may be drawn and the door opened.
--Contributed by A. D. Zimmerman, Boody, Ill.

** How to Mix Plaster of Paris [110]

For the mixing of plaster of Paris for any purpose, add the
plaster gradually to the water, instead of the contrary, says the
Master Painter. Do not stir it, just sprinkle it in until you have
a creamy mass without lumps. Equal parts of plaster and water is
approximately the correct proportion. The addition of a little
vinegar or glue water will retard the setting of the plaster, but
will not preserve its hardening. Marshmallow powder also retards
the setting. In this way the plaster may be handled a long time
without getting hard. If you wish the plaster to set extra hard,
then add a little sulphate of potash, or powdered alum.

** Enlarging with a Hand Camera [111]

Everyone who owns a hand camera has some pictures he would like
enlarged. I