In this manner small objects can be photographed without
any deep shadow on one side. The bottom cross and ells should be
corked so as to prevent any slipping and damage to the floor.
** Home-Made Pocket Lamp [149]
A simple and safe pocket lamp that will last for about 6 months
without extra expense can be made at home for a few cents.
Have your druggist take a strong vial of clear glass, or a pill
bottle with screw or cork top and put into it a piece of
phosphorus about the size of a pea and fill the bottle one-third
full of pure olive oil that has been heated for 15 minutes--but
not boiled. Cork tightly and the result will be a luminous light
in the upper portion of the bottle. If the light becomes dim,
uncork and recork again. The lamp will retain its brilliancy for
about 6 months. This makes a perfectly safe lamp to carry. These
lamps are used by watchmen of powder magazines. Care should be
exercised in handling the phosphorus, as it is very poisonous.
** How to Make a Tangent Galvanometer [150]
Secure a piece of wood 1/2 in. thick and cut out a ring with an
outside diameter of 10-1/2 in.
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