incandescent lamps, that could be lighted or extinguished from a
distance, by means of conductors. The photographic apparatus, properly
so called, formed of an objective and camera with its sensitized
plate, was inclosed in a cylinder 3½ inches in diameter. By means of a
cord drawn at the mouth of the well, the apparatus could be made to
issue from its vertical sheath, and to pivot around its axis so as
take views in different directions (Fig. 1).

The entire affair was suspended by twelve-foot iron rods, connected
with each other end for end.

In using the apparatus, the operating was done in a shanty, which
served as a dark room. The device was let down into the bore well
until it touched bottom. At this moment a cord was pulled so as to
raise the camera, and then a few moments were allowed to elapse in
order that the apparatus might become immovable. As the objective was
all the time in the dark, it had neither cap nor shutter, but was
unmasked from the beginning of the operation.

In order to form an impression on the plate, it was only necessary to
give light; this being easily done by passing an electric current by
means of a commutator, so as to light the incandescent lamps. At the
end of the exposure, the lamps were extinguished and the entire
apparatus was immersed in darkness. The mean time of exposure was from
four to five minutes. The apparatus was then hauled up, and the
negative developed.

The experiments could be renewed as often as necessary, and the
apparatus be pointed in all directions by turning it a certain number
of degrees by means of a lever attached to the upper rod. In this way