th the compounds
formed with iodine, bromine, and fluorine.

"On heating the plate, the brown coating of chloride melts into a
translucent enamel, and the heat should be withdrawn when a cherry-red
color is produced. It the heat is continued longer, the plate assumes
a lighter color, and becomes less sensitive; and the enamel will
finally scale off. To produce a picture by the ordinary process of M.
Neipce, unaccelerated, it should be exposed for from three to five
hours to sunlight in the camera, though pictures may be procured by
contact, in from fifteen to thirty minutes."

MULTIPLYING DAGUERREOTYPES ON ONE PLATE.

I have produced some interesting specimens of the Daguerreotypic art,
by exposing in the camera only a portion of the sensitive plate to the
action of light. When on the exposed portion an image is formed, then
taking the tablet into the dark room, change ends and expose the
sensitive portion, and produce another image, developing as usual.
This plan is adapted for taking likenesses for lockets. Two images can
be presented as sitting side by side, by covering half the plate with
black paper, and exposing as before. In this manner we have been
enabled to surprise persons by exhibiting their portrait on the same
plate with a stranger's. Daguerreotypists must be cautious in
practicing this, as it might not be agreeable to the parties whose
likenesses are together, by the above process. It is impossible to
produce an impression without a line being seen where the edge of the
paper prevented the operation of the light.

I have recently seen a fine specimen produced by another plan, which
far exceeds the above, there being no line, or any peculiarity denoting
two exposures. The specimen referred to, was a gentleman represented
on one plate by two full length portraits. This was produced by using
a black velvet for the background. The plate was exposed sufficient
time to produce one impression, and then the gentleman assumed another
position, and is repeated as looking at himself. From the fact that
the time required to develop black velvet being so much longer than
that for producing a portrait, we are enabled to produce the above
interesting results.

DEPOSIT IN GILDING.

Regarding specks from bad water, I would remark that gilding should be
made only with distilled water. Thus made, it produces very little
deposit, even by long keeping. It therefore preserves its original
strength, and