range to some of our old operators that an aqueous solution of iodine
can be used for coating the plate and forming the iodide of silver. It
has long been a cry among most operators that it is impossible to
succeed when the iodine box contains dampness. Now this is a great
mistake, and we will here state that in all cases where dampness
appears upon a properly prepared Daguerreotype plate, it is the result
of a different temperature of the metal from the air which surrounds
it. Mr. Senter, of Auburn, was the first of our operators who used a
solution of iodine for coating the plate, and we several years since
saw his results, which would rival the production of any other
operator. A concentrated solution of iodine is prepared by putting
into a common bottle two thimblesful of hyposulphite of soda and a
rather larger quantity of iodine, so that there may be more than
sufficient. Add to it about 40 ounces of common water (heated to 60 or
70 degrees), by little and little, moving, the bottle to warm it, for
fear of breaking. After shaking it a short time, the water is rapidly
and strongly colored. The solution should be poured into a bottle with
a ground stopper, and when cool used for iodizing.

A solution of sufficient strength can be made by moistening or just
covering the iodine with water.

Chloride of Iodine as an Accelerator.--This is probably one of the best
accelerators that can be used for coating the plate for taking views;
it works too slow, however, to meet the wants of the operating room,
yet its use was formerly, for a long time, adhered to by some of our
best professors. In producing views with this, we are successful in
obtaining well-developed impressions, with a depth of tone and richness
of appearance not to be met with in the productions of any other
substances. I give its use as furnished me by an old and experienced
operator, and published in Humphrey's Journal, vol. i. p. 180:

"As the process of using chloride of iodine may be of interest to some
of our subscribers, I take pleasure in giving the following
manipulation. To one ounce of chloride of iodine add two ounces of
water; place this mixture in a coating-box, the same as quick stuff;
coat the plate with dry iodine to a light yellow, or lemon color; then
bring the coating to a deep pink over the chloride. The plate must be
recoated over the dry iodine."

This combination has been very successfully used in one of our most
extensiv