To six ounces of finely pulverized starch, add one fourth ounce
of dry iodine.

Use.--Same as the dry iodine alone.

The same combination may be made with lime, magnesia and other substances.

Concentrated Solution of Iodine for First Coating.--It may appear
strange 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.