If in summer, you can open your box and set it in sunshine a few minutes; or if in winter, set it under a stove a short time.

The true method, however, is to dry it by means of the chloride of calcium.

It has such a remarkable affinity for water, that a small fragment placed in the open air, even in the dryest weather, soon becomes dissolved.
Take one or two ounces of this chemical, heat it in the drying bath, or in a hot stove, to perfect dryness; place it in a small glass toy dish, or large watch crystal, and set it in the centre of your iodine box.
Take this out and heat to dryness every morning.

Adopt this process, and with your mercury at a high temperature, you will never be troubled with blue pictures.
Young operators are apt to impute all want of success in operating to their chemicals, even though the cause is quite as likely to be elsewhere.

Failure is quite likely to occur from dampness in the buffs, or in the polish; it is therefore necessary to be constantly on the guard in this quarter.