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is composed of:

Bromide of Zinc	150	grains.
Iodide of Zinc	350	grains.
Alcohol	10	ounces.

When the salts are dissolved, filter and add to the collodion.

The filtering is best done by placing a pledget of cotton-wool in the neck of a glass funnel and passing the iodizer through it. To prevent evaporation, lay a glass plate over the funnel.

The iodizer being added to the collodion, shake them up thoroughly and allow to stand for a week to settle, then decant into convenient bottles; this collodion is ready for use in a week, but will improve with age up to six months, after which time it should be mixed with new.

When coating plates with collodion, it is not a wise plan to pour the surplus from the plate back into the bottle from which it was poured. Pour it into another, kept handy for the purpose, the contents of which, at the end of the day’s work, empty into the stock bottle after such a quantity as is sufficient for next day’s consumption has been decanted into the pourer.

The best bottle from which to pour the collodion upon the plate is the tall capped bottle sold by the dealers as collodion pourers. {12}