The ordinary fixing bath consists of one part of hyposulphite of soda to four parts of water. There are various other fixing baths known as acid baths, alum baths, etc. Fixing baths should be kept free from dust and to do this you should fit a cover to your bath. They should also be filtered occasionally. The various plate manufacturers recommend the following fixing baths:

Seed's Chrome=Alum Fixing Bath

No. 1.

Water (3 quarts)................96 oz.

Hypo........................... 2 lbs.

Sulphite of Soda (Crystals)___ 4 oz.

No. 2.

Water...........................32 oz.

Chrome-Alum................... 2 oz.

Sulphuric Acid.................1/4 oz.

Pour No. 2 into No. 1, while stirring No. 1 rapidly. As the Chrome-Alum dissolves slowly a stock solution of No. 2 can be made up.

Cramer's Acid Fixing Bath

No. 1.

Hyposulphite of Soda...........48 oz.

Water (3 quarts)................96 oz.

No. 2. Water...........................32 oz.

Sulphuric Acid, added gradually 1/4 oz.

Sulphite of Sodium Crystals... 4 oz.

Chrome-Alum.................. 2 oz.

After the ingredients are dissolved pour No. 2 into No. 1. During cold weather one-half the quantity of No. 2 is sufficient. This bath remains clear after frequent use, does not discolor the negatives and hardens the gelatine to such a degree that they can be washed in warm water. They should be left in the bath five to ten min utes after the Bromide of Silver appears to have been dissolved, to insure perma nency, freedom from stain and perfect hardening. With the use of tho above described Acid Fixing Bath, there is no danger of frilling, even in tropical cli mates.