SENSITIZING SOLUTION.
Ammonio nitrate salt3 drams
Alcohol8 drams
Distilled water15 drops
Nitric acid, pure1 drop

Plain Collodion.—Dissolve in a small quantity of ether 1 dram of Canada balsam and 1 dram of castor oil, filter and let evaporate the solution to the consistency of oil.

Of this, add 10 minims to a collodion made of

Alcohol10 ounces
Ether20 ounces
Pyroxyline220 grains
SENSITIVE COLLODION
Plain collodion12 drams
Sensitizing solution6 drams
Nitric acid2 or more drops

Keep this collodion in the dark, as it is quite sensitive.

PREPARATION OF THE PAPER
Arrowroot, pulverized1 ounce
Water32 ounces
Solution of acetate of lead10 drops

Heat to 100 deg. Fahr. and then add four ounces of albumen. The paper is floated on this solution for five minutes and hung up to dry. The sizing may also be applied with a sponge in the manner often described.

The proofs should be slightly over-printed and, before toning and fixing, placed for about ten minutes in the following solution:

Distilled water40 ounces
Acetic acid1 ounce
Hydrochloric acid1 ounce