This section is from the "Henley's Twentieth Century Formulas Recipes Processes" encyclopedia, by Norman W. Henley and others.
Add 2 ounces of S. P. C. clarifier (acid bisulphite of sodium) solution to 1 quart of hypo solution 1 in 5.
Add saturated solution of sulphite of sodium to saturated solution of alum till the white precipitate formed remains undissolved, and when the odor of sulphurous acid becomes perceptible.
Mix this solution with an equal bulk of freshly prepared hypo solution 1 in 5, and filter.
This bath will remain clear.
Alum......1 ounce avoirdupois
Citric acid.. 1 ounce avoirdupois
Sulphate of iron, crystals...... 3 ounces avoirdupois
Water...... 1 imperial pint
This should be freshly mixed.
Saturated solution of alum............. 20 ounces
Hydrochloric acid. ... 1 ounce
Immerse negative after fixing and washing. Wash well after removal.