| Solution A |
|---|
| Pyrocatechin | 2 parts |
| Sulphite of soda, crystals | 2.5 parts |
| Water | 100 parts |
| Solution B |
|---|
| Carbonate of soda | 10 parts |
| Water | 100 parts |
Before using mix 20 parts of Solution A, and 1/2 part of Solution B.
Metol Quinol.—
| Water | 10 ounces |
| Metol | 7 grains |
| Sodium sulphite, crystals, pure | 1/2 ounce |
| Hydroquinone | 30 grains |
| Sodium carbonate, dessicated (or 400 grains of crystallized carbonate). | 200 grains |
| Ten per cent bromide of potassium solution, about | 10 drops |
Amidol Formula.—
| Water | 4 ounces |
| Sodium sulphite, crystals, pure | 200 grains |
| Amidol, about | 20 grains |
| Ten per cent bromide of potassium solution, about | 5 drops |
If the blacks are greenish, add more amidol; if whites are grayish, add more bromide of potassium.
Hypo-acid Fixing Bath.—
| Hypo | 16 ounces |
| Water | 64 ounces |
| Then add the following hardening solution: |
| Water | 5 ounces |
| Sodium sulphite, crystals | 1/2 ounce |
| Commercial acetic acid (containing 25 per cent pure acid) | 3 ounces |
| Powdered alum | 1/2 ounce |
Amidol Developer.—