| IV.— | Colcothar | 1 1/2 parts |
|---|---|---|
| Pumice stone | 1 1/2 parts | |
| Graphite | 4 1/2 parts | |
| Bloodstone (red hematite) | 2 parts | |
| Iron filings | 1 part |
These ingredients are finely powdered, washed, and mixed with the following:
| Grafting wax | 2 parts |
| Soap | 2 parts |
| Lard | 2 parts |
| Olive oil | 2 parts |
Naturally the fatty ingredients are to be heated before the solid substances are commingled with them.
The side of the blade to be polished should be treated with the following compositions:
a. Tin ashes (tin putty) rubbed down to a fine powder on a honing stone and mixed with axle grease.
b. Washed graphite mingled with olive oil.
REDUCERS: See Photography.
REDUCING PHOTOGRAPHS, SCALE FOR: See Photography.
REFLECTOR METAL: See Alloys.