| 4. | Silicate of soda | 1 part |
|---|---|---|
| Oxides of metal, such as zinc oxide; litharge, iron oxide, singly or mixed | 1 part |
Very hard and extra strong compositions:
| 5. | Zinc oxide | 2 parts |
|---|---|---|
| Zinc chloride | 1 part | |
| Water to make a paste. | ||
| 6. | Magnesium oxide | 2 parts |
| Magnesium chloride | 1 part | |
| Water to make a paste. |
XI. Flour and Starch Compositions.—
1. The well-known flaxseed poultice sets very tough, but does not stand water or condensed steam.
2. Flour and molasses, made by making a stiff composition of the two. This is an excellent lute to have at hand at all times for emergency use, etc.
3. Stiff paste of flour and strong zinc-chloride solution forms a more impervious lute, and is more permanent as a cement. This is good for most purposes, at ordinary temperature, where it would not be in contact with nitric-acid vapors or condensing steam.
4. A mixture of dextrine and fine sand makes a good composition, mainly used as core compound.
XII. Miscellaneous.—
| 1. | Litharge. | |
|---|---|---|
| Glycerine. |