| Sturgeon’s bladder | 8 |
| Gum-ammoniac | 1 |
| Galbanum | 1 |
| Spirits of wine | 4 |
The sturgeon’s bladder is cut into small pieces and steeped in the spirits, and the rest, in solution, then added. It must be warmed again when used.
As this cement will bear long exposure to moisture before being at all injured by it, it can be used as a medium for painting on glass, and thereby producing effects very little inferior, either as regards beauty or durability, to glass itself. The experiment can be easily tried, as any chemist can make up the recipe. When finished, the painting can be coated with liquid silicate of soda, which will give it all the property of glass.
A lime cement for glass is made as follows:—
| Calcined lime | 30 |
| Litharge | 30 |
| Linseed-oil varnish | 5 |
Jewellers’ cement. Extremely strong:—
| Fish-glue solution | 100 |
| Mastic varnish (pure) | 50 |
The fish-glue must first be dissolved in spirits of wine.
To join Glass and Metal, &c.—Stir slacked and powdered lime in hot glue. This sets as a very hard substance. It can be extensively modified and varied for many substances, and used for painting.
Cement for glass:—