| Add | 1 | gr. or | 1 | m. to | 1 | ounce | of water |
| Add | 15 | “ | 15 | “ | 1 | pint | “ |
| Add | 30 | “ | 30 | “ | 1 | quart | “ |
| Add | 120 | “ | 120 | “ | 1 | gallon | “ |
| To make 1 : 1000 | sol. take | 1 | part of | 1.500 | sol. and | 1 | part water. |
| To make 1 : 2000 | “ | 1 | part of | 1.500 | “ | 3 | parts water. |
| To make 1 : 4000 | “ | 1 | part of | 1.500 | “ | 7 | “ |
| To make 1 : 5000 | “ | 1 | part of | 1.500 | “ | 9 | “ |
To make a 1: 500 solution of formaldehyd add 38 minims of formalin (a 40 per cent. solution of formaldehyd) to 1 pint of water.
A HANDY SOLUTION TABLE WITH
DOMESTIC MEASURES.
| SOLUTION. | DOMESTIC MEASURE. | |
|---|---|---|
| 1 : 1000 | 1 | teaspoon to gallon. |
| ⅒ of 1 per cent. | 15 | drops to quart. |
| 1 : 500 | 2 | teaspoons to gallon. |
| ⅕ of 1 per cent. | 30 | drops to quart. |
| 1 : 200 | 5 | teaspoons to gallon. |
| ½ of 1 per cent. | 1¼ | teaspoons to quart. |
| 1 : 100 | 2½ | teaspoons to quart. |
| 1 per cent. | 1¼ | teaspoons to pint. |
| 1 : 50 | 5 | teaspoons to quart. |
| 2 per cent. | 2½ | teaspoons to pint. |
| 1 : 25 | 2½ | tablespoons to quart. |
| 4 per cent. | 5 | teaspoons to pint. |
| 1 : 20 | 3 | tablespoons to quart. |
| 5 per cent. | 1½ | tablespoons to pint. |
TO PREPARE A 1: 500 SOLUTION.
There are 7680 m. in 1 pint of solution (water); therefore we divide 7680 by 500 as follows:
- 500)7680(15⅗ m. to 1 pint of solution (water).
- 500
- 2680
- 2500
- 1800
- 1500
- 300, or ⅗ of a m.
N.B.—Divide the number of m. in 1 pint by the strength of the solution, and then divide the result by the percentage of original strength of the article.
When original strength of solution is less than 100 per cent., as, for example, formaldehyd, which is 40 per cent., divide the quotient above resulting by the percentage of strength—viz.: