This section is from the "Henley's Twentieth Century Formulas Recipes Processes" encyclopedia, by Norman W. Henley and others.

To prepare the following approximately correct solutions, dissolve the amount of medicament indicated in sufficient water to make one imperial pint.

For 1/50 per cent, or 1 in 5,000 solution, use 1.75 grains of the medicament.

For 1/20 per cent, or 1 in 2,000 solution, use 4⅜ grains of the medicament.

For 1/10 per cent, or 1 in 1,000 solution, use 8| grains of the medicament.

For 0.25 per cent, or 1 in 400 solution, use 21⅞ grains of the medicament.

For 0.5 per cent, or 1 in 200 solution, use 43.75 grains of the medicament.

For 1 per cent, or 1 in 100 solution, use 87.5 grains of the medicament.

For 2 per cent, or 1 in 50 solution, use 175 grains of the medicament.

For 4 per cent, or 1 in 25 solution, use 350 grains of the medicament.

For 5 per cent, or 1 in 20 solution, use 437.5 grains of the medicament.

For 10 per cent, or 1 in 10 solution, use 875 grains of the medicament.

To make smaller quantities of any solution, use less water and reduce the medicament in proportion to the amount of water employed; thus 0.5 imperial pint of a 1 per cent solution will require 43.75 grains of the medicament.

Continue to: