The following tables of Dr. Sherrard, Ph. C, are simple and require but little explanation. The first table gives percentage solutions, as, for instance, 4 per cent. cocaine muriate solution; the second table gives parts in 1,000 or 5,000, as, for instance, corrosive sublimate 1 in 1,000. The use of the first table is as follows: Run down column 1 until the correct percentage wanted is found, then move to the right along the line until the column is found giving the amount of the fluid measure to be made up; at the intersection will be found the weight of the salt required. For example, suppose it is desired to make 4 fl. oz. of 4 per cent cocaine muriate solution, run down the left-hand column to 4, then along to the right till the column headed 4 fl. oz. is reached. At the intersection of the two will be found 72912, and this is the number of grains needed. It must be remembered that this is the amount of water to take, and not q. s. water to make the volume, and also that these tables are true only for water, and not for alcohol, or any other fluid. The second table is similarly employed. If other amounts of a solution are required than those given in the tables, a simple mathematical calculation will determine the amount of drug or salt required for a specified amount of solution. For example, if 8 fluid ounces of a four per cent. solution is required, follow down the 4 fluid ounce column until opposite 4 per cent.; the number of grains required are 72912. Now, to make 8 fluid ounces, just twice as much (145,824 grs.) is required. For all dispensing and administering purposes in any prescribed doses, the figures thus given are correct. It is therefore clear that if a drachm of a 2 per cent solution be prescribed, exactly 2 per cent of that drachm is the salt in the solution, the other 98 per cent. being the water.

## For Making Any Quantity Of Percentage Solutions

 For each 1 fl. oz.of water take of the drug or salt. For each 2 fl. ozs.of water take of the drug or salt. For each 3 fl. ozs.of water take of the drug or salt. For each 4 fl. ozs.of water take of the drug or salt. For each 5 fl. ozs.of water take of the drug or salt. For each 10 fl. ozs.of water take of the drug or salt. For each 16 fl. ozs.of water take of the drug or salt. To make Grains. Grains. Grains. Grains. Grains. Grains. Grains. I per cent. . 4.557 9.114 13.671 18.228 22.785 45.57 72.912 2 per cent. . 9.114 18.228 27.342 36.456 45.570 91.14 145.824 3 per cent. . 13.671 27.352 41.013 54.684 68.355 136.71 218.416 4 per cent. . 18.228 36.456 54.684 72.912 91.14 182.28 291.648 5 per cent. . 22.785 45.57 68.355 91.14 113.925 227.85 364.56 10 per cent. . 45.57 91.14 136.71 182.28 227.85 455.7 729.12 15 per cent. . 68.355 136.71 205.065 273.42 341.775 683.55 1093.68 20 per cent. . 91.14 182.28 273.42 364.56 455.70 911.4 1458.24 25 per cent. . 113.925 227.85 341.775 455.70 569.625 1139.25 1822.80 40 per cent. . 182.28 364.56 546.84 729.12 911.4 1822.8 2916.48

## For Making Any Quantity Of Solution When Stated In Parts Per Thousand, Hundred, Etc

 For each 1 fl. oz.of water take of the drug or salt. For each 2 fl. ozs.of water take of the drug or salt. For each 3 fl. ozs.of water take of the drug or salt. For each 4 fl. ozs.of water take of the drug or salt. For each 5 fl. ozs.of water take of the drug or salt. For each 10 fl. ozs.of water take of the drug or salt. For each 16 fl. ozs.of water take of the drug or salt. To make a solution of Grains. Grains. Grains. Grains. Grains. Grains. Grains. 1 in 1000 . . .4557 .9114 1.3671 1.8228 2.278 4 557 7.291 1 in 500 . . .9114 1.8228 2.7312 3.6456 4.557 9.114 14.582 1 in 400 . . 1.139 2.278 3.4177 4.557 5.695 11.392 18.228 1 in 300 . . 1.519 3.035 4.557 6.076 7.59 15.19 24.304 1 in 200 . . 2.2785 4.557 6.8355 9.114 11.39 22.785 36.456 1 in 100 . . 4.557 9.114 13.671 18.228 22.785 45.57 72.912 1 in 50 . . . 9.114 18.228 27.342 36.456 45.57 91.14 145.824 1 in 25 . . . 18.228 36.456 54.684 72.912 91.14 3182.28 291.648 1 in 10 . . . 45.570 91.140 136.710 182.280 227.85 455.70 729.120 1 in 5 . . . 91.14 182.28 273.42 364.56 455.7 911.4 1458.24

The rule for finding the amount of a drug in a given percentage of solution is as follows:

Find the number of minims in stated quantity, and multiply this by the numbers indicating percentage, placing the decimal two points to the left.

Examples: I. How many grains of drug in 2 fluid ounces of a 2 per cent.

tincture (solution) ? Two fluid ounces = 960

X (2 p. c.) = 19.20 grains.

2. How many grains of a drug in 100 C.C. of a 4 (p. c.) tincture (solution)? 100 C.C. X 16.23 = 1623.00

X 4 (p. c.) = 64.92 grains.