94 
I think, however, that no one can have a doubt about the 
want of care which is shown generally in dispensing, by the 
above table. A large percentage have dispensed within a 
range of accuracy which many might consider reasonable. 
I have, however, made all my estimations with analytical 
accuracy, and I think it must be left to the medical profession 
to decide what limits of error they consider might be allowed. 
With the view to decide what amount of inaccuracy a phar- 
macist would consider allowable, I consulted a gentleman 
who is a partner in an establishment which does a con- 
siderable business in dispensing. After informing him of the 
investigation I had been making, I asked him what 
amount of inaccuracy he would consider allowable in 
dispensing 120 grains of potassium iodide in 6 ounces of 
fluid, and also for 40 grains of zinc sulphate in 2 ounces 
of fluid; he considered that in both cases they ought to 
be absolutely accurate, but if I allowed three-tenths of a 
grain either way I should be allowing sufficient for all 
practical purposes. I have, however, been still more lenient 
than my pharmaceutical friend, and have allowed five- 
tenths of a grain on either side of the prescribed quantity 
as the range of practical accuracy. I know that many 
dispensers will take objection to this range of inaccuracy as 
impracticable. We, as analysts, can weigh easily to the 
one-hundredth part of a grain, and I know that balances used 
by dispensers for weighing such quantities as 120 grains 
are capable of turning with the tenth part of a grain if kept 
in good condition, and I think under such circumstances it 
would be absurd for any one to contend that it is impracti- 
cable to weigh drugs within half a grain on these premises. 
I have formed the following summaries of the above re- 
sults:— For the potassium iodide mixture, two druggists out 
of the eighty-one have given the exact weight prescribed ; 
nine out of the eighty-one have come within the practical 
