ON THE ADULTERATION OF DRUGS. 
127 
country judge of its value. In medical practice we hear 
constant complaints of the disappointments experienced in 
using opium and its galenical preparations, owing to the 
varieties produced in their action hy peculiarities of constitu- 
tion, or by the state of the patient at the time; and it would 
be the height of folly to deny the influence of these disturbing 
causes. But we likewise know that varieties equal in degree 
and the same in kind may be occasioned by varieties in dose. 
I have sometimes traced to this source unpleasant effects which 
were at first believed to depend on idiosyncrasy. May it 
not, then, be worth while to inquire whether the irregulari- 
ties, apparently depending on the constitutional or incidental 
state of the patient, do not originate, more frequently than is 
at present thought, in mere differences of dose? — seeing that 
the drug must be often administered to different individuals, 
and to the same individuals in different circumstances, in 
doses of which one may be twice as great as another. 
9. To these instances of the adulteration of drugs, in the 
state in which they are supplied to the retail druggist, it might 
be well to append parallel examples of the same practice in 
the case of the galenical preparations of the Materia Medica, 
which are usually made by the retailer himself. Many adul- 
terations of this nature have come under my notice; but it 
has not been in my power to examine them with much 
accuracy, because>onthe one hand, the processes for the purpose 
are often tedious and sometimes unsatisfactory, while, on the 
other hand, some adulterations can scarcely be brought at all 
under the cognizance of chemical analysis. I shall, therefore, 
be satisfied with mentioning one only, which I have carefully 
examined, out of a list which, with more leisure, would easily 
furnish many similar illustrations. This is laudanum; 
which, as may be inferred from what has just been said, is 
liable to vary in consequence of varieties in the crude drug 
employed in preparing it, but which the following facts will 
show to vary to a degree which cannot be ascribed to that 
circumstance alone. Laudanum, which I prepared from first 
