The case of Mr. W. was a pretty apt illustration of the truth of what I regard as the great or cardinal doctrine of temperance, faintly announced in Chapters XVIII., XXI., XXVIII, and elsewhere, viz., that, as a general rule, much more mischief is done to society at large by the frequent or at least habitual use of small quantities of poison, than by an equal aggregate quantity in much larger doses. I mean just this: The poisonous effects of Mr. W.'s coffee, though the amount daily taken was trifling, produced a greater aggregate of mischief, in the end, than if the same amount of poison had been applied in a very short time. A pint of rum drank in a single day will do much less mischief to the human constitution, than if divided into twenty _small_ doses and two of them are taken every day for ten days. In the first case the effect will be severe, but temporary; in the second, it will seem to be trifling, but there will be an accumulation of ill effects, a heaping up, as it were, of combustible matter in the system, till by and by when an igniting spark comes to be applied to the pile, lo! we have an explosion. Some of the hydropathists who knew the facts concerning Mr. W.,--for the case did not occur in a corner,--tried to make it appear, perhaps in all honesty, that he was cured by the cold _douche_. Now I have no disposition to deny, wholly, its good effects. I have given you the facts just as they were. Yet I have not a doubt that had he returned to his coffee, the same troubles or others of equal magnitude would have fallen to his lot again, despite the influences of the _douche_. In truth, I know of no sensible hydropathist who, in such a case, would rely upon the _douche_ alone; which is to concede, practically, all that I desire to claim. CHAPTER LIV. THE OPIUM PILL BOX. The statements of the following chapter will include a confession of one of the principal faults of my life,--a fault, moreover, which, as a physician, I ought to have guarded against with the most assiduous and unwearied care. For no man more than the medical man, is bound to let his light shine--especially in the matter of general temperance, in such a manner that others may be benefited by it.