Smell is perhaps the most acute sense with which the equine race are endowed; the horse can appreciate that in which the human being vainly endeavors to detect even the slightest odor. Not only is the scent far more acute than that of man, but the two beings have to be compared as regards their habits; the animal is most cleanly in its tastes. Flesh it abhors, and all fatty substance it shrinks from; men eat such things with appetite. Then, the human subject can dwell, and even labor, in a tainted atmosphere with comparative impunity. A quadruped may be forced to toil in such a place; but those who oblige the creature to do this kind of work know the certain consequences of the act. They buy cheap and old horses--animals which have suffered much, and have but a year or two longer to exist. Were younger or dearer quadrupeds purchased, in which an energetic constitution would render disease more malignant, and were such animals obliged to breathe such contamination, the loss in every way would be fearful. There is, at present, a great fuss made about sanitary laws; but the attention of those to whom such subjects are confided seems to be engrossed by man and his excretions. No one yet appears to have imagined that the subject involves life in all its varieties; the horse cannot exist in the air which human lungs have exhausted; man cannot live in the atmosphere in which the horse has perished. The two creatures are not, therefore, entirely distinct; but the open nostrils and huge lungs of one horse can consume the oxygen which would support many men. Then, the dung of the horse, which is always exposed, gives off fumes only slightly less dangerous than those which emanate from the human body. Yet officers pry into alleys and into courts; they enter the habitations of the poor, and count the number of those who _sleep_ in each room. The impacted people are pointed to as the source of certain diseases, and society shudders as the medical report is circulated. No one, however, visits the stable; no one inquires whether horses _live_ in the space which affords sufficient atmosphere to support existence; no one has yet traced disease in man as probably originating in the close and contaminated fumes of nearly every London mews. Still, if the over-crowded rooms of the poor merit an elaborate report as so very dangerous to society, may not the stifling and reeking condition of the stables deserve a passing comment in its relation to the same effect?