It is popularly supposed that the drug passes from the stomach into the small intestines, rendering their contents more liquid; then passes into the colon, producing the same effect upon its more solid contents, thus causing an evacuation. Many people have no conception, whatever, of the _modus operandi_ of a purgative drug, simply believing that it acts in a certain mysterious manner, but the above described process is generally believed to be the correct one by those who have thought upon the matter, but lack physiological knowledge. It is a huge mistake. Any purgative drug, whether aperient, laxative or cathartic, is dissolved in the stomach by the action of the gastric juice--in fact, goes through the same digestive process as the food that is eaten, that is, it passes into the small intestines and is there absorbed into the circulation. By its irritation of the nerves, the secretory and excretory processes of the system are stimulated into abnormal action, and an extra quantity of fluid is poured into the colon to dissolve the accumulated mass; which is about as scientific a proceeding as pouring a quart of water into a washbowl on the upper floor of a dwelling to clear away an obstruction in the main drain of the building. And, again, as previously stated, the action of laxatives and cathartics, especially the variety known as hydrogo-cathartics (watery), fill the ano-rectal cavity and the loculi, or folds of the colon, with a foul watery solution that is a perpetual source of irritation to the sensitive mucous surface, hastening and intensifying the process of auto-infection by absorption, that is constantly going on. And what about the enormous drain upon the vital forces? Who is not familiar with the feeling of exhaustion when the reaction sets in after the employment of such methods of relief? How can it be otherwise? These stimulants to defecation are like the applications of the whip to the jaded horse--they excite the system to make a supreme effort in the required direction, but the reaction is disastrous in the extreme. With the repeated demands upon the delicate nervous system incidental to constant catharsis is it any wonder that we are so constantly confronted with cases of nervous collapse? The wonder would be if it were otherwise. Nor are these the only objections to be urged against purgative medication. Its effects upon the digestive functions is, in the highest degree, destructive. It would be next to impossible to find an individual addicted to the use of cathartics whose digestion was not, practically, a wreck. It is true, that a large part of the digestive disturbance in such cases is due to the obstructed condition of the colon, and the consequent undue retention of food in the stomach, until fermentation sets in; but no inconsiderable share of the trouble is due to the action of the drugs, by repeated over-stimulation of the nervous system, and perpetual irritation of the delicate absorbent vessels.