Those internal ventilators, the lungs, and those external ducts, the pores, are constantly at work purifying the body; and they are actively assisted by the kidneys and the bladder. Observation extending over many years of practice induces me to believe that among those who suffer from chronic constipation two-thirds to three-fourths of the fecal mass is taken into the system and eliminated by the kidneys, mucous membrane, and skin. Diseases of the above organs are numerous and seemingly incurable from the fact that their common cause has not been discovered and treated properly. Were it not for these organs steadily at work, the labor of the bowels would be of little avail. But while the importance of the former cannot be ignored, it must be conceded that the most important of all the eliminating organs are the bowels, for their function is to discharge not only the waste solids but also a great amount of waste liquids and gases as well. [Illustration: Fig. 6. 9. The anus. Levator ani muscle seen on each side. 8, 8. The rectum. 7. Beginning of the rectum. 6. The sigmoid flexure. 5. The descending colon. 4. The transverse colon. 3. The cæcum, or _caput coli_. 2. Appendicula vermiformis. 1. The end of the ileum.] Undue fermentation of the ingesta (the aliment taken into the system) generates poisons of more or less virulence; it must therefore be obvious that a clean intestinal canal is necessary after every meal to further the normal digestive process. Very often the outlet of the sigmoid flexure is obstructed. Figures 6 and 7 are shown to make the cause of this obstruction more clear. In Figure 7 we see the longitudinal and transverse fibers that form the wall of the rectum. In all cases of chronic obstipation, the muscular structure of the anus, rectum, and frequently of a portion of the sigmoid flexure is invaded with chronic inflammation of a very severe and serious character. [Illustration: Fig. 7. A view of the longitudinal muscular fibers of a section of the rectum: 2, upper portion of the rectum; 3, 4, 5, the three bands of longitudinal fibers of the colon continued upon the rectum; 6, the longitudinal muscular fibers of the rectum formed by the expansion of those of the colon. A view of the muscular coat of the colon: 1, 1, one of the bands of longitudinal muscular fibers; 2,2, the circular fibers of the muscular coat.] What is the result of this inflammation? Self-evidently contraction of the muscular structure, as you would quickly enough discover were one of your hands or arms inflamed. Though constant attention should be given to the much more important organ, the rectum, practically none is given it. “Out of sight, out of mind.”