We can readily understand why women with changes in the thyroid and sexual glands are so often attacked by gall-stone disease. In these women there is, as a rule, atony of the intestines, with habitual constipation. This intestinal atony is also accompanied by an atony of the gall-ducts, and so the bile is more or less stagnant in these ducts. As shown by Morat and Doyon,[136] the gall-ducts contract rhythmically every ten to twenty seconds, and the bile is thus expressed. The periodical compression of the liver by the diaphragm at each inspiration also helps this expression of the bile. Thus it flows under a certain pressure through the choledochus, and it is easy to understand that the billions of microbes which infest the intestines, will have great difficulty in passing the narrow and tortuous passages of the bile-ducts through which bile is circulating at great pressure. And this is of the utmost importance, for if microbes are able to pass the common duct and thus enter the bile-ducts, they will set up inflammation, as was shown by several French authors: Gombault, Charcot, Gilbert, etc. Footnote 136: Traité de Physiologie. Inflammation of the bile-ducts plays a most important part in the origin of gall-stone disease, for, as Naunyn and his pupils have shown, inflammation of the bile-ducts leads to a precipitation of cholesterin, and so to the formation of gall-stones. In women gall-stone disease is more frequent than in men. This depends upon the greater frequency of diseases of the thyroid and sexual glands in women. Changes in the sexual organs produce an irritation of the splanchnic with checking of the peristaltic movements of the intestine and, at the same time, relaxation of the muscular coat of the bile-ducts. Thus there arises a deficient expression of bile, and stagnation follows, with invariable immigration of bacilli producing inflammation and precipitation of cholesterin and gall-stones. For the above-mentioned reasons constipation is far more frequent in the female, and constipation, being always accompanied by atony of the bile-ducts with stagnation of the bile, directly exposes to the risk of gall-stone disease. In men gall-stone disease may often be considered a manifestation of old age. It appears, as a rule, after the fortieth year, and is often brought about by previous infectious diseases. In such cases obesity often develops first, and later gall-stone disease. For those who are interested in this subject we would refer to our communication[137] on the origin of gall-stone disease following changes in certain ductless glands. Considerable, sometimes enormous, loss of weight is a very frequent symptom of gall-stone disease, and is probably due to pancreatic alterations. Footnote 137: Archives générales de médecine, Octobre, 1905, and Monthly Cyclopædia of Practical Medicine, 1906.