The active principles of internal secretions have been termed “hormones”—from ὁρμάω, I announce. The glands of the pyloric mucous membrane secrete a hormone which calls upon the rest of the membrane to pour out gastric juice (_cf._ p. 89). What induces the cells of the pyloric mucous membrane to produce the gastric hormone? Their activity in this respect evidently depends upon the presence in the stomach of partially digested proteid substances. The cells judge, as it were, when these substances come into contact with them, that there is more work for the great bag of the stomach to do. They call upon the part which is most active in secreting gastric juice to pour it out quickly and get the business of digestion over. Meat-extracts, which contain the products of protein disintegration, have a similar influence in promoting the formation of the hormone. Hence, no doubt, the general custom, found from experience to be beneficial, of commencing dinner with soup; although it must be remembered that the rapid absorption of meat-extracts makes them peculiarly valuable as restoratives. They afford very little energy, but what they have to give is quickly placed at the disposal of the economy. Persons whose stomachs are unduly irritable are advised to avoid soup. It leads to undesirable activity on the part of the gastric glands, and especially of the acid-secreting cells. Well chewed bread also encourages the production of the hormone. Here it may be well to call attention to the evident division of the stomach into two parts—the large bag, or cardiac portion, which hangs down; and the smaller, funnel-shaped pyloric end, which is almost vertical. The distinction between these two parts is faintly visible in the resting stomach, but even opening the abdomen tends to obliterate it. That it is much more evident during active digestion has been shown by adding subnitrate of bismuth to the food, and throwing the shadow of the stomach on a screen with Röntgen rays. When this is done, it is seen that the two parts work in different ways. Food is churned round and round in the cardiac portion, and pressed towards the pylorus. Its fluid products, mixed with the abundant secretion of the gastric mucous membrane, are wrung out of it by the pyloric funnel. They are squeezed towards the pylorus, which opens at intervals to let them through. If lumps of solid matter reach it, the pyloric valve closes tightly, until the undigested food has fallen back into the dependent bag. Dyspeptics are sometimes unpleasantly conscious of the contractions of the pyloric funnel. In fact, putting aside pain due to gastritis, all the discomfort of dyspepsia is felt on the right side. Flatus accumulates beneath the pyloric valve. The valve will not open to let it pass. The pyloric portion of the stomach contracts strongly. Notwithstanding the general trend of movement in the opposite direction, the gases are squeezed back into the larger bag, and escape through the cardiac orifice.