ON THE NATURE AND AFFLICTIONS OF THE STOMACH.

Thesis 1.

The stomach, which the Greeks call koilia or gaster, is that part of the body which nature created for the purpose of converting food and drink into chyle.

2. This consists of two proper tunics, and those fibrous; the inner of which, shared also with the gullet and the mouth, is membranous, while the outer in a certain manner emulates flesh; from the outside another membrane surrounds it, which it received from the peritoneum.

3. Its shape is round, but compressed on both sides, wider on the left side than on the right, where it yields to the liver.

4. Its position is beneath the transverse septum [diaphragm], and it takes its beginning from the xiphoid cartilage in the middle space of the body, except that it deflects slightly toward the left. For hither its first orifice is especially turned, just as the other is more toward the right. For it has two orifices, both situated in a higher position. Its entire posterior part rests upon the spine, with which it adheres at the first lumbar vertebra.

5. Its mouth, indeed, which the ancients were accustomed to call the kardia, is fixed not to the spine, but to the diaphragm, as if hanging and suspended. Nor is it joined only to those, but to all surrounding parts by connection and sympathy: to the liver, spleen, intestines, heart, and brain, and that through the shared communion of membranes, nerves, veins, and arteries.

6. On the right side of the stomach, which has hidden and concealed itself deeply beneath the lobes of the liver, is its other orifice and the exit to the intestines. Nature fashioned this narrower in its upper part, lest any of the food which had not first been exquisitely broken down and pulverized should be able to escape.

7. The premature escape of food is hindered even more by two glandular tubercles, which stand within at the pylorus; when these apply themselves and move closer, they close the path and exit. But when the time for emitting the chyle arrives, they withdraw and are opened: not indeed by our nod and will, but by natural impulse alone.

8. The principal and primary function of the stomach is chylosis, which the Latins call the first concoction, or the concoction of the stomach.