Page:Popular Science Monthly Volume 81.djvu/311

From Wikisource
Jump to navigation Jump to search
This page has been proofread, but needs to be validated.

festing periodic contractions, the intestines also are active. Conceivably all parts of the alimentary canal composed of smooth muscle share

PSM V81 D311 Intragastric oscillations of hunger recorded by a pneumograph.png

Fig. 2. One half the original size. The same conditions as in Fig. 1. (Fifteen minutes.) There was a long wait for hunger to disappear. After x, Mr. W. reported himself "tired but not hungry." The record from y to z was the continuance on a second drum of x to y.

in these movements. The lower œsophagus in man is provided with smooth muscle. It was possible to determine whether this region in Mr. Washburn was active during hunger.

To the œsophageal tube a thin-rubber finger-cot (2 cm. in length) was attached and lowered into the stomach. The little rubber bag was,

PSM V81 D311 Oscillations of the esophagus by a pneumograph.png

Fig. 3. One half the original size. The top record represents compression of a thin rubber bag in the lower œsophagus. The pressure in the bag varied between ft and 13 cm. of water. The cylinder of the recorder was of smaller diameter than that used in the gastric records. The œsophageal contractions compressed the bag so completely that, at the summits of the large oscillations, the respirations were not registered. When the oscillations dropped to the time line, the bag was about half inflated. The middle line registers time in minutes (ten minutes). The bottom record is Mr. W.'s report of hunger pangs.

distended with air, and the tube, pinched to keep the bag inflated, was gently withdrawn until resistance was felt. The air was now released from the bag, and the tube further withdrawn about 3 cm. The bag was again distended with air at a manometric pressure of 10 cm. of water. Inspiration now caused the writing lever, which recorded the pressure changes, to rise; and a slightly further withdrawal of the tube changed the rise, on inspiration, to a fall. The former position of the tube, therefore, was above the gastric cavity and below the diaphragm. In this position the bag, attached to a float-recorder (with chamber