172 TEXT-BOOK OF PHYSIOLOGY. 



until quite recently entirely to peristaltic movements of their muscu- 

 lature. It has been stated that with the passage of the food through 

 the isthmus of the fauces the posterior wall of the pharynx advances 

 and seizes the food, and in consequence of a rapid peristaltic move- 

 ment running through its constrictor muscles from above downward 

 is transferred to the esophagus; that with the entrance of the food 

 into the esophagus a similar peristalsis, varying in rapidity in different 

 sections in consequence of a change in the character of its muscula- 

 ture, gradually transfers the food into the stomach. There can be 

 but slight doubt that by this method the bolus of food, especially if 

 it is of firm consistence and of a size sufficient to distend the esoph- 

 agus, is transferred into the stomach, but that it is the exceptional 

 rather than the usual method has been demonstrated by Kronecker, 

 Falk, and Meltzer. 



In 1880 the first of these experimenters made the observation that 

 the sensation in the stomach following the swallowing of a mouthful 

 of cold water occurred too quickly to be explained by the prevalent 

 belief that its transference was caused by ordinary peristalsis, the rate 

 of progression of which was known to be slow. Falk then discovered 

 the fact, by introducing through the mouth into the pharynx a tube 

 connected externally with a water manometer, that during the act of 

 swallowing there is a sudden rise of pressure equal to about tw r enty 

 centimeters of water. 



These experiments demonstrated that at the beginning of degluti- 

 tion there is a sudden rise of jarpssiffl^the result of a quickly acting 

 force residenfih the mouth ofpharynx, in consequence of which the 

 food is rapidly thrown down into the stomach, peristalsis playing no 

 part in the process. The proof, however, of these statements was 

 furnished by Meltzer. This observer introduced into the pharynx 

 and esophagus rubber tubes, the ends of which were provided with 

 thin-walled rubber balloons which could be distended with air. 

 The outer ends of the tubes were connected with Marey's recording 

 tambours. Any compression of the balloon would be followed by 

 the passage of the air into the tambour and an elevation of the lever. 

 With one balloon in the pharynx and the other in the esophagus at 

 varying depths, and the recording levers of the tambours applied 

 against the surface of a revolving cylinder, it became possible, with 

 the addition of a chronogram, to obtain a graphic representation of 

 the time relations of simultaneous and successive compressions of 

 the two balloons. 



It was found as the result of many experiments that no matter 

 how deep the position of the esophageal balloon, it was compressed 

 simultaneously with the pharyngeal balloon, as shown by the rise of 

 the levers on swallowing a mouthful of water. The interval of time 

 between the rise of the two levers did not amount to more than the 



