302 THE POPULAR SCIENCE MONTHLY 



his observation of the phenomenon. 37 Six years ago Boldireff demon- 

 strated that the whole gastro-intestinal tract has a periodic activity- 

 while not digesting. 38 Each period of activity lasts from 20 to 30 

 minutes, and is characterized in the stomach by rhythmic contractions 

 10 to 20 in number. These contractions, Boldireff reports, may be 

 stronger than during digestion, and his published records clearly sup- 

 port this statement. The intervals of repose between periodic recur- 

 rences of the contractions lasted from one and a half to two and a half 

 hours. Especially noteworthy is Boldireff's observation that if fasting 

 is continued for two or three days, the groups of contractions appear 

 at gradually longer intervals and last for gradually shorter periods, 

 and thereupon, as the gastric glands begin continuous secretion, all 

 movements cease. 



Observations Suggesting a Relation Between Contractions and 

 Hunger. — When Boldireff's paper was published I was studying auscul- 

 tation of abdominal sounds. Eepeatedly there was occasion to note that 

 the sensation of hunger was, as already stated, not constant, but recur- 

 rent, and that its momentary disappearance was often associated with 

 a rather loud gurgling sound, as heard through the stethoscope. That 

 contractions of the alimentary canal on a gaseous content might ex- 

 plain the hunger pangs seemed probable at that time, especially in the 

 light of Boldireff's observations. Indeed, Boldireff himself had con- 

 sidered hunger in relation to the activities he described, but solely with 

 the idea that hunger might provoke them; and since the activities 

 dwindled in force and frequency as time passed, whereas, in his belief 

 they should have become more pronounced, he abandoned the notion of 

 any relation between the phenomena. 39 Did not Boldireff misinterpret 

 his own observations ? When he was considering whether hunger might 

 cause the contractions, did he not overlook the possibility that the con- 

 tractions might cause hunger? A number of experiences have led to 

 the conviction that Boldireff did, indeed, fail to perceive part of the 

 significance of his results. For example, I have noticed the disappearance 

 of a hunger pang as gas was heard gurgling upward through the cardia. 

 That the gas was rising rather than being forced downward was proved 

 by its regurgitation immediately after the sound was heard. In all 

 probability the pressure that forced the gas from the stomach was the 

 cause of the preceding sensation of hunger. Again the sensation can 

 be momentarily abolished a few seconds after swallowing a small ac- 

 cumulation of saliva or a teaspoonful of water. If the stomach is in 

 strong contraction in hunger, this result can be accounted for as due to 

 the inhibition of the contraction by swallowing. 40 Thus also could be 



87 His, Archiv fiir Anatomie, 1903, p. 345. 



88 Boldireff, loc. cit., p. 1. 

 88 Boldireff, loc. cit., p. 96. 



40 See Cannon and Lieb, American Journal of Physiology, 1911, XXIX., 

 p. 267. 



