256 DIGESTION. 



be ascertained from tlie sensations during the act, the regurgitation of food was effected 

 by persistent contractions of the muscular walls of the stomach, assisted by a slight and 

 almost involuntary contraction of the abdominal muscles and diaphragm. It is stated by 

 Cambay that, in his case, the taste of the articles of food was not modified, " but that it 

 is with something of a sense of pleasure that the ruminator thus causes to return to the 

 mouth the aliments that he has taken into the stomach, which makes them undergo a 

 new trituration." 



Rumination in the human subject is not a physiological act. It is evident that the sub- 

 stances returned to the mouth are not usually impregnated with the gastric juice, for they 

 have not the disagreeable acid taste of ordinary vomited matters. The acts are generally 

 preceded by a sense of fulness in the stomach, and their mechanism is probably nearly 

 the same as that of the regurgitation of small quantities of milk from the distended 

 stomachs of young children, which is so common. In the person of Cambay, the first 

 act was said to be voluntary, but succeeding ones were not under the control of the will. 

 Undoubtedly, the faculty of regurgitating the food may be improved by practice, and 

 we have known of an instance in which it was apparently cultivated as an accom- 

 plishment. 



The mechanism of regurgitation of portions of the contents of the stomach, aside 

 from instances simulating rumination, has been so often alluded to that it demands in this 

 connection but a passing mention. In some persons, this act may be accomplished by a 

 voluntary muscular effort, especially when the stomach is overloaded. It occasionally 

 happens, when the stomach is somewhat distended, that a small portion of its contents 

 suddenly finds its way to the mouth without even the consciousness of the individual. 

 The muscular contraction which produces this slight regurgitation is so insignificant that 

 there must necessarily have been some relaxation at the cardiac opening of the stomach, 

 which under ordinary conditions is, as we know, firmly closed. The act is then produced, 

 in part by a slight contraction of the abdominal muscles and diaphragm, and in part by 

 contractions of the stomach itself and anti-peristaltic movements of the oesophagus. It 

 has nothing of the violent, expulsive character of true vomiting, which is produced by 

 the spasmodic and involuntary contraction of the abdominal muscles and diaphragm, the 

 stomach being passive. 



The discharge of gases from the oesophagus by the mouth, accompanied with a pe- 

 culiar and characteristic sound, is very common. This is usually accomplished without 

 any marked contraction of the muscles concerned in vomiting and evidently requires very 

 little force. Usually, the cardia is so effectually closed as to prevent the passage even of 

 gases ; and, in eructation, there must be a temporary relaxation of this opening. When 

 thus relaxed, the act is accomplished chiefly by contractions of the stomach and oesopha- 

 gus. It is generally accompanied or preceded by sensible convulsive movements of the 

 oesophagus, involving, possibly, contractions of its longitudinal fibres, which would favor 

 relaxation of the cardiac opening. Although it is usually involuntary, this act is some- 

 times under the control of the will. When it occurs, while it is difficult or impossible to 

 prevent the discharge of the gas, the accompanying sound may be readily suppressed. 

 Eructation is frequently a matter of habit, which in many persons becomes so developed 

 by practice that the act may be performed voluntarily at any time. 



