RUMINATION AND EEGHRGITATION. 295 



sage of a new bolus to the mouth for rumination ; the inter- 

 val of time being very short, only from four to five seconds. 1 

 There is considerable difference in the length of time em- ' 

 ployed by different animals in rumination. In the ox, about 

 one-quarter of the day is thus occupied ; but in the sheep 

 and the goat the process is much more rapid. 2 



Additional interest is attached to the function of rumi- 

 nation in the inferior -animals, in connection with human 

 physiology, from the fact that an analogous process has 

 sometimes been observed in the human subject ; though it is 

 rare and generally connected with a pathological condition. 

 Such cases have been often quoted, and, in the earlier works 

 on physiology, were frequently exaggerated ; but a few in- 

 stances, well authenticated, are on record in which rumina- 

 tion had become habitual. A very remarkable case of this 

 kind is reported by Home. The subject was an idiot-boy, aged 

 nineteen years, who had an appetite so ravenous that it be- 

 came necessary to restrict the quantity of food. At dinner he 

 ordinarily ate about a pound and a half of meat and vegeta- 

 bles, swallowing the whole in two minutes. He began to chew 

 the cud at the end of a quarter of an hour. The muscles of 

 the throat could be seen to contract when the bolus was 

 passed back to the mouth. He chewed the food by two or 

 three movements of the jaws and then swallowed it again. 

 This was repeated at intervals for half an hour, during which 

 time he was always more quiet than usual. The intellect 

 was so feeble that it was impossible to ascertain whether the 

 rumination was voluntary or involuntary. 3 One of the cases 

 of rumination most frequently referred to is that of M. 

 Cambay, who studied the phenomena in his own person, and 



1 COLIN, Traite de Physiologic Comparee des Animaux Domestiques, Paris, 

 1854, tome i., p. 527. 



2 COLIN, op. cit., p. 521. 



3 HOME, Observations on the Structure of the Stomachs of Different Animals, 

 with a view to elucidate the Process of converting Animal and Vegetable Substances 

 into Chyle. Philosophical Transactions, London, 1807, p. 174. 



