CKIB-BITING. 



55d 



can observe during the practice of the vice, that a gulp of air 

 passes down the gullet in the direction of the stomach. 



3. Owing to the peculiar construction of the horse's stomach, 

 which, under ordinary circumstances, does not permit of vomiting, 

 we may, in the dead animal, fill the stomach with air from the 

 bowel end, without any of the air escaping into the gullet. 



4. The gas in the stomach and first part of the intestines of 

 wind-suckers, has been proved by chemical analysis to consist 

 exclusively of ordinary air. 



5. If this vice were characterised by belching, the employment 



Fig. 148. — Front view of the incisor teeth of a crib-biter, 30 years 

 old. N.B. — The_]^ tushes of j the lower jaw are in view, owing to 

 great age. 



of means that would prevent its practice would naturally be fol- 

 lowed by flatulent distension of the abdomen, which, 'however, does 

 not ensue if such preventive means be used. 



6. Gerlach and Hering have proved that the division of certain 

 swallowing muscles (sterno-liyoideus, suh-scapulo-hyoideus, and 

 sterno-'tnaxillaris) "will stop the vice for the time being. 



To me, a thoroughly satisfying proof that swallowing air and 

 not its eructation is the essential act of this vice, is the fact that 

 placing in the animal's mouth a bridle with a hollow mouthpiece 

 perforated with holes (p. 562), will prevent its practice. We can 

 easily see that the use of this contrivance, by furnishing, at each 



