CHYMIFICATION. 583 



from physiologists than any of the others that have been mentioned, and 

 may be regarded as established. According to that observer, chymifi- 

 cation is owing to the solvent action of a fluid, secreted by the stomach, 

 which accumulates in that viscus between meals and during hunger, 1 

 and acts as a true menstruum on the substances exposed to it. This 

 fluid, to which he gave the name gastric juice, he affirmed to be 

 peculiar in each animal, according to its kind of alimentation, corre- 

 sponding, as regards its energy, with the rest of the digestive apparatus, 

 and differing in its source in the series of animals ; in some, proceed- 

 ing from the follicles of the oesophagus; in others from those of the sto- 

 mach ; but always identical in the same animal ; generally transparent, 

 yellowish; of a saline taste; bitter; slightly volatile; and stronger in 

 animals with a membranous than in those with a muscular stomach, and 

 than in ruminant animals. To obtain the juice, Spallanzani opened 

 animals, after they had been made to fast for a time ; and collected the 

 juice that had accumulated in their stomachs ; or he made them swallow 

 tubes pierced with holes, and filled with small sponges. By withdraw- 

 ing these tubes, by means of a thread attached to them and suffered to 

 hang out of the mouth, and expressing the sponges, he obtained the 

 fluid in quantity sufficient for examination. To determine whether this 

 fluid, obtained from fasting animals, was destined to chymify the food, 

 he tried the following experiments. He caused numerous animals to 

 swallow tubes filled with food, but pierced with holes, so that the juices 

 of the stomach might be able to get into their interior; and found that 

 chymification was effected, when he had taken the precaution to chew 

 the substances before they were put into the tubes, or to triturate them ; 

 and the process was always more readily accomplished, the more easy 

 the access of the fluids. On repeating these experiments on animals 

 of various kinds, with a muscular or membranous, and musculo-mem- 

 branous stomach ; on pullets, turkeys, ducks, pigeons, rooks, frogs, sala- 

 manders, eels, serpents, sheep, cats, &c., he obtained the same results; 

 and hence he affirmed, that trituration cannot be the essence of chymi- 

 fication. Reaumur, 2 originally a believer in the doctrine of tritura- 

 tion, had previously arrived at the same conclusion, by experiments 

 of a similar kind. Spallanzani next repeated those experiments upon 

 himself. Having well chewed different articles of food, he enclosed 

 them in wooden tubes pierced with holes, and swallowed them ; but, as 

 the tubes caused pain in the bowels, he substituted small bags of linen. 

 The substances contained in bags were digested without the bags being 

 torn; a fact, which proved, that digestion must have been accomplished 

 by means of a fluid, that penetrated them. In 1777, Dr. Stevens 3 re- 

 peated these experiments. He made a person swallow balls of metal, 

 filled with masticated food, and pierced with holes : when the balls were 

 voided, thirty-six or forty-eight hours afterwards, they were entirely 

 empty. Lastly. Spallanzani was desirous of seeing whether this solvent 

 juice could effect digestion out of the body. He put some well-masti- 

 cated food in small glass tubes, and mixed gastric juice with it. These 



1 It has been already stated, that the experiments of Dr. Beaumont have satisfactorily 

 proved that no such accumulation takes place during hunger. 



2 Memoir, de 1'Acad. pour 1752. 3 De Alimentorum Concoctione, 24. 



