200 DIGESTION. [CHAP. xxiv. 



this effect, nothing more is necessary than to compare the inner sur- 

 face of the great end of the stomach with any other part of its inner 

 surface : the sound portions will appear soft, spongy, and granulated, 

 and without distinct blood-vessels, opaque and thick ; while the 

 others will appear smooth, thin, and more transparent, and the 

 vessels will be seen ramifying in its substance ; and upon squeezing 

 the blood which they contain from the larger branches to the smaller 

 it will be found to pass out at the digested ends of the vessels, and 

 to appear like drops on the inner surface."* 



Hunter remarked, that solution of the stomach is very commonly 

 found in fishes, which almost always die a violent death, and fre- 

 quently during digestion.f 



Dr. Carswell investigated this subject, and obtained results con- 

 firmatory of the views of John Hunter. He killed rabbits and dogs 

 during the digestive process, allowing them to lie for various periods 

 after death. If examined four hours after death, he found that the 

 solution had affected the mucous, submucous, and muscular tunics : 

 when six hours had elapsed, the peritoneal coat was found softened, 

 in addition to the others; the stomach was consequently perforated, 

 and the food passed through the opening and came in contact with 

 the liver, spleen, diaphragm, and intestines, one or all of which ex- 

 hibited the same kind of softening as that found in the stomach, 

 at those places where the digested food touched the parts. In 

 another series of experiments, where the animals were suffered to 

 lie for a still longer period after being killed, perforation of the 

 diaphragm or oesophagus had taken place, and the liquid part of 

 the food had flowed into the cavity of the chest, causing digestion 

 and softening of the pleura and of the lungs. J 



3. The Gastric Juice. From these various sources we derive the 

 most ample evidence of the existence of a fluid secreted by the 

 walls of the stomach during digestion, capable of exerting a reduc- 

 ing or solvent influence upon food. This fluid is the gastric juice 

 the succus gastricus. 



It is of great importance to a correct theory of digestion to de- 

 termine the precise composition of this fluid. Dr. Prout, in this 

 country, in 1823, two years prior to the commencement of Beau- 

 mont's experiments, had determined the existence of an acid fluid 

 secreted during digestion, and had analysed it in the rabbit, hare, 



* Hunter's Animal (Economy, Owen's edition, p. 119. 



t Spallanzani confirmed Hunter's statements. 



Ed. Med. and Surg. Journal, vol. xxxiv. p. 262. See also an excellent deli- 

 neation of this post mortem condition by Dr. Carswell, in his " Illustrations of 

 the Elementary Forms of Disease," art. Softening. 



