INTESTINAL DIGESTION. 429 



position ; for, even after a few hours' exposure to the air, it gives off a decidedly 

 putrid odor. Like ptyalin, this peculiar constituent of the pancreatic fluid 

 possesses the power (though in a less degree) of converting starch into sugar ; 

 there can be no doubt, therefore, that it is subservient to the continued diges- 

 tion of the farinaceous part of the food, during its passage through the small 

 intestines. It shares this office, however, with the " succus enterieus," which 

 has been shown by Frerichs and Hiibbenet to be also possessed of this convert- 

 ing power. It has recently been affirmed by M. Cl. Bernard, and strong evi- 

 dence has been adduced by him in support of his statement, that the essential 

 purpose of the pancreatic fluid is to promote the absorption of fatty matters, 

 by reducing them to the state of an emulsion, which is capable of finding its 

 way into the lacteals. 1 That this fluid possesses the emulsifying power in a 

 peculiar degree, may be considered as having been fully demonstrated by his 

 experiments; for on mixing it with oil, butter, or any variety of fat, at a tem- 

 perature sufficiently high to render the fatty substance liquid, and then stirring 

 the mixture for a few minutes, an emulsion is produced bearing a strong resem- 

 blance to chyle. This emulsion does not cease to present its peculiar aspect, 

 although left standing for some time; whereas although bile, saliva, gastric 

 juice, blood- serum, and other animal fluids, have a certain emulsifying power, 

 yet after a short time the oil-particles run together again, almost as if they had 

 been merely shaken up with water. Further, it is asserted by Bernard, that in 

 the Rabbit (in which the pancreatic duct discharges itself some inches lower 

 down in the intestine than does the bile-duct), when fatty matters have been 

 introduced into the alimentary canal, they undergo no considerable change, until 

 they have passed the orifice of the pancreatic duct ; an oily emulsion being then 

 for the first time found in the intestinal canal ; and the contents of those absorb- 

 ents only having the opaque whiteness of chyle, which originate in the intes- 

 tinal villi below that orifice. So, again, M. Bernard affirms that by putting a 

 ligature round the pancreatic duct, the digestion of oleaginous matter is so com- 

 pletely prevented, that it is found unchanged in the lower part of the intestinal 

 tube, and no opalescent chyle is found in the lacteals. This position is further 

 strengthened by the fact ascertained by clinical observation, 2 that there is a close 

 relation between disease of the pancreas, and the discharge of fatty matters per 

 anum ( 198). It has been shown, however, by the experimental researches of 

 Frerichs, Lehmann, Lenz, 3 and others, that the statements of M. Bernard are 

 too exclusive in their character; for that the digestion and absorption of fatty 

 matters will take place after the pancreatic duct has been tied (sufficient time 

 having been given for the evacuation of any pancreatic fluid which may have been 

 in the alimentary canal previously to the operation), and even in the lower part 

 of the small intestine, into which these substances have been conveyed by in- 

 jection, after it has been completely separated by a ligature from the upper part 

 into which the pancreatic fluid has been poured. It further appears from their 

 experiments, that a mixture of the pancreatic fluid with bile and the " succus 



1 "Archiv. Gener. de Med.," torn. xix. It lias been assumed by Frerichs, Lenz, and 

 other objectors to M. Bernard's views, that he maintains that the pancreatic fluid saponi- 

 fies the neutral fatty matters taken in as food, converting them into fatty acids and glyce- 

 rine whilst yet within the intestinal canal. It is no doubt true that M. Bernard considers 

 that some such transformation takes place in the body, before the fatty matter is ultimately 

 disposed of; but he constantly speaks of the emulsifying power as the peculiar attribute of 

 the pancreatic fluid, and only asserts that saponification takes place in artificial digestion, 

 when the fluid is left for some time in contact with fatty substances ; so that the Author 

 is inclined to regard the objections above alluded to, as having arisen from a misappre- 

 hension of M. Bernard's meaning. (See also Dr. Donaldson's account of M. Bernard's 

 discoveries, in the "Amer. Journ. of Med. Sci.," Oct. 1851.) 



2 See Dr. Bright's researches on this point, in " Med.-Chir. Trans.,-" vol. xviii. 

 "De Adipis Concoctione et Absorption," Dorpat, 1850. 



