106 



PHYSIOLOGY OF THE PANCREAS. 



sanguinis — with which all the vascular tissues are saturated j it cannot enter their 

 pores, and consequently cannot be absorbed. 



" 2. Liquid fats, when emulsified by albumen, are reduced to minute particles, 

 each coated with albumen. In this state they are miscible with the liquor sanguinis, 

 moistening the tissues, can enter their pores, and are then capable of absorption. 

 This is the sole condition requisite for the absorption of fats. 



" 3. The white milk-like fluid, named chyle, is this emulsion of the fatty mat- 

 ters of the food, mixed with the ordinary lymph, always contained in the lymphatics 

 of the alimentary canal, and other abdominal organs and mesentery. The mole- 

 cular base of Gully is the microscopic appearance in the chyle, of the minute globules 

 of fat coated with albumen. 



"4. Albumen forms a perfect and persistent emulsion with oils. The pancreatic 

 fluid is a saturated albuminous solution, and forms with oils an emulsion equally as 

 perfect and permanent as that of albumen. 



" 5. Tlie pancreatic juice is the only highly albuminous fluid in the alimentiiry 

 canal, and can accomplish the formation of a perfect emulsion ; and the opinion of 

 M. CI. Bernard, that this process is one of its functions, is, it appears to me, 

 sustained. 



" 6. The observations of M. CI. Bernard, that the formation of the emulsion of 

 fats in rabbits is at and below the pancreatic duct, and not above it, is confirmed 

 by the experiments reported in this communication. And further, that the experi- 

 ments on rabbits are the most reliable, as being a true exemplification of the natural 

 process, unattended with violence and torture to the animals, more or less disturbing 

 in their effects. 



" 7. That M. CI. Bernard's view of the decomposition of fats by the pancreatic 

 juice is not proved, is opposed by the nature of the process, and by analogy with 

 other emulsions; it is unnecessary to the accomplishment of the absorption of fats, 

 and introduces other and complicated processes, that are unknown to exist, and are 

 mere hypotheses." 



Whilst engaged, last summer, in the investigation of the physical and chemical 

 constitution of the fluids and the comparative anatomy and physiology of cold- 

 blooded animals, it occurred to me that the pancreas of carnivorous animals should 

 be larger than that of the frugivorous or granivorous animals, because it is much 

 more incessantly exercised in the secretion of a fluid for the emulsifying of fats. 

 Accordingly, I ascertained accurately the weights of the body and pancreas of every 

 animal that came into my possession. Dividing the weight of the former by that 

 of the latter, we obtain the weight of the pancreas in relation to that of the body, 

 and the relative size of this organ in different animals is thus ascertained. 



The weights of the animals were obtained with a pair of scales capable of turning 

 to half a grain, and the weights of the organs with a delicate balance, capable of 

 turning to j-^-^th of a grain. The following table exhibits the most important 

 results thus found. 



