PHYSIOLOGICAL ABSORPTION. 349 



alkali of the bile and pancreatic juice, the soaps and glycerine 

 absorbed, the fatty acid again set free in the cell (the alkali 

 perhaps being- used again), and recombined with the 

 Sflvcerine to form neutral fat. 



Will fed frogs on pillules of pure palmitic acid, the melting 

 point of which is, of course, far above the body temperature 

 of the animal, and found distinct fat globules in the cells of 

 the gut. He states that he controlled the results with ob- 

 servations on the appearances in the gut of starved frogs ; 

 a necessary precaution, since it has been shown by Griin- 

 hagen that the gut cells of starving winter frogs are loaded 

 with fine fat grains, though the appearance is a very differ- 

 ent one to that seen in a frog fed with fat. Ewald, too, 

 kept exsected gut mucosa at body temperature in a solu- 

 tion containing soap and glycerine, and also maintains that 

 he got evidence of fat grains in the cells. 



Altmann has suggested a solution of the free fatty acids 

 in the bile salts, a fact demonstrated to be possible by 

 Strecker and Latschnikoff, and naturally maintains that 

 his " granula " are the active agents in the regeneration 

 that follows absorption. 



Now, we know from the work of Immanuel Munk not 

 only that considerable amounts of fatty acid can be detected 

 in the gut of a dog at any time during the digestion of a 

 meal of the neutral glyceride, but also that animals may be 

 nourished upon fatty acids as well as on fats, provided an 

 equivalent amount is supplied ; and further, that the fatty 

 acids given by the mouth appear in the chyle to a large 

 extent, though not exclusively, in the form of neutral fats. 



A few years back, a lucky case of chylous fistula in a 

 patient enabled Munk to demonstrate upon man the truth 

 of these assertions. In this case, practically the whole chyle 

 flowed at intervals from the fistula. Olive oil by the 

 mouth was collected as such at the fistula, mutton fat gave 

 a chyle fat solid at the temperature of the room ; but erucic 

 acid from rape-seed oil gave the neutral fat erucin. 



But the most elegant experiment was with spermaceti. 

 This has a melting point of 53 c, and is a compound of 

 palmitic acid and cetyl-alcohol ; 14 per cent, of the weight 



25 



