438 Messrs. B. Moore and D. P. Rockwood. On the 



** On the Condition in which Fats are absorbed from the 

 Intestine." By B. MOORE and D. P. ROCKWOOD. Commu- 

 nicated by Professor E. A. SCHAFER, F.R.S. Received 

 December 24, 1896, Read February 4, 1897. 



(From the Physiological Laboratory of University College, London.) 



In 1858 Dr. W. Marcel* announced to this Society the discovery 

 that bile possesses the remarkable property of dissolving to a clear 

 solution large amounts of fatty acids, and mixtures of these, when 

 heated above their melting points, and that, on cooling, these bodies 

 are again thrown out as a fine precipitate or emulsion. 



We have repeated these experiments, and are able to confirm the 

 accuracy of Marcet's observation. Thus we found that 6 c.c. of dog's 

 bile at 62 C. dissolved completely 1'5 grams of the mixed fatty 

 acidsf of beef suet, and similar solubilities were found in other 

 -cases. 



No other observations than these have, so far as we are aware, 

 been made on the effect of temperature on the solubility of fatty 

 acids in bile ; although different writers have mentioned that fatty 

 acids are soluble in bile, no measurements have been made of the 

 extent of their solubility. AltmarinJ has recently surmised that 

 fats are absorbed from the intestine as fatty acids, dissolved in the 

 intestine by the agency of the bile, but has made no quantitative 

 experiments on the solubilities of the fatty acids in bile. The for- 

 gotten experiments of Marcet, mentioned above, led us to think that 

 the fatty acids might possess, at tine temperature of the body, a fair 

 amount of solubility in bile, and as the solubility at this temperature 

 is that of most physiological interest, we have made a. series of deter- 

 minations of the solubilities of oleic, palmitic, and stearic acids, and 

 of natural mixtures of these in the proportions in which they occur 

 in lard, beef suet, and mutton suet, in the bile of the ox, pig, and 

 dog. 



Different methods were used in the determination of these solu- 

 bilities : 



1. To a measured amount of the bile under experiment, kept at a 

 temperature of 39 C., small weighed quantities of the fatty acid 

 ainder experiment were added, until no more dissolved. 



2. A quantity of bile was saturated at 39 C., with excess of the 

 fatty acid, and filtered from the excess of undissolved acid through a 



* ' Eoy. Soc. Proc.,' 1858, vol. 9, p. 306. 



f Throughout this communication the expression " fatty acids " means the fatty 

 acids present in fats, oleic, palmitic, and stearic acids. 



I 'Arch. f. Anat. u. Physiol.,' 1889, Anat-.-Abth., Suppl. Band, p. 86. 



