442 Prof. Ramsay and Mr. Travers. The Gaseous 



amount of alkali required in the intestine for the absorption of all 

 the fats of a fattj meal, as soaps, is out of all proportion to the 

 amount actually present, being about twice the total alkalinity of the 

 body.* The first objection has already been discussed ; it has been 

 shown that the acid reaction is due to weak organic acids, and that 

 an alkaline reaction can be obtained by the use of a proper indicator, 

 due to a compound of these weak acids with bases ; in other words, 

 to soaps. 



The second objection may be met by the supposition that the same 

 quantity of alkali acts cyclically as a carrier in conveying quantity 

 after quantity of fatty radicle, as soap, from the intestine. The 

 soaps are, it is known, broken up in the intestinal cells, and formed 

 into fats by the action of the cell ; in such a reaction alkali is set free, 

 and there is no obvious reason why it should not be returned to the 

 intestine and serve to carry a fresh portion of fatty radicle dissolved 

 as soap into the epithelial cells. Such an action takes place in the 

 acid secreting cell of the gastric gland, where sodium chloride is 

 taken up from the blood, split into acid and alkali, and the alkali 

 returned to the blood while the acid passes into the gland lumen ; it 

 is not, therefore, unreasonable to suppose that a similar action can 

 take place in the intestinal absorbing cell. 



We conclude that in certain animals, such as the dog, fats are absorbed 

 partially as dissolved fatty acids,' and partially as dissolved soaps ; while 

 in other animals, such as the white rat, fats are chiefly, if not entirely^ 

 absorbed as dissolved soaps. 



" The Gaseous Constituents of certain Mineral Substances and 

 Natural Waters." By WILLIAM RAMSAY, F.R.S., and 

 MORRIS W. TRAVERS, B.Sc. Received December 30, 1896, 

 Read February 4, 1897. 



It is still uncertain whether helium is a single elementary gas or a 

 mixture of two or more gases. If a mixture, it is probable that they 

 should occur independently, and that the proportion of the con- 

 stituent gases should vary in samples from different sources. During 

 the past year the gases obtained from a large number of minerals and 

 natural waters have been examined with a view to investigate this 

 point, and, also, to determine whether any new gaseous element could 

 be discovered. In every instance the results have been negative ; no 



reaction to litmus. Although fats are not absorbed in the form of an emulsion, it 

 is evident that the formation of an emulsion in the intestine must enormously 

 increase the surface exposed to the action of the intestinal fluids, and proportion- 

 ately increase the rate at which the fats are decomposed and dissolved. 

 * Munk, ' Virchow's Archiv,' vol. 95, 1884, p. 408. 



