1814.] Elements of Organic Nature are combined. 331 



binary oxides, the composition of which was known, and to perform 

 the experiment it) such a manner that the quantity of these binary 

 oxides p.* ' :a could be determined correctly. He burnt organic 

 subst.i 5 in oxvgen gas ; but this method, though just in principle, 

 did not enable him to determine by tbe balance either the quantity 

 of water or of carbonic acid gas formed by tbe combustion ; so that 

 his experiments could only give approximations. 



Some chemists, after Lavoisier, endeavoured to determine the 

 exact quantity of the products of dry distillation, and to calculate 

 from them the composition of the body. Such was the attempt of 

 Fourcrov and Vaeqctlin on the composition of urea, and of Dr. 

 Higgins on that of acetic acid. But the composition, and probably 

 also the quantity, of the products of distillation being only imper- 

 fectly known, it is obvious that such experiments, however exact, 

 can only afford data for calculation hereafter, when the products of 

 the distillation come to be examined and accurately known. 



Theodore do Saussure has analysed alcohol and ether in Lavoi- 

 sier's manner. Probably the results which he obtained approach 

 nearer the truth than any preceding analysis of a ternary oxide. 

 Thenard has in the same way analysed different species of ether. I 

 cannot at present do justice to the labours of these distinguished 

 chemists, as 1 have not yet employed myself in the analysis of these 

 substances. 



(To be continued.) 



Article III. 



Some further Observations on the Quantity of Carbonic Acid Gas 

 emitted from the Lungs in Respiration, at different limes, and 

 under different liratmstances.* By YVm. Prout, M.D. of the 

 Coll. of Physicians, &c. 



Various circumstances have prevented me from pursuing this 

 interesting subject in the maimer I had intended. 1 have, however, 

 occasionally tinned my attention to it, more especially with the 

 view of ascertaining whether the quantity of carbonic acid gas 

 emitted from the lungs began to increase uniformly at the same 

 hour in the morning at all periods of the year. The experiments, 

 therefore, which have been made OQ this part of the subject, 

 together with a few otheis, will constitute the chief object of' this 

 communication j which 1 wish to be considered merely as an 

 appendage to my former one. 



Sect. I. — "Experiments made to ascertain the period in the morning 



u Inn the ijiuiidttij if i tubulin at id emitted from the lungs ligun 

 to tncrean , <*." 



I im-ntioiic (1 in a note in my former paper on this subject that I 

 was paiiiculurly btruek with the sudden increase in the quantity of 



t **»• AunuU of 1'tJlatophii, vol. ii. p. 32U. 



