On 'Respiration. 379 



faction tbaa if I had taken out a patent and made a fortune 

 by it. With regard to any reward for my experiments 

 and trouble I am not sanguine : if it be said of me that I 

 have been useful to my country, and have not lived m vam, 

 I shall be satisfied. 



As the idea of flax being furnished by broom is new, 1 

 have sent specimens of the flax to the Royal Society, to the 

 Board of Agriculture, to the Society of Aris, to the British 

 Museum, &c.; and I have sent you the inclosed specimens, 

 that vou may inform the public in what manner the poor, 

 in counties where broom is plentiful, if they want employ- 

 ment, may find one, easy and by no means unprofitable. 



I am, &c. 



James Hall. 



P.S. The fibres of all kinds of mallows I find are un- 

 commonly beautiful ; particularly the malva sylvcstrls. 

 They are finer and prettier than camel's hair, which they 

 somewhat resemble; and there is no difficulty in procuring 

 thcni. 



LIV. On Respiration. By William Allen, Esq., F.R.S. 

 and William Hasledine Pepys, Esq., F.R.S.* 



One of the most prominent features in our last communi- 

 cation was the evolution of a considerable quantity ot azote, 

 when oxygen gas nearly pure was respired ; and although 

 a considerable part of this azote must undoubtedly be at- 

 tributed to the residual gas in the lungs, after the most 

 forcible attempt at expiration, yet the fact seemed to de- 

 mand still turther investigation, it appearing of consequence 

 to ascertain whether the increase of azote was uniform 

 throughout the latter stages of the experiment, or soldy 

 confined to the earlier periods. 



By adverting to our former paper, it will be found, that 

 in an experiment where more than 3000 cubic inches of 

 oxygen passed through the lungs in seven nunutes and a 

 quarter, 62 cubic inches of azote were found in the first 

 250 cubic inches expired, though the gas originally con- 

 tained but 2-3 per cent., or only 6 cubic inches in this 

 quantity, in the two next portions expired, conbisting of 

 562 cubic inches, we found 56 cubic inches ot azote, 

 thou.jh this quantity of gas, before it was respired, con- 

 tained only 14; these, first portions, were given oil m about 



• From Philosophical Transactions, Part 11., for 1809. 



two 



