\ 



TIWiOUY OF RESPIUATIOT^. 7^ 



From the firft experiment we learn, that (he fuper-acefate Saper -acetate oT 

 <&f lead is more foluble in water th;in is generally imagined ; ^j^^^^^ gencrall'y 

 Dr. Thomfon obferves, that it is difToIved only fparingly *; yet fuppoled. 

 we tind that 100 parts of water retain in Tolution 27 parts of 

 the fait. 



III. 



A concife View of the Theory of Refplration, By 

 W. Biiande', Ej'q. (pTum the Author,) 



A HE term refptralion implies the reception of atmofpherle Refplratron^ 

 air into the lungsy a«d its fubfequent emiffion, after having 

 produced changes in the blood necellary to the continuaiice of 

 life f. 



No other gafeous body being capable of producing thefe ^'^^^}^ not be ex* 

 changes, it was natural to fuppofe, that until we became ac- armofphere^was 

 quainted with the component parts of the atmofphere, very analyfed. 

 little of the true nature of refpiration could be underftood. 



The fiift great ftep towards the analylis of the air was made Discoveries of 

 by Dr. Prieftiey, who in the year 1774 difcovered oxigen gas, ^"^^^^J* 

 called by him dephlogifticated air. But we are indebted to ^nd Lavoifieju. 

 LavQifier for the moft accurate inveltigation on this fubje<fl; 

 who from many experiments, which it is not neceffary here to 

 relate, concluded that atmofpheric air was compofed of oxi- 

 gen and azot, in the proportion of about 27 parts of the former 

 to 73 of the latter. The air alfo contains a fraa-ll quantity of 

 carbonic acid^ and a confiderable quantity of water (fubjedl 

 however to much variation) is always fufpended by it. 



Some of the gafes are totally unrefpirable, that is to fay. Gas which cm* 

 incapable of being taken into the lungs; for whenever this is "**^ be rcfpired, 

 r - J- T- o- r 7 • 1 • or admitted mt» 



attempted, a Ipalmodic affeciion oi the epiglottis takes place, the lungs. 



■which by clofing on the larynx, Ihuts up all communication 

 with the organs ot refpiration. To this clafe boJong all thofis 



* Thomfon's Chemiftry, HI. 53. 



t Refpiration has been divided into, 1. Infpiration, or th€ in- 

 grefs of air into the cells of the lungs, cauled by the enlargement 

 of the cavity of the cheft j 2. Into expiration, or the egrefs of air 

 tiom the lungs, caufed, by the contra'5tion of the cheft. 



gjafeous 



