C *89 ) 
He fhews the Miftake of thofc that (uppos’d 
the Air did not lofe _ its Elafticity, but its Vivifying^ 
Spirit by Vapours, by an Experiment made upon a 
Dog, into whofe Lungs he drove by Force that 
effete Air which the Dog by his own Adfion cou'd 
not draw into his Lungs j and whereas the Dog, 
then, was juft expiring by the fubfjding of his Lungs, 
he kept him alive by the forcible Impulfion ol that 
very Air, as long as he cou’d blow up the Dog’s Lungs 
with it. 
He makes it appear, that a clofe warm Air with- 
out a Communication with the outward Air, to carry 
oft' the Vapours, muft be unfit for breathing long; 
and therefore condemns the ufe of German Stoves. 
That when Animals are kill’d by Lightning with- 
out any vifible Wound, it is becaufe the Sulphure- 
ous, Steams have deftroy’d the Elafticity of the Air 
about them ; as appears by diftecfting fuch Animals, 
whofe Lungs are always found comprefs’d together 
without any Air in them. The fame alfo appears 
in Men that have been kill’d by Damps in Mines. 
Then he gives the Defcription of an Inftrument 
whereby 4 or 5: Quarts of the fame Air, fwhich in 
the common way can ferve one Man to breathe 
very little above a Minute^ may ferve 8 f Minutes 
'to breathe, by drawing in the Air which has been 
in the Lungs thro’ 4 Diaphragms of Flannel dipp’d 
in a Lixivium highly calcin’d Salt of Tartar,, and* 
afterwards dried , and blowing back the feme Air 
in fuch manner that it may at every InfpiratioH' 
return thro’ the faid Diaphragms ; which is done 
by means of two Valves. The Moifture and Sul- 
phureous Vapours of the Air are by this Contri- 
vance ftopp'd in pafling thro’ the Flanneli and there- 
by the Air continues wholefome much longer than it 
wou’d 
