2^4 Analyjis of the Air. 



pendicular tube, by which means the tube 

 and vial could eafily yield to the motion of 

 the Dog's body, without danger of breaking 

 the tube, which was 36 inches long. The 

 event was, that in ordinary infpirations, the 

 fpirit rofe about fix inches in the tube ; but 

 in great and laborious infpirations, it would 

 rife 24 and 30 inches, viz. when I flopped 

 the Dog's noftrils and mouth, fo that he 

 could not breathe : This Experiment fhews 

 the force with which the lungs are raifed 

 by the dilatation of the Thorax, either in 

 ordinary or extraordinary and laborious in- 

 fpirations. When I blew air with fome force 

 into the Thorax, the Dog was juft ready to 

 expire. 



By means of another (hort tube, which 

 had a communication with that which was 

 fixed to the Thorax, near its infertion into 

 the Tldorax y I could draw the air out of the 

 Thorax, the height of the Mercury, inftead 

 of fpirit in the tube, (hewing to what degree 

 the Thorax was exhaufted of air : The Mer- 

 cury was hereby raifed nine inches, which 

 would gradually fubfide as the air got into 

 the Thorax thro* the lungs. 



I then laid bare the wind-pipe, and having 

 cut it off a little below the Larynx, I affixed 



to 



