

«.-3 





pan 



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/Inalyfts of the Air. 





*47 



Which Hidden and fatal effect of thcfc 

 noxious vapours, has hitherto been fuppoicd 

 to be wholly owing to the lofs and waftc of 

 the vivifying fpirit of air; but may not 

 unreafonably be alfo attributed to the lofs 

 of a confidcrablc part of the air's clafticity, 

 and the groflhefs and denfity of the vapours, 

 which the air is charged with ; for mutu- 

 ally attracting particles, when floating in To 

 thin a medium as the air, will readily coa- 

 lefce into groflfer combinations : Which 

 effect: of thcfc vapours, having not been duly 

 obferved before , it was concluded, that 

 they did not affect the air's clafticity ; and 

 that confequcntly, the lungs muft needs be 

 as much dilated in infpiration by this, as 



by a clear air. 



But that the lungs will not rife, and di- 

 late as ufual, when they draw in fuch noxi- 

 ous air, which decreafes faft in its clafticity, 

 I was allured by the Experiment I made on 

 my fclf in Expcr. 107. for when towards 

 the latter end of the minute, the fuffocating 

 quality of the air in the bladder was grea- 

 teft, it was with much difficulty that I 

 could dilate my lungs a very little. 



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