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fpheric air, become exhaufted. This 

 ait, gathered in this manner, is 

 really dephlogiiticated air, of a more 

 or lefs good quality, according to 

 the nature of the plant from which 

 the leaves are taken, and the clear- 

 nefs of the day-light to which they 

 were expofed. 



It is not very rare to fee thefe 

 bubbles fo quickly fucceeding one 

 another, that they rife from the fame 

 fpot almoft in a continual ftream: 

 I faw this more than once, princi- 

 pally in the nytnph&a alba. 



SEC 



