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^ an ; f two hours the air was fo much cor- 

 ^Jf.rec'ted, that it was found to be nearly 

 ^royed. as g 00( j as common air. 



58. A fprig of Perjicaria urens 

 was put in a phial full of air fouled 

 by breathing, fo as not to allow a 

 candle to burn in it ; it was expofed 

 to the fun during an hour and an 

 half, in which time the air was fo 

 much corrected that a candle could 

 burn in it. The fame effect was 

 obtained from a fprig of a vine, and 

 that of a camomile plant, and from 

 fome rufhes. 



59. A mujlard plant was put in 

 a jar; the ftem was cut off on a level 

 with the orifice of the jar ; the jar 

 was then inverted in an earthen pan 

 containing fome water to keep the 

 plant alive, and placed over-night 

 in a room ; next morning the air 

 of the jar was found much fouled, 



fo 



