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SECTION XL 



Experiments Jhewing that roots of 

 plants when kept out of the ground 

 yield, in general^ bad air^ andfpoil 

 common air at all times ^ fomefezv 

 excepted. 



^% 71. THREE handfuls of roots 

 Iksd™ ^ muftard plants, warned clean, 

 troycd * were put in a jar full of water in 

 the ordinary way, and expofed to 

 the fun during fix hours ; when 

 fome air was obtained, which ex- 

 tinguifhed a candle directly. 



72. Two handfuls of roots of 

 common rufhes^ well cleaned from 

 dirt, were in the fame manner ex- 

 pofed to the fun during feven hours ; 

 when a fmall quantity of air was 

 6 obtained^ 



