CONTENTS. Ixvii 



Se&.VIII. Experiments fhewing that plants have 

 a remarkable power to correct bad air in the 

 day, p. 219 



IX. Experiments fhewing that acrid, flinking, 

 and poifonous plants yield by day-time as good 

 dephlo^ifticated air as any others, 22a 



X. Experiments jhewing that all flowers in ge- 

 neral yield a very poifonous air, though in a 

 very fmall quantity, and are apt to fpoil a 

 great quantity of good air by day and by night , 



XI. Experiments Jhewing that roots of plant s % 

 when kept out of the ground, yield, in ge- 

 neral, bad air, and fpoil common air at all 

 times, fo?ne few excepted, 228 



XII. Experiments jhewing that all fruits in ge- 

 neral yield bad air, and infect common air at 

 all times, but principally in a dark place and 

 in the night, 230 



XIII. Experiments fhewing that no part of 

 plants improve ordinary air, or yield dephlo- 

 gifticated air, but the leaves and the green 



■ 'fialkst 238 



XIV". Experiments jhewing what kind of water 



objlr utls leaf the natural operation of leaves 



yielding dephlog'flicated air, 240 



XV. Experiments fhewing to what degree of pu- 

 rity dephlogijlicated air may be elaborated by 

 vegetables, 247 



XVI. Experiments fhewing the effecl of plants 

 tipon inflammable air, 252 



e z Se&. 



