: 63 7] 
SECTION XVI: 
The power of plants in correcting bad 
air is greater than their faculty 
of tmproving good air. 
_ THE experiments already known 
of Dr. Prichiéy, by which it appears - 
that plants thrive wonderfully well 
in air fouled by breathing and burn= 
ing of candles, gave me a great 
fufpicion, that the power of plants 
in correcting bad air might furpafs 
their faculty of improving good 
common air. In order to put my 
conjecture to the trial, I placed at 
eleven o’clock, in'a warm fun-fhine, 
two jars of an equal fize, each con- 
taining an equal quantity of {prigs of 
pepper-mint,in pump water.Inone of — 
_ thefe jars was let up a certain quan- 
= tity 
val 
