C 4* ] 



ticular circumftances, to which it is 

 not eafy to be fufficiently attentive. 

 It feems, however, to be a general 

 rule, that the leaves of all plants, 

 growing in a place where they are 

 not much fhaded by other plants, 

 buildings, &x. yield, in a clear day, 

 dephlogiflicatecl air; and that this. 

 air is yielded in greater abundance, 

 and of a greater purity, when they 

 grow in open places unincumbered 

 by other plants higher than they are 

 themfelves. 



I got in general a large quantity 

 of air of a very good quality from 

 fame water plants, as from the perji~ 

 carta urens and willow. The fir 

 trees yielded alfo very fine air, and 

 in abundance. 



The nafturthim Tndicum furpaffed 

 them all in general, in regard as 

 well to the quantity as to the qua- 

 lity. 



