Parts of Water and of Dephlogifiicated Air, 345 
* the atmofphere, or from dephlogifticating the fixed air which 
** they are known to contain,” 
It is very probable, that the dephlogifticated air extruded from 
- growing vegetables may be owing to their dephlogifticating the 
water they grow in; but it appears more probable, that the 
plants have a power of dephlogifticating the fixed, or phio- 
gifticated, air of the atmofphere. 
«¢ When dephlogifticated and nitrous air are mixed, the de- 
¢ phlogifticated air feizes part of the phlogifton of the nitrous 
‘¢ air.” The water contained in the nitrous air, and the other 
part of the phlogifton, unite with the nitrous acid, which ther 
afflumes a liquid form, or at leaft that of a denfe vapour; “ and 
<< that part of the latent heat of the two airs not effential to the 
<¢ new combination is fet at liberty *.” 
In the combuftion of fulphur the fame thing happens, but 
in a greater degree ; for the vitriolic acid, having a much weaker 
attraction for phlogifton than air has, abandons it almoft en- 
tirely to the latter, which is thereby converted into water, and 
in that form attracts the vitriolic acid, and reduces it to a liquid 
ftate. ‘The fame reafoning may be applied to the combutftion 
~of phofphorus, which is attended with fimilar effects. 
* J cannot take upon me todetermine, from any facts which have come to my 
knowledge, whether any part of the dephlogifticated air employed in this experi- 
ment is turned into fixed air; but I am rather inclined to think that fome part is, 
becaufe the quantity of heat, which is feparated by the union of the two airs, 
does not feem to be fo great as that which is feparated when the dephlogifticated 
air is wholly changed into water: yet fome water appears to be formed, becaufe 
when the mixture is made over mercury, the folution of the mercury in the ni- 
trous acid affumes a cryftallized form, which, however, may be due to the watery 
part of the nitrous air. 
Vot. LXXIV. LZ 15.1 
