of Atmospherical Air, ec. 143 
phlogiston; according to which, .a calx is reduced 
to its metallic state by acquiring phlogiston: but 
here it is said to be reduced by tie with phlo- 
giston. 
When mercury is dissolved in the nitric acid, ni- 
trous air is produced; which the phlogistians ascribe 
to the phlogiston of the metal. If therefore it were 
true, that precipitate per se retains all or nearly all 
‘the phlogiston of the metal from which it comes, it 
would likewise produce nitrous air during its solu- 
tion in the nitric acid. But this is not the case. 
As mercury in dissolving in nitric acid produces 
nitrous air, .it cannot be denied that the red oxyd, 
obtained by these means, has parted with its phlo- 
giston; and yet it is reduced to its metallic state by 
mere heat, without any addition whatever. To ob- 
viate this objection, he asserts, that it loses only part 
of its phlogiston; and that it has a deficiency of 
phlogiston when reduced by mere heat: but that, 
on the contrary, the metal obtained by reducing 
precipitate per se in inflammable air has a redun- 
dancy of phlogiston. This assertion leads him to 
another of equal probability: viz. that mercury, 
whether it have a deficiency or a redundancy of 
phlogiston, will, in all chemical processes, exhibit 
the same phenomena! 
It is surprising into what absurdities and contra- 
dictions this erroneous theory misleads its ablest 
advocates. ‘They set out by declaring, that a me- 
