142 Mr, CavVennisi's 's Experiments on AUK. 
From what has been faid, it follows, that inftead of fade 
air is phlogifticated or dephlogifticated by any means, it would 
be more ftriGly juft tocfay, iteis deprived of, on:receives, an 
addition of dephlogifticated air; but as the other expreffion is 
convenient, atid can fcarcely be confidered as improper, I thalf 
full frequently make ufe of it in the remainder of this papers 
There feemed great reafon to think, from Dr. PriesrhEy’s 
experiments, that both the nitrous aid vitriolic acids were con= 
vettible into dephlogifticated air, as that air is procured in the 
greatelt quantity from fubftances containing thofe acids, efpe- 
cially the forrier. .The foregoing experiments, however, feem 
to fhew that no part of the acid is converted into dephlogitti- 
cated ait, and that their ufe in prepdring it is owing only: fo 
the great power which they poflefs of depriving bodies of 
their phlogifton. A ftrong cotifirmation of this is, that red pres 
cipitate, which is one of the fubftances yielding dephlogifti- 
cated air in the greateft quantity; and which is prepared by 
means of the nitrous acid, contains in reality noaeid, “Vhis)] 
found by grinding 400 grains of it with fpirits of fal ammo- 
niac, and keeping thern together for fome days in a bottles 
taking eare to fhake them frequently. The red colour of the 
precipitate was rendered pale, but not entirely deftroyed; being 
then wafhed with water and filtered, the clear, liquor asked 
On evaporation not the leaft ammoniacal falt. |; : . 
It is natutal to think, that if any nitrous acid had been con= 
tained in the red precipitate, it would have united to the volas 
tile alkali arid have formed ammoniacal nitre, and would, have 
been perceived on evaporation ; but in order to, determine more 
eertainly whether this would be the cafe, I dried; fome of the 
fame folution of quickfilvet from which the red precipitate was 
prepared with a lefs heat, fo that it acquired only an orange 
colour, 
