$n Hepatic Air* ,143 
ib that, I prefume, metallic fubftances can never be found in 
hepatifed mineral waters. 
SECTION VI. 
Of the Properties of Alkaline Liquors impregnated with Hepatic 
Air . 
I have already mentioned the proportion of air they are able 
to take up. Colourlefs fixed alkaline liquors receive a brownifh 
tinge from this air. The refiduum they leave is of the fame 
nature as the part they abforb. 
A cauftic fixed alkaline liquor, faturated with this air, precipi- 
tates barytes from the acetous acid, of a yellowifh white colour. 
It alfo decompofes other earthy folutions, and the colour of the 
precipitates varies according to their purity, and perhaps this 
teft might be fo far improved as to fupply the place of the 
Pruffian alkali. 
It precipitates the folution of vitriol of iron , and alfo ma- 
rine fait of iron, black; but this latter generally whitens by 
agitation. That which I ufed was very faturate. 
The folutions of fiver and lead are alfo precipitated black 
with fome mixture of white ; that of gold is alfo blackened ; 
but that of platina becomes brown. 
Solutions of copper let fall a reddifh black or brown preci- 
pitate. 
Sublimate corrofve by this teft difcovers a precipitate partly 
white and black, and partly orange and greenifh. 
In the nitrous folution of arfenic it forms a yellow and 
orange ; and in that of regulus of antimony , in aqua regia, an 
orange precipitate mixed with black. 
Nitrous 
