350 ESSAYS ann OBSERVATIONS 
of fatcharum Saturni, it exhibites the like pha- 
nomena. : 
From the preceeding Experiments we may ob- 
ar 
Ze Tuar this Spaw contains a principle 
of iron, which is volatile; for its chalybeate 
quality is much weakened by boiling (13), 
or even by being expofed for fome time to 
the air (12). 
2. Ir contains an iron principle, which 
is fixed; for its chalybeate, quality is not in- 
tirely deftroyed, by being expofed to the air 
(12), nor by boiling (13), nor by evapora- — 
tion to a drynefs (14, 15), nor by burning 
the refiduum (17); and, when its falt is cal- 
cined a fufficient time, it.is attracted by the 
magnet (18). 
3. Ir feems, by turning green with fyrup 
of violets, to contain an alcaline principle, 
which is likewife fixed; for neither by be- 
ing expofed to the air, nor by evaporation 
to a drynefs, nor by burning the refiduum, 
does it lofe this quality. 
As neither the water nor its falt or earth, 
make the leaft vifible effervefcence with /p7- 
ritus, or ol. vitricli, either by themfelves, or 
when 
