20 On the Serpentine Rocks of Hoboken, N. J. &c. 
ging clusters, of a pale green or gresnisli-prey colour and 
a pearly submetallic lustre, soft enough to be easily cut by 
a knife, and almost perfectly opaque, enenibies and Site, 
Its powder is unctuous and shining. By the influence of 
the weather it becomes whitish and more brittle, Its spe- 
cific gravity by Nicholson’s balance was 2,470. 
Chemical characters. Before the blowpipe it decrepitates, 
PREPS: and slightly exfoliates without showing any sign of 
10. 
100 grains after an hour’s ignition lost 15 per cent. and 
the fragments were then sufficiently hard to scratch glass. 
The remaining 85 grains were dissolved in nitric acid and 
formed a thick and partly gelatinous mass. After the so- 
lution appeared complete, there remained on filtration and 
desiccation by ignition 35 grains of silex, which with pot- 
ash readily fused with effervesence into a pellucid glass. 
The metallic. stay was then. -paceinitaiad- by penavinte 
of potash and by the grass green colour of the solu ere ap 
d mixed with a minute portion of chrome. This pre 
cipitate of a deep blue amounted when dried, after timid 
the pines reduction, to one half a grain of the protoxid 
of iro 
Lassi the sobation to dryness and lixiviating, there 
remained one grain more of silex 
The eee Drexiouely ascertained to 2s principally mag- 
nesian, was uow precipitated by caust he 
prea boiled to aeparete the alumnine, it might con- 
ain. 
The alkaline liquor was again shperenthrated with muri- 
atic acid, to which — was added, but without produ- 
ee: any precipitatio 
he precipitate by caustic e potash, after edulcoration and 
ignition, sufficient to expel the carbonic acid, weighed 46 
grains, and was mg redissolved in sulphuric acid, which 
ohet repeated digestion and solution, deposited five and a 
half eon of gypsum, equivalent to two grains of lime. 
