Mineralogy and Gieology. 269 
bluish varieties also occur, the latter highly pyritiferous and approach- 
ing argillite. The Hematite region includes within its limits the ore 
beds of Salisbury, Sharon and Dover; and traces may be observed 
more or less frequently throughout the formation from Patterson to 
Massachusetts. Mr. Percival goes on to observe :—From the obser- 
vations I haye made, I have been led to believe, that the Hematite, like 
bog ore, is of secondary formation, and is derived from the decompo- 
sition of the pyrites, contained in the mica slate.of the formation, par- 
ticularly in the black. sub-argillitic variety, and in a less degree, in the 
dark blue variety with transverse mica. Seams of Hematite may not 
unfrequently be observed in these varieties of the mica slate, which 
are besides characterized by their dark red brown rusted surface. 
The ore beds themselves present usually a distinctly stratified arrange- 
ment, in parallel beds interposed between the strata of the undecom- 
posed mica slate adjoining, and quartz veins are also found in the’ ore 
_ beds, arranged: precisely as they occur in the unaltered rock of this 
format The ore is accompanied with alternate layers of a yellow 
or reddish ochry earth, called fuller’s earth by the miners, derived ap- 
parently from the decomposition of the light grey mica slate of the 
formation, which corresponds, in this respect, with the light grey mica 
_ Slate of the preceding formation, as already obseryed. The different 
Tesults, from the decomposition of the different varieties of mica slate, 
_ May perhaps depend on the peculiar composition of each, or on the 
‘act, that magnetic pyrites abounds more particularly in the darker va- 
‘Reties; and common pyrites in the latter. The most important ore beds 
mm Salisbury, namely, the Ore Hill, and Chatfield’s, are situated on the. 
_ Cast side of the depression south of Taconic Mountain ; the others, in 
that town, along the east base of that mountain, farther north. Indian 
Pond'ore bed, (Sharon,) is at the western base of the ridge next south 
# Taconic Mountain, towards its southern termination, and the Dover 
bed; on the eastern declivity of the present formation, west. of Dover. 
. “This formation extends only a short distance along the west line of 
the state, namely, from west of Sharon village, to its northwest corner, 
te “i op included within the limits of New York and - simu 
rr 
Teed. 
es fig 
ee 
5 
FS 
S 
on 
Ls 
me 
eA 
ae 
Ff 
pe: et 
Kale 
a 
va 
a 
i 
. 
6 Subsidence of the Land at Puzzuoli, (Jameson’s Edinb. Jour., 
#1846, 385.)—-Mr. J. Smith stated to the British Association, that 
ot. en he Visited the temple of Jupiter Serapis at Puzzuoli, in March, 
i Asi, its floor was elevated about 6 inches above the level of the sea ; 
| » dat on the 11th of May, in the year 1845, it was covered to the depth 
; Of 18 inches at low water, and 284 at high tide,—the sea being calm 
tthe time. "Phe custode*of the building told Mr. Smith that this 
a Change ‘was progressive, amounting to 1} English inches per annum. 
_ SB0onp Sznizs, Vol. II, No. 5.—Sept., 1846. 35 
