190 Account of the Geology, Mineralogy, Scenery, sc. 
in a northwest direction for several miles, with ponds of 
magnitude and depth. A detached mountam range of con- 
siderable elevation is situated north of the Pracknes ridge ; 
it sweeps In a semicircular course several miles, taking its 
tise and termination near the Highlands. Many of the 
summits are under cultivation and afford fine views of the 
immense secondary valley situated between the Highlands, 
the Hudson and the Pracknes ridge. Greenstone of a fine 
grain is the rock in place, in which I found prehnite and stil- 
bite imbedded. ‘Tothe East of the Pracknes ridge is sit- 
uated another section of the extensive greenstone ranges 
called the Totoway mountain—this ridge rises near the 
Pracknes mountain six miles from Patterson, and connects 
itself with the Newark chain at the great falls 3 it is im ma- 
ny places free from rocks, but on the East, precipices of 
considerable extent and height with waving or denticulated 
mural faces are sometimes observed, presenting columns ap- 
proaching to basaltic regularity. An insulated semicircu- 
lar wall of greenstone, with projecting columns occupies a 
summit of the Totoway ridge, bearmg some resemblance 
to a castle or fort inruims. Sandstone quarries are ob- 
setved in several places at the base of the greenstone ridg- 
es. A quarry situated three miles northwest of Patterson, 
at the Pracknes mountain affords the best freestone of New- 
Jersey. Fine red and gray sandstone embracing some mi- 
ca, alternates with argillaceous strata, dipping under the 
greenstone with a western inclination of about 12 degrees. 
Bituminous coal, in layers of about two inches in thickness 
has been frequently found at this and other parts of the 
Pracknes ridge, in connection with sandstone and shale. This 
neighbourhood exhibits many indications that more valua- 
ble beds of this combustible exists below. Gneiss, granite, 
pudding and sandstone, in rolled masses, appear abundant 
on the surface in many parts of this region. ‘The green- 
stone of the Pracknes range rarely presents interesting im- 
bedded minerals. I have however found, ina few places, 
prehnite, agate, chalcedony, and a mineral answering to the 
description of cacholong. At the falls of the Passaic near 
Patterson, perpendicular mural precipices of greenstone, 
with wide vertical fissures are observed, and amorphous 
masses at the base. ‘The lower strata of this rock contain 
much argillaceous matter, which partially takes the place of 
