98 Geological Notes. 
perhaps a majority of them intersect the strata, nearly at right angles. 
The dip of the strata is very variable. In many places the strata are 
nearly, or quite vertical, and in some others they approach the hori- 
zontal, and vary indefinitely between these limits, and in some local- 
ities they are bent or contorted so as in a short distance to assume ey- 
ery possible variety of dip. ‘The general line of bearing of the strata, 
corresponds with the direction of the chain of mountains, which is 
about N. N. E. and sss. w. Augite, serpentine, the primitive lime- 
stones, magnetic oxide of iron, and various mixtures of these with 
each other, and with other minerals, constitute almost innumerable 
beds, of small extent, scattered through the Highlands, in every di- 
rection, without any regularity in their disposition. Nearly all the 
varieties of pyroxene are found in our augite rocks.  Silicious lime- 
stone occurs in but one locality, in place, in the Highlands, buts 
scattered in bowlders and gravel in every direction through them. 
_ Pyrophyllite, (as it has been recently called in the scientific jour- 
nals) occurs near West Point in a vein, a foot in width, traversing 
y augite. A fragment of it, one eighth of an inch in _ thickness, 
exfoliates by heat to such a degree as to become an inch thick. 
A conglomerate rock is now in process of formation, about one 
mile n. N. w. of West Point, and on the shore of the Hudson, a fine 
section of it is visible. The cliff rises nearly vertically from the 
shore from twenty to forty feet, and is composed of fragmentary 
matter, varying in size, from fine gravel, to bowlders weighing se 
eral hundred pounds. ‘These materials are passing into the state of 
a solid aggregate, by the continual deposition of calcareous matte! 
between the fragments. The gravel above, as well as the aggregal 
itself, is composed mostly of pebbles and pieces of various sizes; of 
slate, lime-stone, hornstone, granite, sienite, &c. The lime-stone is 
continually undergoing solution by the infiltration of water, an¢ ® 
skeleton of hornstone, or of loose silicious matter, frequently contail- 
ing the impressions of terebratule, and some other species of shells 
remain. ‘The calcareous matter dissolved in the upper part of the 
bed, is mostly deposited, as is evident on inspection, in the lower 
portion of it, and in some places, ordinary specimens of dog-tooth 
spar, (chaux carbonatée Métastatique of Haiiy) may be obtained, it 
vesting the pebbles. 
Scapolite and sphene are uniformly associated with the augit? 
rocks in this vicinity. Hornblende exists as a constituent pat? 
the sienitic rocks, but it not unfrequently occurs forming distinct 
eds. The summits of several of the hills in this vicinity, are ¢P” 
