DETAILED SECTIONS. 443 
a chute of twenty-eight feet in height in the trap, there is a well-defined vein of 
laumonite and calcareous spar, bearing southeast by south, very thin and branching. 
I saw no copper in it, but the explorers who located it report a few particles. There 
is at the same place a cross course, ten feet wide, with good walls, the intermediate 
space filled with a broken, heterogeneous mass. The wall-rock is a soft, red amyg- 
daloid, very loose, and jointed and bedded, without regularity; a majority of 
the joints run north 30° east and south 65° west. There are other laumonite 
veins, apparently barren and irregular, like seams; and also cross courses of 
unequal width and direction. The trap at the head of the chutes is not uniformly 
bedded, but the beds incline to the eastward more than to other directions. Pur- 
suing the channel downward, through a narrow and tortuous bed, with vertical 
walls on each side, the conglomerate is met with, and at first presents an appear- 
ance of horizontal stratification, as represented in the preceding section, No. 2, in 
which the thin-bedded horizontal portion, a, has frequent lines of stratification, 
that pass directly through the pebbles. The adjacent mass, 8, }, is composed almost 
wholly of pebbles of all sizes, crowded together in complete disorder. The hori- 
zontal lines of a, although apparently lines of lamination, are probably due to 
jointage, for in all other places the stratification is nearly at right angles to these 
lines, dipping north-northwest 85°. 
We perceive, in the hard strips of the soft bed, s, a repetition of what was 
observed in the Montreal section. There is a similar bed of conglomerate, twenty 
feet thick, detached from the main bed. The altered and slaty beds, d, e, have 
their representatives in the Montreal section. Judging by external signs, the 
prospect for mining here is far less promising than at the Montreal. 
The surface of the red clay is about two hundred and fifty feet above the Lake, 
showing a thickness here of more than one hundred feet. The sandstone is visible 
in the channel for one and a half miles below the last section, the dip remarkably 
uniform, north-northwest 82° to 87°, exhibiting some thin bands of conglomerate, 
very soft, and conformable to the general dip. 
Be ai Nise Meet .Y 
TS 
HERAT LEALT ETT 
s. Red sandstone. c. Conglomerate. four hundred feet thick. rt, Red trap, two hundred feet thick. 6¢. Black, compact, and 
amygdaloid trap. d. Drift. a, a, a. Thread of st: »—chute forty-two feet, perpendicular. 
Tf et 2s a 
* —_ ~r st 7 
ut * 
alz bc des & f 
~~ 
Little need be said of the section here given. Mr. D. Tyler, for the “Charter 
Oak Mining Company,” assisted by Mr. Erastus Heard, made a location on these 
falls. In the space of half a mile, the descent is eighty-four feet, to the foot of the 
last chute, which is perpendicular, and forty-two feet high. 
At the head of this fall, is a crevice containing green earth, with a trace of the 
green carbonate.* There are other imperfectly developed fissures or seams in the 
bed of the stream, where the trap is visible, for nearly a mile above the falls, 
on the east branch. The fork here divides at the foot of the falls shown in the 
section. On the west branch, at seventy rods from the junction, is a corre- 
See Specimen 66 of my collection. 
