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, b, b, is composed almost 

 wholly of pebbles of all sizes, crowded together in complete disorder. The hori- 

 zontal lines of «, 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. 



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 rorre- 



s. lied sandstone, c. Conglomerate, four hundred feet thick, rt, Red trap, two hundred feet thick, bt. ISlack, compact, and 

 amygdaloid trap. d. Drift, a, a, a. Thread of stream, — chute forty-two feet, perpendicular. 



Sec Specimen 66 of wy collection 



