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The Catskill Mountains.—On the west side of the Hudson, the Catskill Mountains rise, in their highest peaks, about 3600 feet above the sea, and nearly that height above the river, which is tidal far above Albany. The strike, both of the Silurian and Devonian rocks of the lower bills, is nearly north and south; and after traversing a broken country for ten or twelve miles, the Catskill Range itself rises in a long north and south escarpment, nearly 3000 feet above the hilly ground that lies between it and the river. At the town of Catskill, striations on the smoothed surfaces run nearly north and south, following the trend of the Hudson Valley between the Catskill and Green Mountains; and at other points ,between the river and the mountains they run about N.N.E. I was anxious to discover if on the Catskill Mountains themselves there were any signs of true glacier-action, this range being much higher than any other elevations which I had an opportunity of ascending. The low country is as much or even more glaciated than Anglesea ; and the mountains are as high as Snowdon ; and—though in latitude 42° N., whereas North Wales is in latitude 52° to 53°-other conditions seemed very much the same. Observations also in this region were of more importance, since I am not aware that evidences of any kind of glaciation on these heights had previously been definitely recorded. The accompanying sketch-map (fig. 3), constructed on the spot, will give an idea of the topography of that part of the range which I examined.
I ascended from the mouth of the valley misdamed “Sleepy Hollow," up the steep and winding road to Mountain House. The mountain is almost everywhere covered by dense wood, so that, except on the roadside, it is comparatively rare to find the
may have been so completely covered with thick snow and ice, that, always pressing downwards from the snow shed, the striations were formed E. and W., or transverse to the trend of the ranges; but in that case both in the valleys and on the sides and summits of the hills, when fairly submerged, we might expect north and south striations formed by the grating of bergs during the deposition of the northern drift. In the case of isolated bills the striæ ought also to radiate from their summits. I observed none of these appearances, but had not sufficient time to search for them in detail. It is clear that the E. and W. striations across the range were not made by a general terrestrial glaciation during, or after, the re-elevation of the country, for then the boulders, &c. transported from low to high levels would all have been swept down again into the hollows.
rocks uncovered. In “Sleepy Hollow" the road runs nearly east and west. Occasionally local drift lies on its steep northern side; and on the smoothed surfaces of rock I observed a few striations from N. to S., and others from E. to W. The former ran up and down the hill towards the brook ; and the latter were on the vertical faces of the little cliffs, up and down the valley.
Passing the bend where the road crosses the brook, striations became frequent; and I was surprised to find that all of them ran nearly N. and S. along the flanks of the escarpment, and not from W. to E. down the slope of the hill. For a time I thought that as I ascended higher they would cease altogether ; but, so far from this being the case, I was alike pleased and astonished Fig. 3.–Sketch-map of a portion of the Catskill Mountains, shoro
ing the Directions of the strice near Mountain House.
to find that they continued equally strong and frequent up to the plateau on which the Hotel stands, 2850 feet above the sea ; and all, but a few of the last, ran not across, but along the face of the escarpment.
By twenty compass-observations made on clearly defined stríations the chief grooves run between S. 22° E. and 8. 56° W. Among these, one runs S. 22° E., two S. 10° E., two N. and S., one S. 10° W., six S. 22° W., one S. 30° W., two S. 55o W., and one W. 10° N. The variations seem somewhat connected with bends and other irregularities in the face of the great escarpment, One of the observations (8. 55o W.) was made on the well-scratched plateau on which the Hotel stands, about 120 feet above the lower part of a gorge which here crosses the watershed towards the lakes. in which the stream rises that, further down, forms the Falls of Catskill. The other is at the bend of the road N. E. of the hotel, near the head of the stream. In the lowest part of the gorge, on the summit of the watershed, many square yards of smoothed rock are exposed a little off the road ; and in this plateau numerous main grooves are seen, passing across the hill, and nearly at right angles to most of those observed during the ascent, seemingly pointing to the fact that the icebergs, which striated the eastern flanks of the mountains in a N. and S. direction, when the whole was nearly submerged, here found a passage or strait, through which they sometimes floated and grated the bottom in a direction quite across that which they were forced to follow when passing along the great escarpment that now faces the Hudson.
Though the principal grooves run in the directions stated, many minor striations, such as might be expected from floating ice, cross them at various angles.
From this point I made two excursions into the higher parts of the range, in the hope of finding similar markings: but so dense is the forest, that it took two hours to walk a milo: and though in several places the rocks were exposed, they were too much weather-worn to afford all the usual indications. Nevertheless the rounded contours of all mountain-tops always impressed me with the idea of glacial abrasion; and if, as I believe, they were contoured and striated by floating ice, then the drift-sea of the Hudson Valley was at least 3000 feet deep,--and probably more, if, as is likely, the higher peaks were also submerged. Judging by the general uniformity that seems to have prevailed over North America in changes of level, it would probably be safe to infer that this
submergence also extended to the Laurentine and other mountainchains in the eastern part of North America
Allowing that the striations on the eastern flank of the great range were made by floating ice, it still does not follow that in the interior there should be no traces of glaciers in the narrow valleys on the opposite watershed, -such glaciers, if they ever existed, being like some of those in North Wales, of later date than the emergence of the country from the drift sea. I had an opportunity of testing this. In the gorge close to the south shore of the little lakes, the striations still run W. 10° N.; and below that point the valley, descending westward from 5° to 10°, is covered with boulders of Catskill sandstone (see fig. 3). About a mile and a half down, at the Falls of Catskill, the valley suddenly deepens; and about two miles further it curves round to the S. E. and finally the stream escapes from the Catskill Range, and flows towards the Hudson. On either side the valley is bounded by high steep slopes and abrupt cliffs; and the height and form of the ground is such that, under · Fig. 4.-Section of the Valley below the Falls of Catskill,
showing boulder-drift covering its sides.
2. Red Sandstone and Conglomerate.
favourable circumstances, it seemed as well adapted for the forma tion of a glacier as many of the valleys of North Wales, had the conditions for such a result been alike propitious. But the evidence is opposed to any such conclusions. I saw no well-marked roches moutonnées, no traces of moraines; and the forest-clad slopes are mostly covered with deep local gravel and boulder-drift, many of the stones in which are scratched. Had a glacier existed there since the drift-period, the drift would have been ploughed out of the valley by the glacier, in the manner that it was removed by the glaciers of the Passes of Lanberis and Nant Francon in North CANADIAN Nat.
VOL. IV. No. 5. Wales ; whereas nothing has been removed, except a portion of the drift by the torrent that now flows in the bottom* (see fig. 4).
Probable equivalency of the Drift of the Hudson Valley with that of Lake Champlain and of Montreal.-I have now a few remarks to offer on a part of the drift itself. South of Albacy the Hudson flows through a broad valley full of minor undulations, between the Catskill and the Green Mountains. On the banks of the river are extensive beds of sandy clay, from which the bricks are made of which Albany is built. The city stands on this claywhich extends far down the river towards New York, and northward into the Valley of the Mohawk, and as I shall show, probably also into the valley of Lake Champlain. Beyond the river-bank it stretches E. and W. on the undulating ground towards the mountains, rising, six miles in the direction of the Helderberg, far above the level of the river. At its edge, Mr. Hall pointed out to me that the sands, gravels, and boulder-clay of the ordinary drift pass under it. The superficial deposits of the valley of the Hudson therefore, consists of two subdivisions: first, the older boulderbeds; and, second, the laminated clay, which at Albany is a thick formation, finely and evenly bedded in layers of 1 or 2 inches thick, the argillo-arenaceous laminæ of which graduate into each other in shades of bluish-grey, brown, and brownish-yellow, producing a beautifully ribanded aspect, and giving the impression of a succession of repeated alternations of tranquil depositions in still water. Boulders occur in it rarely; and the top is covered with sand, which may possibly represent the uppermost sandy beds of the St. Lawrence and Ottawa districts. I searched in vain for fossils, both in the paper-like laminæ of clay, and in the abundant concretions, resembling those of the valley of the Ottawa which contain the fossil fish Mallotus villosus.
The Hudson runs nearly straight north and south ; and forty miles above Albany, at Sandy Hill, the Champlain Canal joins the river to Lake Champlain, which also trends north and south, and, separated by a low watershed, lies in what must be considered a continuation of the valley of the Hudson. The lake is 90 feet above the level of the sea; and on the Vermont shore, 150 feet above the sea, there is a section of six feet and a half of regularly
• I was informed by Professor Agassiz, that in the White Mountains, which rise more than 6000 feet above the sea, there are in the higher regions distinct indications of ancient glaciers; and if this be the case: the same phenomena may be looked for in the mountains of Gaspé.