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EVIDENCES OF GLACIATION 191
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moldings,
and the rocks they occur upon are polished and oftentimes lustrous. The
channels diminish in size to the faintest striae which, like sharp
scratches, cover the surface, running along at times in parallel
series, or diverging in different directions, as though the great
primitive plane had varied its course over them, scoring with exquisite
fineness.
In
the same region they have the same direction. They seem, as it were,
with us, to stream from the north, and wherever other scores
contravene this, these secondary markings are themselves harmonious,
indicating some subsequent action upon the rocks, in character similar
to the first, though varying in its motion and probably restricted in
its extent and importance.
Thus
the scores upon the rocks of New England point northwest and southeast,
and only local derangements disturb this prevailing direction. The
easting increases as we progress to the ocean, reaching its maximum in
Maine and the borders of Canada; while, as we retire from the margin of
the States, we observe that the scratches and grooves acquire a
north-and-south direction, becoming nearly meridional over New York,
and there slowly swing round to the west, until in Ohio, Indiana,
Illinois, Wisconsin, and the western limits of the continent they lie
pointing northeast and southwest. In the east they assume a rudely
outlined radiation from the highlands of Canada, and stretch out from
a hypothetical center like the multiplied spokes of a great wheel. In
Switzerland they sweep down and out from the central ranges of the Alps
in all directions, and, while locally uniform, they converge from the
south, and east, and north, and west, toward the lofty slopes and
pinnacles of this assemblage of mountains. Over West Russia and
Northern Europe, where the markings are discovered, they indicate the
Scandinavian mountains to have been the seat of whatever disturbance or
agency has fluted and engraved the continent. Similarly as the rocks
lie related to the Highlands of Scotland, the Lake Hills of England, or
the mountains of Wales, the striae im-
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