imprisoned in its bosom, and these poured to the surface, as igneous, intrusive, or trap-rocks.  Where the great breaks were not deep enough to reach the central fires, they left mighty fissures in the surface, which, in the Scandinavian regions, are known as fiords, and which constitute a striking feature of the scenery of these northern lands; they are great canals—­hewn, as it were, in the rock—­with high walls penetrating from the sea far into the interior of the land.  They are found in Great Britain, Maine, Nova Scotia, Labrador, Greenland, and on the Western coast of North America.

David Dale Owen tells us that the outburst of trap-rock at the Dalles of the St. Croix came up through open fissures, breaking the continuity of strata, without tilting them into inclined planes."[1] It would appear as if the earth, in the first place, cracked into deep clefts, and the igneous matter within took advantage of these breaks to rise to the surface.  It caught masses of the sandstone in its midst and hardened around them.

These great clefts seem to be, as Owen says, “lines

[1.  “Geological Survey of Wisconsin, Iowa, and Minnesota,” p. 142.]

{p. 52}

radiating southwestwardly from Lake Superior, as if that was the seat of the disturbance which caused them."[1]

Moreover, when we come to examine the face of the rocks on which the Drift came, we do not find them merely smoothed and ground down, as we might suppose a great, heavy mass of ice moving slowly over them would leave them.  There was something more than this.  There was something, (whatever it was,) that fell upon them with awful force and literally smashed them, pounding, beating, pulverizing them, and turning one layer of mighty rock over upon another, and scattering them in the wildest confusion.  We can not conceive of anything terrestrial that, let loose upon the bare rocks to-day, would or could produce such results.

Geikie says: 

“When the ‘till’ is removed from the underlying rocks, these almost invariably show either a well-smoothed, polished, and striated surface, or else a highly confused, broken, and smashed appearance."[2]

Gratacap says: 

“‘Crushed ledges’ designate those plicated, overthrown, or curved exposures where parallel rocks, as talcose schist, usually vertical, are bent and fractured, as if by a maul like force, battering them from above.  The strata are oftentimes tumbled over upon a cliff-side like a row of books, and rest upon heaps of fragments broken away by the strain upon the bottom layers, or crushed off from their exposed layers."[3]

The Rev. O. Fisher, F. G. S., says he

“Finds the covering beds to consist of two members—­a lower one, entirely destitute of organic remains, and

[1.  “Geological Survey of Wisconsin, Iowa, and Minnesota,” p. 147.

2.  “The Great Ice Age,” p. 73.