In the Arctic Seas Part 34

V.--_The Superficial Deposits._

The surface of the ground, where exposed, throughout the Arctic Archipelago, does not appear to be covered with thick deposits of clay or gravel, such as are found generally in the north of Europe, and referred by geologists to what they call "the Glacial Epoch." There are not, however, wanting abundant evidences of the transport of drift materials, and there is some good evidence, collected by Captain M'Clintock, of the direction in which the drift was moved.

Specimens of granite, which I have no hesitation in referring to the characteristic granite of the west side of North Somerset, were found at Leopold Harbor (North Somerset) and at Graham Moore Bay (Bathurst Island); one of these localities is N.E. and the other N.W. of the granite of North Somerset, from which I infer that there was no constant prevailing direction for the drift ice that carried these boulders, but that they were transported to the northward in various directions, according to the varying motion of the currents that moved the ice. The boulder of granite at Port Leopold is 100 miles N.E. of the granite which gave origin to it; and the specimens from Graham Moore Bay are 190 miles to the N.W. of their source.

At Cape Rennell (North Somerset), in a direction intermediate between the two former directions, a remarkable boulder of the same granite was found, confirming the general direction of the transporting force from south to north. Its position and size are thus recorded by Captain M'Clintock:--"Near Cape Rennell we pa.s.sed a very remarkable rounded boulder of gneiss or granite; it was 6 yards in circ.u.mference, and stood near the beach, and some 15 or 20 yards above it; one or two ma.s.ses of rounded gneiss, although very much smaller, had arrested our attention at Port Leopold."

It is well known that Captain Sir Robert M'Clure brought home specimens of pine-trees found in the greatest abundance in the ravines on the west coast of Baring Island; one of his specimens preserved in the museum of the Royal Dublin Society measures 15 inches by 12 inches, and contains three knots that prove it formed a portion of the stem high above its root. The bark is not found on this specimen, which does not represent the full thickness of the tree; I have estimated that this fragment contains 70 rings of annual growth.

Similar remains were found by Captain M'Clintock and Lieutenant Mecham in Prince Patrick's Island, and in Wellington Channel by Sir Edward Belcher. On the coast of New Siberia, Lieutenant Anjou found a clay cliff containing stems of trees still capable of being used as fuel. The original observers all agree in thinking that these trees grew where they are now found; and Captain Osborne, in mentioning Sir Roderick I.

Murchison's opinion that they are drift timber, justly adds the remark, that a sea sufficiently free from ice to allow of their being drifted from the south would indicate also a climate sufficiently mild to allow of their having grown upon the land where they now occur. Mr. Hopkins, in his anniversary address as President of the Geological Society of London, has published a remarkable geological speculation, which would account for the facts above mentioned.[36] So far as the evidence of drift boulders is concerned, I have shown that the direction of the currents was from the south; a fact which falls in with the drift theory, so far as it goes.

We cannot, however, dissociate these trees from the facts connected with the distribution of the remains of the Siberian Mammoth in Asia and America. It is now known that this elephant was provided with a warm fur, and that his food was of a kind which grows even now in Northern Siberia; so that the drift theory, which was formerly supposed necessary to account for the occurrence of these remains, has now been quietly dropped, _sub silentio_, by the geologists. Many other drift theories have, in like manner, lived their short day, and gone the way of all false hypotheses; among others, the drift theory of the origin of coal.

Further investigation may show that the glacial epoch of Europe was one of a very different character in Asia and America, and that, while glaciers clothed the sides of Snowdon and Lugnaquillia, pine forests flourished in the Parry Islands, and the Siberian elephants wandered on the sh.o.r.es of a sea washed by the waves of an ocean that carried no drifting ice.

There is abundant evidence, however, that the Arctic Archipelago was submerged in very recent geological periods; for we know that subfossil sh.e.l.ls, of species that now inhabit the waters of the neighboring seas, are found at considerable heights throughout the whole group of islands.

M'Clure found sh.e.l.ls of the _Cyprina Islandica_, at the summit of the c.o.xcomb range, in Baring Island, at an elevation of 500 feet above the sea-level; Captain Parry, also, has recorded the occurrence of _Venus_ (probably _Cyprina Islandica_) on Byam Martin's Island; and in the recent voyage of the 'Fox,' Dr. Walker, the Surgeon of the expedition, found the following subfossil sh.e.l.ls at Port Kennedy, at elevations of from 100 to 500 feet:--

1. _Saxicava rugosa._ 2. _Tellina proxima._ 3. _Astarte Arctica_ (Borealis.) 4. _Mya Uddevallensis._ 5. _Mya truncata._ 6. _Cardium_ sp.

7. _Buccinum undatum._ 8. _Acmea testudinalis._ 9. _Bala.n.u.s Uddevallensis._

At the same place a portion of the palate-bone of a whale (Right Whale) was found at an elevation of 150 feet.

All these facts indicate the former submergence of the Arctic Archipelago, but this submergence must have been anterior to the period when pine forests clothed the low sandy sh.o.r.es of the slowly emerging islands, the remains of which forests now occupy a position at least 100 feet above high-water mark.

The geological map which I am enabled to publish from the data collected by Captains M'Clintock, M'Clure, Osborn, &c., is an enlargement of that which was published in 1857 by the Royal Society of Dublin, to ill.u.s.trate the fine collection of Arctic fossils and minerals deposited in the museum of that body by Captains M'Clintock and M'Clure. In perfecting it for its present purpose I have availed myself of all the other sources of information within my reach, among which I am bound to mention in particular the excellent Appendix to Dr. Sutherland's 'Voyage of the Lady Franklin and Sophia,' written by Mr. Salter, Palaeontologist of the Geological Survey of Great Britain.

Many of the mineral specimens from Greenland, and the fossils from Cape Riley, Cape Farrand, Point Fury and Brentford Bay, were collected by Dr.

David Walker, surgeon and naturalist to the 'Fox' Expedition.

FOOTNOTES:

[30] Journal of the Royal Dublin Society, 1857.

[31] Collected by Dr. Walker, surgeon to the 'Fox' Expedition.

[32] Collected by Dr. Walker, surgeon to the 'Fox' Expedition.

[33] Collected by Captain Allen Young.

[34] These specimens are "_Drift_" but are mentioned here as they were found on the carboniferous sandstone area.

[35] _Vide_ Arctic Expeditions, 1854-55, p. 254.

[36] Journ. Geol. Soc. Lond., vol. VIII. p. lxiv.