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bear may be seen all the year round. The Danes, at their first visit, found a human population there of 30,000; and within their own possessions there is at present a healthy, intelligent, civilised race of hunters of not less than 10,000 souls. Exclusive of home consumption, the annual exports of the settlements amounted in 1835 to 9,569 barrels of sealoil, 47,809 seal skins, 1,714 fox skins, 34 bear skins, 194 dog skins, 3,437 lbs. of eider down, 5,206 lbs. of feathers, 439 lbs. of narwhal ivory, 51 lbs. of walrus ivory, and 3,596 lbs. of whalebone.

Geologists have long taught that, at least, the west coast of Greenland is slowly sinking below the sea. This doctrine is confirmed by Dr. Brown, who recapitulates the principal points of the evidence on which it rests. The following are amongst the facts he enumerates :-Near the end of the last century a small rocky island was observed to be entirely submerged at springtide high-water, yet on it were the remains of a house, rising six feet above the ground; fifty years later the submergence had so far increased that the ruins alone were ever left above water. The foundations of an old storehouse, built on an island in 1776, are now dry only at low water. The remains of native houses are in one locality seen beneath the sea. In 1758 the Moravian Mission establishment was founded about two miles from Fiskernæsset, but in thirty years they were obliged to move, at least once, the posts on which they rested their large omiaks, or seal-skin boats. Some of the posts may yet be seen under water. The dwellings of several Greenland families, who lived on Savage Point from 1721 to 1736, are now overflowed by every tide. In one locality, the ruins of old Greenland houses are only to be seen at low water. A blubber house, originally built on a rocky islet about a furlong from the shore in Disco Bay, had to be removed in 1867, as the floor was flooded at every tide, in consequence of the gradual sinking of the islet-a fact which had long been recognised. An adjacent island, on which the natives formerly encamped in considerable numbers during summer, has become so diminished in size through slow subsidence that there is at present room for no more than three or four skin tents. Dr. Brown estimates the rate of submergence at not more than five feet in a century.

Proofs of an upward movement appear to be equally well established on the north coast, where Dr. Kane, in 1855, observed and described a series of old sea-beaches rising one over another to considerable heights above the sea-level. “I have studies," he says, “ of these terraced beaches at various points on the northern coast of Greenland. . . . As these strange structures wound in long spirals around the headlands of the fjords, they reminded me of the parallel roads of Glen Roy—a comparison which I make rather from general resemblance than ascertained analogies of causes." *

There seems a tendency to regard this upward movement in the north, as well as the downward movement in the west, as still in progress; in fact, to consider Greenland as a sort of lever, having its fulcrum somewhere between the two regions in which the opposite changes of relative level have been observed. There is nothing inconsistent in the hypothesis that a subsidence in one region synchronises with elevation in another at no very great distance; and, indeed, it is believed by, at least, most geologists that an instance of the kind is furnished by Sweden, which is rising along the coast of the Gulf of Bothnia, sinking in the extreme south of the peninsula, but undergoing no change in the district of which Stockholm may be regarded as the centre. Dr. Brown, however, whilst cordially accepting the evidence of upheaval in North Greenland, believes that movement to be a thing of the past, that the whole island participated in it, and that he has detected unmistakeable proofs, along the whole extent of the Danish colonies-and, in one instance, 500 feet above the sea—of a striated clay, containing shells belonging to species still living in the neighbouring sea. In like manner, he regards the subsidence now in progress as being by no means local, but shared by the entire country. He admits, however, that the district between the Danish settlements and the south coast have not been examined ; so that he can only be held to have proved that, since the advent of the species of shellfish now living in the adjacent sea, those parts of Greenland now known to be sinking were at a much lower level than they are at present; that, even then, the country was the scene of ice action, which, by depositing glacier-clay, furnished a habitat for the marine mollusks whose shells are now found in it; that after this deposition the district rose slowly above the sea, and attained a sub-ærial height of many hundred feet; that if the process of elevation resembled that in the north of the island, it was broken by protracted periods of intermittence, during which the successive terraces were formed; and that, at length, there set in a movement in the contrary direction, which is still in progress. It does not appear from the evidence at present before us that the downward movement is necessarily shared by the north, or, indeed, that the elevation has yet ceased there. On these points we need further information.

It is obvious that whilst the changes just described take us · slowly and far back into antiquity, they fail to reach the com

* “ Arctic Explorations, vol. ii. p. 81.

mencement of the glacial condition of the country. The clays, which, notwithstanding the present slow subsidence, are still 500 feet above the sea-level, were due to glacial agency, and must have been deposited when the areas in which they occur were far below the sea. They are occupied, too, by shells of the same species as now live in Greenland waters, and thus denote that the climate has not changed.

The existing ice-sheet, which so completely covers the landconcealing alike the tops of the mountains and the valleys which separate them-is eloquent of time. It represents, not the accumulated total snows of ages, but the sum of the annual surpluses-the remnants of the yearly precipitation which the conjoined actions of evaporation, ice-flow, and sub-glacial streams have failed to remove—the hoarded capital resulting from the excess of ice-income over expenditure in every form. And yet this income, is estimated at no more than ten inches annually, so that the yearly savings must have been very inconsiderable in themselves—probably an inch or two, at most. Their aggregate is vast, merely because the time of accumulation has been very protracted.

It is obvious that the geologist's chance of finding fossils is limited to the outskirting land. Here, however, and especially near Atanekerdluk, on the western coast, opposite Disco Island, in latitude 70° N.-termed North Greenland by Dr. Heer-he has been eminently successful, as has been already remarked.

From the Report of Professor Heer, it appears that the specimens collected by Mr. Whymper and Dr. Brown contained 89 species of plants, of which 20 were entirely new to science; that we are now acquainted with a total of 137 species from the same beds and localities; and that the deposits which vielded them belong to what is known to the geologist as the Viocene age-a period very remotely ancient, no doubt, when measured by even the largest unit employed in human history, but not very far back in the vast antiquity of the world. It was separated from the close of that era in which our chalk beds were formed, by a period termed the Eocene, and, in all probability, by an earlier but unrepresented interval. It was long prior, on the other hand, to the first appearance in the world of any existing species of quadrupeds, and though some of the kinds of shell-fish now living were also living then, upwards of fifty per cent. of the species forming the present molluscous fauna dite from times less ancient than those represented by the plant-beds of Atanekerdluk.

Plants of the same kind and of the same age have been found also in Iceland, and even in Spitzbergen in latitude 78° 56' N., and are wonderfully calculated to revolutionise our notions of the climate of the Arctic regions. That it cannot always have

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been frigid, is evident from the facts that of the fossils in question considerably more than half the number were trees, whilst at present no trees exist in any part of Greenland, though its southern point, Cape Farewell, is in latitude 59° 47' N., or fully 700 miles farther south than Atanekerdluk; that amongst them there were upwards of thirty different kinds of cone-bearing trees, including several species allied to the gigantic Wellingtonia at present growing in California; that the other trees were beeches, oaks, planes, poplars, maples, walnuts, limes, a magnolia, hazel, blackthorn, holly, logwood, and hawthorn; that they were not represented by leaves merely—which occurred, however, in vast profusion_but by fossil flowers and fruits, including even two cones of the magnolia, thus proving that they did not maintain a precarious existence, but ripened their fruits. Ivies and vines twined round their trunks, beneath them grew ferns having broad fronds, and with them were mingled several evergreen shrubs.

They were by no means confined to high latitudes, for at least forty-six of the species have been found as fossils in Central Europe. So far as is at present known, six of them grew no farther south than the Baltic, ten have been found in Switzerland, seven in Austria, four in France, seventeen in Italy, six in Greece, and four in Devonshire. In fact, these extinct old Miocene plants had a much wider geographical range than is enjoyed by their allies in the present day; whence Professor Heer has concluded that the temperature of the northern hemisphere, at least from Greece to within a few degrees of the Pole, was much more uniform during the Miocene era than it is at present. The mean annual temperature of North Greenland was, he believes, 30°, and of Central Europe 10°, higher than it is now.

A vegetation so luxuriant was probably the home of a large and varied amount of animal life; though, up to this time, their remains bave been but very sparingly found. Professor Heer, however, has detected two fossil insects—one of them a beetleamongst the leaves.

Such, it has been well remarked, was the variety, luxuriance, and abundance of this old Miocene flora, that if land extended at that time from Greenland to the Pole, it was probably occupied by at least many of the same species of plants.

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MHE phenomena of Jupiter during and after the opposition

1 in 1869 formed the subject of a detailed examination, the principal features of which appeared in the POPULAR SCIENCE REVIEW for April, 1870. Although no very important conclusion was deduced at that time, it seemed desirable that the observations should be continued during another opposition, as the extension of a series always possesses a certain value, whether it may be for confirmation or correction, and either change or persistency would not be without its own interest or significance. Accordingly, on Nov. 15, 1870, the planet was again brought into the same telescopic field, and the results of a scrutiny carried on through forty-nine nights, till April 15, 1871, are now laid before the public. The nomenclature originally adopted having still answered satisfactorily the purpose of identification, we shall speak, as before, of the brighter parts of the disc as the Equatoreal and Two Temperate Zones, and of the darker stripes as the Two Torrid and Two Temperate Belts, to which must be added the South Sub-torrid Belt, subdividing the South temperate zone, and the Two Polar Regions.

A comparison of the former observations with those of Mr. Gledhill, at Mr. Crossley's observatory, Halifax, and those of Professor Mayer, at Lehigh University, U.S., has brought out an unsuspected omission on my part, to which allusion ought to be made. Though my attention was especially directed to that part of the disc, I never detected the thin elliptical ring which both those eminent observers have delineated as extending in one place across nearly the whole breadth of the South temperate zone, but which, as far as I know, has escaped the notice of other astronomers.

The present series has been carried through with my silvered speculum of 9 inches, and a power of 212: as, even on those rare occasions when the air afforded sufficient sharpness for 450, there was a want of adequate light in that ocular. The atmo

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