« ПредишнаНапред »
tion of large masses of ice. In the sea south from Spitzbergen, light boats would be useless ; for it being strewed with the wreck of fields, which, from its various dispositions, acquires the name of packs, streams, or floes, the process of boring is requisite, which can be accomplished only with heavy vessels. But, in high eastern latitudes, such a process may be seldom required; and so far as these little vessels can proceed, they may traverse with tolerable freedom, rendering them the fittest means of seeking the highest northern latitude, or the greatest eastern longitude.
General Observations on the former and present Geological
Condition of the Countries discovered by Captains Party and Ross. By Professor JAMESON *.
THE observations made during the four Arctic Expeditions, viz. that under Captain Ross, and the three under Captain Parry, afford the following general facts and inferences :
1. That the regions explored abound in primitive and transition rocks; that, although the secondary rocks occupy considerable tracts, still their extent is more limited than that of the older formations; that the alluvial deposites are not extensive; that true or modern volcanic rocks were nowhere met with ; and that the only traces of the tertiary strata were found in the sandstones and clays connected with the secondary traps of Baffin's Bay.
2. That the primitive and transition islands were, in all probability, at one time connected together, and formed a continuous mass with the continental parts of America ; and that, in the plains and hollows of this land were deposited the secondary limestones, sandstones, gypsum, and coal, and upon these again the tertiary rocks.
3. That, after the deposition of these secondary and tertiary rocks, the land appears to have been broken up, and reduced either suddenly or by degrees, or partly by sudden and violent action, and partly by the long continued agency of the atmosphere and the ocean, into its present insular and peninsular form; and that, consequently, the secondary and tertiary formations were formerly, in those regions, more extensively distributed than they are at present.
* From Parry's Third Voya
4. That, previous to the deposition of the coal-formation, as that of Melville Island, the transition and primitive hills and plains supported a rich and luxuriant vegetation, principally of cryptogamous plants, especially the ferns, the prototypes of which are now met with only in the tropical regions of the earth. The fossil corals of the secondary limestones also intimate, that before, during, and after, the deposition of the coalformation, the waters of the ocean were so constituted as to support polyparia, closely resembling those of the present equatorial seas.
5. That, previous to, and during, the deposition of the tertiary strata, these now frozen regions supported forests of dicotyledonous plants, as is shewn by the fossil dicotyledonous woods met with in connection with these strata in Baffin's Bay, and by the fossil wood of Melville Island, Cape York, and Byam Martin Island.
6. That the boulders or rolled blocks met with in different quarters, and in tracts distant from their original localities, afford evidence of the passage of water across them, and at a period subsequent to the deposition of the newest solid strata, namely, those of the tertiary class.
7. That nowhere are there any discoverable traces of the agency of modern volcanoes; and we may add, that, in the Arctic Regions, the only appearances of this kind are those in Jan Mayen's Island, described by Scoresby.
8. That the only intimations of older volcanic action are those afforded by the presence of secondary trap-rocks, such as basalt, greenstone, trap-tuffa, and amygdaloid.
9. That the black bituminous coal, the coal of the oldest coalformation, which some speculators maintain to be confined to the more temperate and warmer regions of the earth, is now proved, by its discovery in Melville Island, far to the west, and in Jameson's Land, far to the east, in Old Greenland, to form an interesting and important feature in the geognostical constitution of arctic countries.
10. That the red sandstone of Possession Bay, &c, renders it probable that'rock-salt may occur in that quarter.
11. That, although no new metalliferous compounds have occurred to gratify the curiosity of the mineralogist, yet the regions explored by Captain Parry have afforded various interesting and highly useful ones, such as octahedral or magnetic ironore, rhomboidal or red iron-ore, prismatic or brown iron-ore, and prismatic chrome-ore, or chromate of iron ; also the common ore of copper, or copper pyrites ; molybdena glance, cr sulphuret of molybdena ; ore of titanium ; and that interesting and valuable mineral, graphite or black lead.
12. That the gems, the most valued and most beautiful of mineral substances, are not wanting in the Arctic Regions visited by the Expeditions, is proved by the great abundance of the precious garnet, which we doubt not will be found, on more particular examination of the primitive rocks, to present all the beautiful colours and elegant forms for which it is so much admired. Rock-crystal, another of the gems, was met with, and also beryl and zircon.
13. That these newly-discovered lands exhibit the same general geognostical arrangements as occur in all other extensive tracts of country hitherto examined by the naturalist; a fact which strengthens that opinion which maintains that the grand features of nature, in the mineral kingdom, are every where similar, and, consequently, that the same general agencies must have prevailed generally during the formation of the solid mass of the earth,
14. Lastly, That the apparent irregularities which, at first sight, present themselves to our attention, in the grand arrangements in the mineral kingdom, are the offspring of our own feeble powers of observation, and disappear when the phenomena are examined in all their relations. It is then, indeed, that the mind obtains those enduring and sublime views of the Deity, which, in geology, reward the patient observer, raise one of the most beautiful and interesting departments of natural science to its true rank, and prove that its relations connect, as it were, in the scale of magnitude, the phenomena of the earth with those more extensive arrangements presented to our intelligence in the planetary system, and in the grand frame-work of the univers, itself.
Remarks tending to explain the Geological History of the
Earth. By Professor EsMARK.*
F we carry back our investigations with regard to the structure of the earth to its original formation, we find all involved in thick darkness. There have not been wanting, however, ingenious men, who have formed theories on this subject; we find some of these even among the Greek philosophers. Among these, two opposite opinions especially prevailed ; some considered fire as the chief agent in this process; others water. Anaxarchus from Lampascus averred, that in his country the mountains had stood under water. Aristotle, Eratosthenes, Strabo, and Plutarch, supported his opinion. In later times, nobody doubts this fact, as we find petrified animals on the highest mountains. In America, such have been found on the Andes, at the height of 12,000 Rhenish feet above the level of the sea t. At first it was believed that these petrifactions were remains of the general deluge; but a more accurate investigation discovered, that they could not all be derived from this source; for, as we find on the highest mountains, and inclosed in the bowels of the earth, petrifactions of animals in every stage of their growth, and arranged in classes such as we still find alive in the sea, it may be readily inferred, that the duration of the flood was not sufficient to produce that amazing multitude of organic forms, the remains of which are now to be found in the bosom of the earth, but that these places must have once been the bottom of
In considering these petrifactions with attention, we may observe the following peculiarities among them :
1. That the greater part of these petrifactions consist of sea animals and sea plants.
It being our intention to lay before our readers, as occasion may offer, statements of the opinions on the formation of the Earth entertained by distinguished writers, we now communicate the ideas on this subject by Esmark, from the Christiania Journal.
+ Colonel Gerard found many ammonites at a height of 16,200 feet above the sea, in the Himalya range of mountains.
2. That they are not all of the same sort.
3. That they have not all been deposited at the same time, but at periods far remote from one another.
4. That those which belong to the earliest periods have a less perfect organization, the farther back the less perfect; that those on the contrary which have been found in mountains of a later formation, have a more perfectly developed organization.
5. That we find a multitude of petrifactions of different animals which are now totally extinct, and that we find others which have some resemblance to animals now existing ; but with differences which prove them to be of another species.
6. That we likewise find a great multitude of plants incorporated with the solid strata, of which some are different from those which now exist, while a great many seem to resemble them. The most remarkable circumstance connected with this fact is, that the climate of those places where these plants are found inclosed in the solid rocks, is not at all like the climate where they are now found growing. We find, for example, a multitude of plants in a state of petrifaction in the most northerly regions of Europe, which are now found growing in the torrid
As they are found with stalks and leaves, and sometimes even with fruit upon them, they must necessarily have grown
in the places where they are now found, and could not have been wafted on the surface of the sea from regions lying far distant.
7. That of the human race, we find, with certainty, no remains inclosed in the earth, with the exception of a few which have been found partly in tuffaceous limestone, partly in clefts of older mountains which have since been filled up with sand, clay, and rubbish, and which must be considered as remains of the latest revolutionary changes in the earth.
We find a variety of theories formed in later times on this sub ject, by Burnet, Whiston, Woodward, Fontanelle, De Luc, Ray, Hutton, &c. They have each their own peculiar notions ; and though it cannot be said that any one of them is right, this will be a matter of no surprise, when we consider how far behind they were in many of the sciences which have made such progress during the last century. Though from this progress in mineralogy, chemistry, physical, mathematical, and astronomical science, we stand on much higher ground than they did,