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in his Journal for January, 1869, to publish a map illustrative of all the researches which have been made in the Polar sea, entering at Behring's straits, from the days of the Russian Deshnew, in 1648, the Danish Behring in 1729, and the English Capt. Cook in 1778, to those of our countryman, Capt. Long, in the summer before last.

This historical survey concludes with some remarks, a sketch of which may interest some of our American readers. The history of discoveries in the Polar sea within Behring's straits is instructive in reference to the question, of what use will the Polar sea ever be ? and why these repeated expeditions ? So far as yet explored, it is a very limited portion of the ocean, far distant from Europe, known to the Russians for more than two hundred years and yet to them of scarcely any use. But the enterprising Americans have shown what can come from such a sea of ice. Capt. Roys, first of the American whalers, visited this sea in the summer of 1848; he crossed from continent to continent as far as 72° N. lat., saw no ice, but many whales, which were unusually fearless and easily captured; and during the season he had such good weather that the seamen wore light clothing. In consequence of his successful cruise, the next year not less than 154 American vessels manned by 4650 sailors went to Behring's straits and had great success in whale fishery, their captures in two years being valued at $8,442,453.

For twenty years the business has been prosecuted in that region with increasing energy, and, notwithstanding the captures which have been made, it continues to yield important results.

To these remarks the writer adds an exaggerated report of the value of American whale fisheries. We are enabled on good authority to say that whales have diminished in the Arctic seas as in all other fields, and the fleet is consequently reduced. There will not be more than forty vessels in the Arctic during the coming summer.

On the other hand, it is reported that from St. Paul's and St. George's islands, in Behring's sea, south of the straits (part of the Alaska purchase), 200,000 fur seals were captured during the year 1868, valued at about $1,000,000.

An independent treatise on the Arctic fisheries of the German ports is soon to be published as one of the supplements of Petermann's Journal. SOUNDINGS AND TEMPERATURES IN THE GULF STREAM, BY Com

MANDER CHIMMO, R. N. Comm. Chimmo, R. N., in H. M. S. Gannet, was ordered on a homeward voyage, last year, to define the northern limits of the Gulf Stream, and to take deep soundings and temperatures within those limits. From his communication to the Royal Geographical Society, we gather the following facts. He sailed from Halifax, July 1, 1868.

1. Lat. 43° 20', long. 60°W., 30 miles south of Sable Island, a sounding was obtained of 2600 fathoms, or 15,600 feet, nearly 3 miles; with a weight of 232 lbs. and Brooke's apparatus, the rod brought up, after four hours patient hauling, foraminiferæ, in their various forms, chiefly globigerinæ, the interior of those fully developed being coated with fine quartzose sand.

2. West edge of the Grand Banks. A sounding of 1500 fathoms, 9000 feet, brought up quartzose sand, with globular forms of calcareous formation, and some algæ with parasitical attachments. The temperature of this mud or ooze was 56°; but at 1000 fathoms the thermometer showed 40° 3', and at 500 fathoms only 39° 5', the sea surface being 60°.

3. Having run north of the limit of the Gulf Stream, he stood to the southward, and at a depth of 1500 fathoms the cup brought up the usual gray impalpable mud or ooze. Temperature at surface 65°, and at 100 fathoms 15°.

4. Thirty miles south of the Grand Bank, where the deepest waters of the Atlantic were supposed to be, the same ooze was found at a depth of 1450 fathoms, disproving the idea of the deepest water being here. The same stratum of cold arctic water was here passing under the warmer waters of the Gulf Stream. The rod brought up a piece of feldspar, with particles of mica, evidently deposited by icebergs from Davis' Siraits, and that very recently.

5. Lat, 42° 37' N., and long. 41° 45' W.; 4300 fathoms of line were run out, and no bottom reached.

6. Lat. 43° 30' N., long. 38° 50', where “Milne Bank” is located. From a depth of 2280 fathoms, 13,680 ft., the rod brought up ooze abounding in animal, vegetable and mineral substances. The temperatures were as follows; air 77o, sea-surface 73, 100 fathoms below, 62°, 300 fathoms below, 55°, and at 1000 fathoms below, 42 Going north again to the Polar waters, the surface temperature changed in 2, hours from 72° to 58o.

7. Lat. 46°, 25 miles from the edge of the bank, a sounding of 1000 fathoms brought up large quantities of rounded quartz, of various colors. Here a section was made of the slope of the bank, showing its ascent, formation, etc., from 1000 fathoms, of colored quartzose sand; to 650, of siliceous spicules of sponges ; 450, green mud ; 150, quartzose sand ; 60, stones ; 55, stones, sand and fishbones.

8. Lat. 44° 3' N., long. 48° 7' W., a sounding of 1650 fathoms brought up foraminiferæ, spicules of sponge, and coccoliths. Temperature, 1000 fathoms, 39° 5'; 50 fathoms, 43°; surface, 61°

9. A second sounding on “Milne Bank,” still revealed no bank. In lat. 43° 40', long. 38° 50', the lead reached 2700 fathoms, and the rod brought up a small particle of foraminifera.

10. Lat. 43° 30' N., long. 38° 5' W., sounding of 2000 fathoms, bringing up foraminiferæ and a piece of stone.

11. Lat. 43° 43' N., long. 37° 47' W. ; a sounding of 1930 fathoms brought up foraminiferæ. Temperatures, 2000 fathoms, 42° ; 1000 fathoms, 43'; 400 fathoms, 49° ; 100 fathoms, 59°; sea surface, 69' ; air, 68o.

12. Lat. 43° 39' N., long. 36° 46' W. A sounding of 2600 fathoms, bringing up foraminiferæ, etc.

13. Lat. 46° N., long. 29° 40' W. A sounding of 1650 fathoms brought up foraminiferæ and diatomaceæ surrounding six dead hyalæa shells.

14. Lat. 47° 11' N., long. 23° 14'. A sounding reached the bottom at 2000 fathoms; temperature 42'.

In this sounding were many globigerinæ.

These various soundings, varying in depth from 80 to 2700 fathoms, in an area of above 10,000 square miles, from Sable Island to the Azores, show a remarkable uniformity both of temperature and sea bottom. In all the organized forms discovered, says Lieut. Chimmo, no life was perceptible, except in two doubtful instances. “Therefore,” he concludes, “these minute creatures do not live where found at the bottom of the ocean.” This remark was questioned, after the reading of the paper, by Prof. Huxley, who spoke as follows:

“With regard to the deep-sea soundings which Lieutenant Chimmo had described, speaking with every respect for the zeal and high intelligence which that gentleman had displayed in his observations, and knowing practically how difficult it was to make such observations while at sea, he still might be permitted to remark that they made no substantial addition to what had already been establishsd by a considerable number of observers, with regard to the character of the Atlantic sea bottom. In some respects he ventured to think-having been favored by the Hydrographer to the Admiralty with the particular soundings that Lieutenant Chimmo had brought home-that he had not quite clearly interpreted the facts. There could be no doubt that animal remains were contained in a very large proportion of the Globigerine shells. By proper methods of treatment, by dissolving them in acids, you may get out the soft bodies. Not only so, but Professor Frankland, to whom he had submitted portions of such soundings, had determined, by the processes of organic analysis, the existence of more than 10 per cent of organic matter in these soundings ; which 1} per cent of organic matter could be

clearly identified by the microscope in two shapes : in part as Globigerina shells, in part as a confused network of simple organisms, distinct from the Globigerina-one of the most remarkable of simple organisms, to which he had given the name of Bathybius. That simple organismone of the simplest forms of animal life--we now know covered the whole area of the North Atlantic in all the regions that had yet been surveyed. The very admirable soundings in the Indian Ocean, which had been made by Captain Shortland, to which Captain Sherard Osborn referred, bad enabled him to extend his knowledge of that organism. From the Arabian Gulf, at a depth of 2800 fathoms, along the whole of the east coast of Africa, round the Cape of Good Hope, and along the west coast until it joined the North Atlantic again, he could trace throughout the whole extent, at these prodigious depths, that that seabottom was covered with a network of organic matter. There could be no sort of doubt that living animals exist at the bottom of the deepest seas yet explored. How they lived there, how they acquired their store of food, was one of the most curious questions of organic chemistry; one which we could not solve at present. But it was the fact that there were two distinct constituents in this Atlantic mud: one of them like the organisms which he had described and the Globigerina living on the sea-bottom, and the other siliceous remains of organisms living near the surface, and which only reached the bottom after they died, for their skeletons had sunk down through the great depth of sea-water and mixed with the living creatures at the bottom. He looked upon those two results as now definitely acquired to science. He might remark, perhaps, in reference to something which was let fall by Captain Osborn, that, as far as he had been able to examine the deep-sea soundings from the Arabian Gulf, the character of the bottom was, in the main, very similar to that of the great Atlantic plateau. Over most parts of it the sticky, adhesive Globigerina mud exists in large proportion, and in certain parts Globigerinæ are replaced by an excessively fine and attenuated sand. But in all the specimens which had been brought up by Lieut. Chimmo, there was an entire absence of every thing but the very finest and softest calcareous or siliceous matter."

HIGHEST PEAKS OF THE CAUCASUS. Readers of a recent article on the Caucasus, in this Journal, by Capt. v. Koschkull, may be interested in having their attention called to a capital map of that mountain range, which is given in Petermann's Mittheilungen, ii, 1869. The accompanying notes give the following as the elevations of the four most important peaks of the proper or Great Caucasus : Elbruz,

18,572 Eng. feet, 17,426 Paris feet. Koschan-tau, 17,123

16,066 Dych-tau, 16,928

15,883 Kasbek, 16,546

15,525 The Ararat is almost equally high with the Dych-tau, viz : 16,916 Eng. feet, or 15,872 Paris feet.

GEODETIC MEASUREMENTS IN EUROPE. There is a good prospect that at an early day, the measurements of an arc of meridian, undertaken by the Russian government, will be extended into the Turkish dominions, and possibly into the island of Crete. If the project is carried out, an arc of 35° 35' will have been measured, extending from 35° 5' to 70° 40' N. lat., the utmost possible in Europe. A measurement of the 52d parallel, between Valentia on the Irish Coast and Orsk on the Kirgisen Steppe, has lately been completed.-Petermann, ii, 1869.

ART. XXXVIII. - The Cohahuila Meteoric Irons of 1868,

Mexico; by J. LAWRENCE Smith, Louisville, Ky.

The region of Mexico bordering on Texas seems to have been most profusely furnished with

these celestial visitors. In 1854 I first drew the attention of the scientific public to the meteoric irons of this region, at which time I described one brought from there by Lieut. Gouch, referring at the same time to one mentioned by Mr. Weidner near the southwestern edge of the Balsin de Mapini, on the route to the mines of Panal, weighing not less than one ton; also to another mentioned by Dr. Berlandier, in his journal of the commission of limits, that at the Hacienda of Venagas there was (1827) a piece of iron that would make a cylinder one yard in length with a diameter of ten inches. It was said to have been from the mountains near the Hacienda (see my article on the subject, this Journal, 1854). In the description there given it was stated that the specimen examined came from 60 miles north of Santa Rosa, and therefore in one or two collections in which it is to be found it is called incorrectly Santa Rosa meteorite. I was allowed to cut off but a small piece of it from the original specimen, which is in the Smithsonian Institution, and consequently I was able to supply but two or three specimens. For the discovery and collection of the specimens now under consideration we are indebted to Dr. H. B. Butcher, and I will give a full detail of the discovery as communicated in letters to his father by Dr. Butcher, to whom the scientific world are certainly indebted for the labor, expense, and danger incurred in procuring them. I must not, however, fail to state that I am indebted to Dr. Feuchtwanger for first informing me of the fact of their arrival in this country, and for the exhibition of a small fragment to the members of the American Scientific Association at Chicago in 1868.

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