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ing on the mofs; one we killed, and found it fat and of high flavour. We faw a light grey-coloured fox; and a creature fomewhat larger than a weazel with fhort ears, long tail, and fkin fpotted white and black. The island abounds with fmall fnipes, fimilar to the jack-fnipe in England. The ducks were now hatching their eggs and many wild geefe feeding by the water fide.' In their return from reconnoitering this island, they wounded a fea-horfe, which dived and brought up with it a number of others. Thefe joined in an attack upon the boat, wrested the oar from one of the men, and had like to have overfet her: but on the arrival of another boat, they difperfed. A fimilar attack they had before met with off Moffen ifland. On the 30th, being in lat. 80° 31′ and long. 18° 48′′ E. they were inclosed by the ice; and nothing could be feen from the highest eminence but one continued plain of smooth unbroken ice, bounded only by the horizon: they also faw land ftretching to the S. E. laid down in the Dutch charts, as islands. The main body of ice (before traced from W. to E.) they now perceived to join to thefe iflands, and from them to what is called the North Eaft Land. In returning, the ice having closed much fince they went, they were frequently forced to haul the boat over it to other openings. The weather exceedingly fine and mild, and unusually clear. The scene was beautiful and picturesque; the two fhips becalmed in a large bay, with three apparent openings between the islands which formed it, but every where furrounded with ice as far as we could fee, with fome ftreams of water; not a breath of air; the water perfectly smooth; the ice covered with fnow, low. and even, except a few broken pieces near the edges: the pools of water in the middle of the pieces were frozen over with young ice. The field of ice to which they moored the hips was eight yards ten inches thick at one end, and seven yards eleven inches at the other. Having remained in this alarming fituation for feveral days, and every effort to difengage themfelves proving fruitless, the Captain determined to fit out the boats for their return, and on the morning of the 7th of Auguft fet out with the launch over the ice; but at the fame time every precaution was used to release the fhips. The boats were hauled about 5 miles over the ice. They were, however, on the 9th agreeably furprised to find that the hips had driven much more than they expected: and the wind springing up to the N. N. E. the morning of the 10th they crowded fail and forced their way through the heavy ice into the open fea: and on the 11th they came to anchor in the harbour of Smeerenberg, on the coaft of Spitsbergen. They continued here till the 19th; and finding it impoffible to proceed to the northward, they made the best of their way home.

During their stay on the coaft of Spitsbergen, they had an opportunity of particularly obferving one of the moft remarkable icebergs which are to be met with in this northern latitude. Icebergs are large bodies of ice filling the vallies between the high mountains, the face towards the fea is nearly perpendicular, and of a very lively light green colour.' An engraving of one of them is annexed *. It was about three hundred feet high, with a cafcade of water iffuing out of it. The black mountains, white fnow, and beautiful colour of the ice make a very romantick and uncommon picture. Large pieces frequently break off from the icebergs, and fall with great noife into the water: we observed one piece which had floated out into the bay, and grounded in twenty-four fathom; it was fifty feet high above the furface of the water, and of the fame beautiful colour as the iceberg.'

Capt. Phipps clofes his account of this country with fome general obfervations, from which we fhall only extract the following: The stone we found was chiefly a kind of marble, which diffolved eafily in the marine acid. We perceived no marks of minerals of any kind, nor the leaft appearance of present, or remains of former, volcanos. Neither did we meet with infects, or any fpecies of reptiles; not even the common earth-worm. We faw no fprings or rivers, the water, which we found in great plenty, being all produced by the melting of the fnow from the mountains. During the whole time we were in these latitudes, there was no thunder or lightning.'

Neither the nature of our publication nor the limits to which we are neceffarily confined will allow us to be very minute in recording the experiments, which were made, in the course of this voyage. To give our Readers a juft idea of the whole procefs by which they were conducted would oblige us to trefpafs too much on other articles, more generally entertaining. We must therefore content ourselves, for the most part, with the final refult.

Captain Phipps has taken great pains to render a voyage, neceffarily barren of amufing incidents, inftructive and interesting. The practical navigator, the aftronomer, and the naturalift, will derive much information from the perufal of the Appendix to this work. The first article contains obfervations on the various methods of measuring a fhip's way. As the captain failed nearly on a meridian, he had a favourable opportunity of making experiments on different logs, and of particularly afcertaining the utility of a late improvement of this nautical inftru

The whole work is richly embellished with copper-plates.

ment

ment by M. Bouguer; an account of which may be seen in the Memoirs of the Academy of Sciences for the Year 1747 and he recommends it, upon the whole, as preferable to that in common ufe. The Megameter, defcribed by M. de la Charniere, and as yet but little known, was usefully applied, in the course of this voyage, to the purposes of marine furveying: the obfervations made with this inftrument form the fecond article of the Appendix. Captain Phipps concludes, from a feries of very accurate obfervations on the variation, that near the latitude of 80', if it alters at all with time, it does not alter in any degree as it does in these latitudes.' If Fotherby's were taken with a compafs in which a correction was made for the variation at London, his obfervation agrees exactly with thofe made by me in Vogel Sang and Smeerenberg: and thofe of Poole and Baffin differ fo little from mine, that the difference need not be regarded. But the variation in London now differs from what it was at that time above twenty-fix degrees.' He infers likewife, that in going to the eastward in the latitude of 80°, the wefterly variation decreafes very confiderably from a difference in the longitude.' It appears, moreover, from very accurate obfervations on the dip of the needle, that it increases in going north: nor does Captain Phipps apprehend, that the dip is fubject to any variation in the fame place at different periods of time. The following extract from the annexed table may amuse the curiofity of fome of our Readers. Lat. 51 35 Mean dip 73° 31′ Lat. 60° 18′ Mean dip 75° Lat. 78° 2 Mean dip 80° 25′ Lat. 80° 12′ Mean dip 81° 52′ Lat. 80° 27′ Mean dip 82° 2.

The meteorological obfervations make the next article. Under the head of mifcellaneous experiments, we find that the bferved refraction in the latitude of Smeerenberg answered within a few feconds to the calculation in Dr. Bradley's table; whence it may be reafonably prefumed, that the refrac tions in the higher latitudes follow the fame law as in thefe. Dr. Irving made an experiment to determine the specific gra

*The inftruments made ufe of in keeping the meteorological journal were, a marine barometer, prepared by Mr. Nairne; Mr. De Luc's new hygrometer; and a manometer, conftructed by Mr. Ramfden for this voyage. This laft inftrument is of a new contrivance for afcertaining the differences in the denfity of the air, arifing from the changes in its weight and heat: but as it is yet in a state of acknowledged imperfection, we fhall, for the prefent, omit any farther account of it. Captain Phipps, however, imagines, that by future improvement it may be rendered of great ufe in determining refractions for aftronomical obfervations, and for indicating an approaching gale of wind at sea.

vity of ice, and found, on immerging it in fnow water, the thermometer being 34°, that fourteen fifteenth parts funk under the furface of the water. It floated in brandy juft proof; and fell to the bottom at once, and immediately diffolved in rectified fpirits of wine.

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Soundings were obtained, under circumftances of peculiar accuracy, and in the main ocean, at the depth of fix hundred and eighty-three fathom: and many experiments were made in order to ascertain the temperature of the fea at different depths below the furface, fome by means of lord Charles Cavendish's thermometer, and others by a bottle of Dr. Irving's contrivance. When the heat of the air was 48°, that of the water at the depth of 780 fathom was 26°; in another trial, the heat of the air being 59°, that of the water 673 fathom deep was only 32° and in the founding before mentioned of 683 fathom a thermometer plunged into the water raised (by means of Dr. Irving's bottle) from the bottom stood at 40°; in water from the furface at 55°; and in the shade, the heat of the air was 66°. These two methods, it is obferved, give a different refult; but the conclufions from both are very contrary to the obfervations of Captain Douglas near the coafts of Lapland and Norway in 1769. From his experiments, which, we formerly remarked, were "not fufficiently numerous to justify a general conclufion," it was inferred, that the temperature gradually increafed, as the thermometer was funk to greater depths. See Phil. Tranf. vol. 60. and Monthly Rev. vol. 46. p. 182. The temperature of the fea was likewife tried, when agitated by a very hard gale of wind; the thermometer plunged into a wave of the fea rofe from 50°, its height in the air, to 62°: Dr. Irving, by this experiment, has confirmed an obfervation of Plutarch in his natural queftions, "that the fea becomes warmer by being agitated in waves."

The next article contains the obfervations that were made on the island of Spitsbergen, for afcertaining the height of a mountain: thofe by the barometer were under the care of Dr. Irving, while Captain Phipps was employed in determining it geometrically. By the fea fide the barometer ftood at 30,040 inches and the thermometer at 50°; on the fummit of the mountain, the barometer was at 28,266 inches, and the thermonieter 42° about an hour later at the fame place, the former was at 28,258, and the latter at 42°; by the sea fide, the barometer was 30,032 inches and the thermometer at 44°. M. de Luc calculated the height of the mountain from the hift observation 1585 feet, and from the fecond 1592 feet: to that the mean height is 1588 feet. But by geometrical measurement it was found to be only 1503, 5 feet lefs by 84, 7 feet REV. Feb. 1775.

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than

than the barometrical altitude: A difference which Capt. Phipps is at a lofs to account for.

. The observations on the pendulum, though not fo complete and perfect as the aftronomer might wish, are nevertheless acceptable and interefting. They are recited with great fairness and impartiality; fo that perfons fkilled in aftronomical calcula tions have an opportunity of tracing and examining for themfelves every step towards the conclufion, and by, that means be enabled to detect any error that may have crept into the operation; or draw fuch further conclufions as their ingenuity may fuggeft, and the materials here given may warrant.' We fhall endeavour to fhew in a fubfequent article wherein they fail and for the fake of brevity fhall only give the general refult as it is here ftated. A pendulum (fays Captain Phipps) which vibrates feconds at London, will gain from seventy-two to feventy-three feconds in the twenty-four hours, in latitude 77° 50; allowing the temperature of the air to be the fame in both places. Thefe obfervations give a figure of the earth nearer to Sir Ifaac Newton's computation than any others which have hitherto been made.

According to Sir Ifaac Newton the pen

dulum gains in latitude 79° 50' In which cafe the equatorial diameter would be to the polar as

According to Mr. Bradley's computation,

from Mr. Campbell's obfervations Equatorial diameter to the polar as According to Maupertuis,

66", 9;

230 to 229:

76, 6;

201 to 200:

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Equatorial diameter to the polar as

According to my obfervations

Equatorial diameter to the polar as

The mean of which is very nearly as

$72,

178 to 179:

212 to 21I.

In the catalogue of natural productions, the Reader may find feveral fpecimens of plants and animals, fome of which are little known, and others, never before defcribed.

But we must haften to terminate this article, already too far prolonged, with a brief account of Dr. Irving's contrivance for obtaining fresh water from the fea by diftillation *. In his method, no foreign ingredients are made ufe of; neither "the Lapis infernalis and calcined bones of Mr. Appleby, nor the foap leys of Dr. Butler, nor the 'powdered chalk of Dr. Hales; nor is it fubject to the inconveniences and difficulties

See Dr. Lind's impeachment of Dr. Irving's method, Rev. for August, 1774, p. 160..

of

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