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vity of ice, and found, on immerging it in snow water, the thermometer being 34", that fourteen fifteenth parts funk under the surface of the water. It fluated in brandy just proof; and fell to the bottom at once, and immediately dissolved in rectified spirits of wine,

Soundings were obtained, under circumstances of peculiar accuracy, and in the main ocean, at the depth of fix hun. dred and eighty-three fathom: and many experiments were made in order to ascertain the temperature of the sea at different depths below the surface, some by means of lord Charles · Cavendith's thermometer, and others by a bottle of Dr. Irving's contrivance. When the heat of the air was 481, 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 mene tioned 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 surface at 55°; and in the shade, the heat of the air was 66o. These two methods, it is observed, give a different result; but the conclusions from both are very conırary to the observations of Captain Douglas near the coasts of Lapland and Norway in 1769. From his experiments, which, we formerly remarked, were “not sufficiently numerous to justify a general conclusion,” it was inferred, that the temperature gradually increased, as the thermometer was sunk to greater depths. See Phil. Tranf. vol. 60. and Monthly Rev. vol. 46. p. 182. The temperature of the sea was likewise tried, when agitated by a very hard gale of wind; the thermometer plunged into a wave of the sea rose from 50°, its height in the air, to 62o : Dr. Irving, by this experiment, has confirmed an observation of Plutarch in his natural quesa tions, “ that the sea becomes warmer by being agitated in waves.”

The next article contains the observations that were made on the island of Spitsbergen, for ascertaining the height of a mountain : those by the barometer were under the care of Dr. Irving, while Captain Phipps was employed in determining it geometrically. By the sea side the barometer stood at 30,040 inches and the thermometer at 50°; on the summit of the mountain, the barometer was at 28,266 inches, and the thermonieter 42°: about an hour later at the same place, the former was at 28,258, and the latter at 42°; by the sea fide, the barometer was 30,032 inches and the ihermometer at 44'. M. de Luc calculated the height of the mountain from the fift observation 1585 feet, and from the second 1592 feet : 10 that the mean height is 1588{ feet. But by geometrical measurement it was found to be only 1503, 5 feet less by 84, 7 feet Rev. Feb. 1775.

than

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

The observations on the pendulum, though not so complete and perfect as the astronomer might wish, are nevertheless acceptable and interesting. They are recited with great fairness and 'impartiality; so that persons skilled in astronomical calcula. tions have an opportunity of tracing and examining for them. selves every step towards the conclusion, and by, that means be enabled to detect any error that may have crept into the operation ; or draw such further conclusions as their ingenuity may fuggelt, and the materials here given may warrant.' We 'fhall endeavour to Thew in a subsequent article wherein they 'fail : and for the sake of brevity fhall only give the general sesult as it is here stated. A pendulum (says Captain Phipps) which vibrates seconds at London, will gain from seventy-two to seventy-three seconds in the twenty-four hours, in latitude 77° 50'; allowing the temperature of the air to be the same in both places. These observations give a figure of the earth nearer to Sir Isaac Newton's computation than any others which have hitherto been made. According to Sir Isaac Newton the pen

dulum gains in latitude 790 56 - 66", 9;
'In which case the equatorial diameter
· would be to the polar as - - . 230 to 229:
According to Mr. Bradley's computation,

from Mr. Campbell's observations – 76, 6;
Equatorial diameter to the polar as - - 201 to 2co:
According to Maupertuis, - 86, 5;
Equatorial diameter to the polar as - - 178 to 179:
According to my observations - $72, 20

. 273, 06; Equatorial diameter to the polar as

S212,9 to 211,9

210,7 to 209,7: The mean of which is very nearly as .. 212 to 211.

In the catalogue of natural productions, the Reader may find several specimens of plants and animals, some of which are little known, and others, never before described. . But we must hasten to terminate this article, already too far prolonged, with a brief account of Dr. Irving's contrivance for obtaining fresh water from the sea by distillation *. In his method, no foreign ingredients are made use 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 subject to the inconveniences and difficulties

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

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June 20th water froms of its utilicendi

of Dr. Lind's method, nor to those of Mr. Hoffman's, first at. tempted in the year 1765, and of others, practifed about the fame time. Nothing is required but a simple tube, which is easily made, even at sea, and applied to the ship's kettle or boiler. This tube is to be fitted close to the top of the boiler, and placed in an horizontal direction, in order to prevent any compression of the Auid ; and by means of a mop, paffed along its upper surface, to be kept constantly wet. We must refer to his own account for the farther improvements of this practicable and useful contrivance; and conclude with Cap. tain Phipps's recital of the advantages attending it.

* We began this day (June 20th) to make use of Dr. Ir. ving's apparatus for distilling fresh water from the sea: repeared trials gave us the most satisfactory proof of its utility : the water produced from it was perfectly free from salt, and wholesome; being used for boiling the ship's provisions; which convenience would alone be a desirable object in all voyages, independent of the benefit of so useful a resource in care of dira ftress for water. .. The quantity produced every day varied from accidental circumstances, but was generally from thirty-four to forty gallons, without any great addition of fuel. T'wice indeed, the quantity produced was only twenty-three gallons on each dirtillation ; this amounts to more than a quart for each man, which, though not a plentiful allowance, is much more than what is necessary for subsistence. In cases of real necessity I have no reason to doubt that a much greater quantity might be produced without an inconvenient expence of fuel.'

The last article in the appendix is an account of the astronomical observations and time-keepers *, by Mr. Lyons ; who, for this purpose, embarked in the voyage, by appointment of the Board of Longitude. .

• For Remarks on this part of the work, our Readers are referred to the next ensuing article.

R...8. AST. VIII. Remarks on the Observations made in the late Voyage

towards the North Pole, for determining the Acceleration of the Pendulum, in Latitude 79° go'. By Samuel Horsey, LL. D. Sec. R. S. In a Letter to the Hon. Constantine John Phipps. 410. 15. White. 1774.

R. Horsley, in this publication, has detected two errors in

the calculations of Mrs Ifrael Lyons relating to the gaia of the pendulum recited in the foregoing article : which, per haps, were owing more to hurry and negligence (for either of which, however, we do not conceive what any cxcule can be urged, that will prove satisfactory to the Public) than to the Want of fufficient mathematical knowledge. To whatever caufe K2

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the intelligent and candid may ascribe them, it is proper to observe, in this place, that Captain Phipps is no otherwise accountable for them than by suffering them to pass, unexamined and uncorrected. They do not, however, immediately affect the truth of the general observation; but reduce the evidence of the acceleration of the pendulum to the comparison with the watch, and the fix altitudes of the sun taken with the astronomical quadrant for determining the loss of the watch The farther confirmation of this aftronomical delia deratum deduced from the observation of the sun's return to the vertical wire of the equatorial telescope, is clearly evinced to be “ imaginary,” and to arise merely from an error in the computation.

As to the ultimate conclusion that these observations give a · figure of the earth nearer to Sir Isaac Newton's computation, than any others which have hitherto been made' (see the preceding article), Dr. Horsley's reasoning seems materially to affect it. If (lays he) the meridians be ellipses, or, if the fie gure of the earth be that of a spheroid generated by the revolution of an ellipfis, turning on its shorter axis, the parti, cular figure, or the ellipticity of the generating ellipsis, which your observations give, is nearer to what Sir Isaac Newton faith it should be, if the globe were homogeneous, than any that can be derived from former observations. But yet it is not what you imagine. Taking the gain of the pendulum in latitude 79° 50' exactly as you state it, the difference between the equatorial and the polar diameter, is about as much less than the Newtonian computation makes it, and the hypothesis of homogeneity would require, as you reckon it to be greater. The proportion of 212 to 211 should indeed, according to your observations, be the proportion of the force that acts upon the pendulum at the poles, to the force acting upon it at the equator. But this is by no means the same with the propor

tion of_the equatorial diameter to the polar. If the globe were , 'bomogeous, the equatorial diameter would exceed the polar by is of the length of the latter : and the polar force would also exceed the equatorial by the like part. But if the difference between the polar and equatorial force be greater than ajo, (which may be the case in an heterogeneous globe, and seems to be the case in ours,) then the difference of the diameters should, according to theory, be less than zzó, and vice versa..

In consequence of this reasoning, and by means of a theorem, demonstrated by Moni. Clairault, in his treatise on the Figure of the Earth, Dr. H. determined the ellipticity of the earth's figure, according to the observations of the pendulum now published, to be ašī. This, he says, is the true conclusion on the supposition, that the ineridians are ellipses : a supposition,

though

though it is the foundation of the present theory, the truth of which, he thinks, may be questioned from experiment. Ac. cording to this hypothesis, the increment of the force which actuates the pendulum, as we approach the poles, should be as the square of the fine of the latitude; or which is the same thing, the decrement, as we approach the equator, should be as the square of the cofine of the latitude.' But, Dr. H. apprehends, that observations of the pendulum in different la. citudes, several of which are here subjoined, do not establish this proportion. If the meridians are not ellipses, the difference of the diameters may indeed, or it may not, be proportional to the difference between the polar and the equatorial force ; but it is quite an uncertainiy, what relation subsists between the one quantity and the other ; our whole theory, except so far as it relates to the homogeneous spheroid, is built upon false assumptions, and there is no saying, what figure of the earth any observations of the pendulum give.'

This pamphlet ought to be annexed to every copy of Cape tain Phipps's book, and bound up with it.

..s

ART. IX. Moral Discourses on Providence, &c. By Thomas Hunter,

M. A. Vicar of Weaverham in Cheihire. 8vo. 2 vols. 125. fewed. Warrington, printed. Sold by Cadell in London. 1774. T HE first volume of these sermons is entirely devoted to

l the proof of a superintending providence, and a vindication of the methods of the divine government. The great aim of the preacher is to manifest the righteousness of providence in humbling the proud, punishing the luxurious, and ordaining ftates and kingdoms to rise or fall according to the degree in which virtue or vice prevailed among them; occasionally endeavouring to illustrate and support his assertions, by instances drawn from ancient and modern history.

• We cannot, says Mr. Hunter, speaking of the state of nations, the fall of states and empires, close the page of ancient eastern story, without casting a mournful eye on the broken, yet elegant remains of PalmyraAt the first fight, or mere representation of these ruins, as they are exhibited to us by the curious travellers, their magnis ficence and elegance ftrike you with a pleasing wonder, which is immediately succeeded, at least I found it so, with a deep sensibility of the uncertainty of human greatness, and the awful process of a divine providence, in thus humbling the efforts of human pride. In this scene of desolation, I thought there appeared visibly the hand of Heaven. The ravage of an enemy rarely makes such universal rain, or extends to the laboured demolition of every monument of art, especially where the materials are so hard and durable, and no advantage accrues to the ravager. The city might have been difmantled upon policy; but it could serve no interests to tear its bowels, and rend it as it were piece-meal, and limb from limb. K 3

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