no firft chapters in Genefis, it pleafing the all-wife Difpofer to remove him to that glorious ftate, where all he had been meditating upon in this imperfect one, was doubt opened to his view. It is impoffible to defcribe the heartfelt delight he received in ftudying the holy fcriptures; and his mind was fo illumined with these facred truths, and with holding as he did a conftant intercourse with the Divine Nature, that he feemed to be above the injuries of fortune, or pains of fickness, looking forwards to a more permanent condition. His fublime piety, virtue, amiable and cheerful difpofition, made him equally be loved and refpected; nor was ever any man more warmly and tenderly attached to his friends than he was. Mr. Welt had too much dignity of character to admit of pride or fupercilioufnefs; never beholding with fcorn the imperfect characters, or imperfect pleafures of other men, he enjoyed with complacency, himself, the innocent pleafures of life, whether prefented to him under the form of beautiful nature or ingenious prefent Majesty. This being com- art. To an early friendship with the then Duke of Devonthire's fon, he owed the being appointed one of the clerks extraordinary of the privy council, the duke being prefident; and to Mr. Pitt, afterwares Lord Chatham, he was indebted for his being treasurer of Chelfea Hofpital. But as the advantages flowing from them to him very late in life, he may be faid to have paffed almost through it with a narrow income. His mind however being rich with knowledge knowledge and content, he might be deemed, notwithstanding his claim to a high fituation, a happy man until he loft his only child, a fon at man's eftate, in whom he had placed much comfort and all his hopes. On receiving the fatal fhock of his death, he only emphatically faid, "My dear fon is taken to a better Father;" and with that pious reflection, he calmed his own forróws and thofe of his afflicted wife and fympathizing friends. He furvived his fon but one year, and died in 1756, aged about fifty. NATURAL NATURAL HISTORY. On the Heat of the Water in the actions. ONE of the most remarkable facts obferved in navigating the ocean, is that conftant and rapid current which fets along the coat of North America to the northward and eastward, and is commonly known to feamen by the name of the Gulf-ftream. It feems juftly attributed to the ef fect of the trade-winds, which blowing from the eastern quarter into the great Gulf of Mexico, cause there an accumulation of the water above the common level of the fea; in confequence of which, it is constantly running out by the channel where it finds leaft refiftance, that is, through the Gulf of Florida, with fuch force as to continue a distinct ftream to a very great diftance. Since all fhips going from Europe to any of the fouthern provinces of North America muft crofs this current, and are materially affected by it in their courfe, every circumftance of its motion becomes an object highly interefting to the feaman, as well as of great curiofity to the philofopher. An observation which occurred to me on the fpot fuggefts a new method of inveftigating a matter that appears fo worthy of attention. During a voyage to America in the fpring of the year 1776, I ufed frequently to examine the heat of fea-water newly drawn, in order to compare it with that of the air. We made our paffage far to the fouthward. In this fituation, the greatest heat of the water which I obferved was such as raised the quickfilver in Fahrenheit's thermometer to 77°. This happened twice; the first time on the 10th of April, in latitude 219 10 N. and longitude, by our reckoning, 52° W.; and the fecond time, three days afterwards, in latitude 22° 7′ and longitude 55°; but in general the heat of the fea near the tropic of Cancer about the middle of April, was from 76° to 77°. The rendezvous appointed for the fleet being off Cape Fear, our courfe, on approaching the American coaft, became north-westward. On the 23d of April the heat of the fea was 74°, our lati From the difference between civil and nautical time, it becomes neceffary to obferve, that the former is always meant in this paper. tude tude at noon 28° 7′ N. Next day the heat was only 71°; we were then in latitude 29° 12′; the heat of the water, therefore, was now leffening very fast in proportion to the change of latitude. The 25th our latitude was 31° 3′; but though we had thus gone almoft 2° farther to the northward, the heat of the fea was this day rather increased, it being 72° in the morn. ing, and 72° in the evening. Next day, the 26th of April, at half after eight in the morning, I again plunged the thermometer into fea-water, and was greatly furprised to fee the quickfilver rife to 75°, higher than I had ever obferved it, even within the tropic. As the difference was too great to be imputed to any accidental variation, I immediately conceived that we must have come into the Gulf-ftream, the water of which fill retained great part of the heat that it had acquired in the torrid zone. This idea was confirmed by the fubfequent reguBar and quick diminution of the heat; the ship's run for a quarter of an hour had leffened it 2°; the thermometer, at three quarters after eight, being raised by feawater fresh drawn only to 76°; by nine the heat was reduced to 73°, and in a quarter of an hour more, to 71° nearly all this time the wind blew frefl, and we were going feven knots an hour on a north-western courfe. The water now began to lofe the fine tranfparent blue colour of the ocean, and to affume fomething of a greenifh olive tinge, a well-known indication of foundings. Accordingly, between four and five in the afternoon, ground was ftruck with the lead at the depth of : eighty fathoms, the heat of the fea being then reduced to 69o. In the course of the following night and next day, as we came into fhallower water and nearer the land, the temperature of the fea gradually funk to 65°, which was nearly that of the air at the time. Unfortunately, bad weather on the 26th prevented us from taking an obfervation of the fun; but on the 27th, though it was then clou dy at noon, we calculated the la titude from two altitudes, and found it to be 33° 26' N. The difference of this latitude from that which we had obferved on the 25th, being 2° 23', was fo much greater than could be deduced from the fhip's run marked in the log-book, as to convince the feamen that we had been set many miles to the northward by the current. On the 25th at noon, the longitude by our reckoning was 74° W. and I believe the computation to have been pretty juft; but the foundings, together with the latitude, will determine the ipot where thefe obfervations were made, better than any reckoning from the eastward. The hip's run on the 26th, from nine in the forenoon to four in the afternoon, was about ten leagues on a northweft-by-north courfe; foon afterwards we hove-to in order to found, and finding bottom, we went very flowly all night, and till noon the next day. From thefe obfervations, I think it may be concluded, that the Gulf-ftream, about the 33d degree of north latitude, and the 76th degree of longitude weft of Greenwich, is, in the month of April, at least fix degrees hotter than the water of the fea through which it runs. As the heat of the fea-water evidently began to increase in the evening of the 25th, and as the obfervations fhew that we were getting out of the current when I first tried the heat in the morning of the 26th, it is moft probable that the fhip's run during the night is nearly the breadth of the ftream measured obliquely a cross; that, as it blew a fresh breeze, it could not be much lefs than twenty-five leagues in fifteen hours, the diftance of time between the two obfervations of the heat; and hence the breadth of the ftream may be estimated at twenty leagues. The breadth of the Gulf of Florida, which evidently bounds the stream at its origin, appears by the charts to be two or three miles less than this, excluding the rocks and fandbanks which furround the Bahama Ilands, and the fhallow water that extends to a confiderable diftance from the coast of Florida; and the correfpondence of these meafures is very remarkable, fince the ftream, from well-known prin ciples of hydraulics, muft gradually become wider as it gets to a greater diftance from the channel by which it iffues. If the heat of the Gulf of Mexico was known, many curious calculations might be formed by comparing it with that of the current. The mean heat of Spanish town and Kingston in Jamaica, feems not to exceed 81*; that of St. Domingo on the fea-coaft may be estimated at the fame, from Monf. Godin's observations † ; but as the coaft of the continent which bounds the gulf to the westward and fouthward is probably warmer, perhaps a degree or two may be allowed for the mean temperature of the climate over the whole bay: let it be stated at 82° or 83°. Now there feems to be great probability in the fuppofition that the fea, at a certain comparatively small diftance below its furface, agrees in heat pretty nearly with the ave rage temperature of the air during the whole year in that part; and hence it may be conjectured, that the general heat of the water, as it iffues out of the bay to form the ftream, is about 82°, the small * Hiftoty of Jamaica, London, 1774, vol. iii. p. 652, 653. The different obfervations of the heat recorded in that work, do not agree together; but thofe adopted here are taken from that feries which appeared to me the most correct. + Monf. Godin's experiments upon the pendulum were made at the Petic Goave. They continued from the 24th of Auguft to the 4th of September; and the average heat during that time was fuch as is indicated by 250 of Monf. de Reaumur't thermometer (fee Mem. Acad. Scienc. 1735, P. 517.) According to Monf. de Luc's calculation (fee Modifications de l'Atmosphere, vol. i. p. 378.) the 25th degree of Monf. de Reaumur's true thermometer anfwers to about the 5th of Fahrenheit's; but the average heat in Jamaica during the months of Auguft and September, is alfo 85°; hence we may conclude, that the mean heat for the whole year is nearly the fame on the fea-coafts in both islands. The lowest calculation of the mean temperature of the gulf is preferred on this occafion, becaufe of the conftant influx of new water from the Atlantic Ocean produced by the trade-winds; which water not having been near any land, muft, I think, be fenfibly cooler than that which has remained fome time inclofed in the bay. On this fubject the obfervations made by Alexander Dalrymple, Efq. relative to the heat of the fea near the Coast of Guinea, ought to be confulted (fee Phil. Tranf. vol. lxviii. p. 394, &c.) |