ROUND THE WORLD.

pendicular, and the neap tides four. By Dr. Heberden's observation, the variation of the compass here is now 15° 30′ West, and decreasing; but I have some doubt whether he is not mistaken with respect to its decrease: we found that the North point of the dipping needle belonging to the Royal Society dipped 77° 18′′.

The refreshments to be had here, are water, wine, fruit of several forts, onions in plenty, and some sweetmeats; fresh meat and poultry are not to be had without leave from the governor, and the payment of a very high price.

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1768. September.

We took in 270 lb. of fresh beef, and a live bullock, charged at 613 lb. 3,032 gallons of water, and ten tuns of wine; and in the night, between Sunday the 18th and Mon- Sunday 18. day the 19th of September, we fet fail in prosecution of Monday 19. our voyage.

When Funchiale bore North, 13 East, at the distance of 76 miles, the variation appeared by feveral azimuths to be 16° 30' Weft.

VOL. II.

C

CHAP.

1768. September. Wednef. 21.

Friday 23.

CHAP. II.

The Paffage from Madeira to Rio de Janeiro, with fome account of the Country, and the Incidents that happened there.

ON

1

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N the 21ft of September we faw the iflands called the Salvages, to the north of the Canaries; when the principal of these bore S. W. at the distance of about five leagues we found the variation of the compass by an azimuth to be 17o 50. I make these islands to lie in latitude 30° 11' North, and distant 58 leagues from Funchiale in Madeira, in the direction of S. 16 E.

On Friday the 23d we faw the Peak of Teneriffe bearing W. by S. S. and found the variation of the compass to be from 17° 22′ to 16° 30'. The height of this mountain, from which I took a new departure, has been determined by Dr. Heberden, who has been upon it, to be 15,396 feet, which is but 148 yards less than three miles, reckoning the mile at 1760 yards. Its appearance at funfet was very striking; when the fun was below the horizon, and the rest of the island appeared of a deep black, the mountain ftill reflected his rays, and glowed with a warmth of colour which no painting can express. There is no eruption of visible fire from it, but a heat iffues from the chinks near the top, too ftrong to be borne by the hand when it is held near them. We had received from Dr. Heberden, among other favours fome falt which he collected on the top of the mountain, where it is found in large quantities, and which he supposes to be the true natrum or nitrum of the ancients: he gave us

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also some native fulphur exceedingly pure, which he had likewise found upon the furface in great plenty.

1768. September.

Saturday 24

On the next day, Saturday the 24th, we came into the north east trade wind, and on Friday the 30th faw Bona Vista, Friday 30. one of the Cape de Verd Islands; we ranged the caft fide of it, at the distance of three or four miles from the fhore, till we were obliged to haul off to avoid a ledge of rocks which ftretch out S. W. by W. from the body, or S. E. point of the ifland, to the extent of a league and an half. Bona Vista by our obfervation lies in latitude 16 N. and longitude 21° 51′ Weft.

October. Saturday 1.

On the rft of October, in latitude 14° 6′ N. and longitude 22° 10' W. we found the variation by a very good azimuth to be 10° 37′ W. and the next morning it appeared to be 10°. Sunday 2. This day we found the ship five miles a-head of the log, and the next day feven. On the third, hoifted out the boat to Monday 3, discover whether there was a current, and found one to the eastward, at the rate of three quarters of a mile an hour.

During our course from Teneriffe to Bona Vista we saw great numbers of flying fish, which from the cabbin windows appear beautiful beyond imagination, their fides having the colour and brightness of burnished silver; when they are seen from the deck they do not appear to fo much advantage, because their backs are of a dark colour. We also took a fhark, which proved to be the Squalus Carcharias of Linnæus.

Having loft the trade wind on the 3d, in latitude 12° 14′ and longitude 22° 10, the wind became fomewhat variable, and we had light airs and calms by turns.

On the 7th, Mr. Banks went out in the boat and took Friday 7. what the feamen call a Portuguese man of war; it is the Holuthuria Phyfalis of Linnæus, and a fpecies of the Mollufca.

1768. October.

Friday 7.

Saturday 8.

It confifted of a small bladder about feven inches long, very. much resembling the air-bladder of fishes, from the bottom of which defcended a number of ftrings, of a bright blue and red, some of them three or four feet in length, which upon being touched fting like a nettle, but with much more force. On the top of the bladder is a membrane which is used as a fail, and turned fo as to receive the wind which way foever it blows: this membrane is marked in fine pink coloured veins, and the animal is in every respect an object exquifitely curious and beautiful.

We also took several of the fhell-fishes, or teftaceous animals, which are always found floating upon the water, particularly the Helix Janthina and Violacea; they are about the fize of a fuail, and are fupported upon the furface of the water by a small cluster of bubbles, which are filled with air and consist of a tenacious flimy substance that will not eafily part with its contents; the animal is oviparous, and these bubbles ferve alfo as a nidus for its eggs. It is probable that it never goes down to the bottom, nor willingly approaches any fhore; for the fhell is exceedingly brittle, and that of few fresh water fnails is fo thin: every fhell contains about. a tea-spoonful of liquor, which it easily discharges upon being touched, and which is of the most beautiful red. purple that can be conceived. It dies linen cloth, and it. may perhaps be worth enquiry, as the fhell is certainly found in the Mediterranean, whether it be not the Purpura of the ancients.

On the 8th, in latitude 8° 25' North, longitude 22° 4' Weft, we found a current fetting to the fouthward, which the next. day in latitude 7° 58′, longitude 22° 13′ shifted to the N. N.W. W. at the rate of one mile and a furlong an hour. The. variation here, by the mean of several azimuths, appeared to be 8° 39′ W.

1768.

October.

Monday 10.

On the roth, Mr. Banks fhot the black-toed gull, not yet described according to Linnæus's fyftem; he gave it the name of Larus crepidatus: it is remarkable that the dung of this bird is of a lively red, fomewhat like that of the liquor procured from the fhells, only not fo full; its principal food therefore is probably the Helix juft mentioned. A current to the N.W. prevailed more or lefs till Monday the 24th, Monday 24. when we were in latitude 1o 7 N. and longitude 28° 50'.

On the 25th, we crossed the line with the ufual ceremonies Tuesday 25. in longitude 29° 30′, when, by the result of several very good azimuths, the variation was 2° 24.

On the 28th, at noon, being in the latitude of Ferdinand Friday 28. Noronha, and, by the mean of several obfervations by Mr. Green and myself, in longitude 32o 5′ 16′ W. which is to the weftward of it by fome charts, and to the eastward by others, we expected to fee the island, or fome of the fhoals that are laid down in the charts between it and the main, but we faw neither one nor the other.

In the evening of the 29th, we obferved that luminous Saturday z9. appearance of the fea which has been so often mentioned by navigators, and of which fuch various caufes have been affigned; fome fuppofing it to be occafioned by fish, which agitated the water by darting at their prey, fome by the putrefaction of fish and other marine animals, fome by electricity, and others referring it into a great variety of different causes. It appeared to emit flashes of light exactly resembling those of lightning, only not fo confiderable, but. they were fo frequent that fometimes eight or ten were visible almost at the fame moment. We were of opinion. that they proceeded from fome luminous animal, and upon throwing out the cafting net our opinion was confirmed: it brought up a species of the Medufa, which when it came on

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