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1768.

pendicular, and the neap tides four. By Dr. Heberden's ob

September. fervation, 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 sorts, 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.

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 set sail in prosecution of Monday 19. our voyage.

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

VOL. II.

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CHAP.

CH A P. 11.

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1768. September.

The Passage from Madeira to Rio de Janeiro, with some account of the Country, and the Incidents that

happened there. ON

N the 21st of September we saw 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 17° 50'. I make these islands to lie in latitude 30° 11' North, and diftant 58 leagues from Funchiale in Madeira, in the direction of S. 16 E.

Wednes. 21.

On Friday the 23d we saw 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 sunset was very striking ; when the sun was below the horizon, and the rest of the island appeared of a deep black, the mountain still 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 issues from the chinks near the top, too strong to be borne by the hand when it is held near them. We had received from Dr. Heberden, among other favours some 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

Friday 23.

also

O&ober.

also some native sulphur exceedingly pure, which he had 1768.

Septeinber. likewise found upon

the surface in great plenty. On the next day, Saturday the 24th, we came into the Saturday 24. north east trade wind, and on Friday the 30th saw Bona Vista, Friday 30. one of the Cape de Verd Islands; we ranged the cast side of it, at the distance of three or four miles from the shore, 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 illand, to the extent of a league and an half. Bona Vista by our observation lies in latitude 16 N. and longitude 21° 51 West. On the ist of October, in latitude 14° 6' N. and longitude

Saturday 1. 32° 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 seven. On the third, hoisted 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 so much advantage, because their backs are of a dark colour. We also took a shark, which proved to be the Squalus Carcharias of Linnæus.

Having lost the trade wind on the 3d, in latitude 12° 14
and longitude 22° 16', the wind became somewhat variable,
and we had light airs and calms by curns.

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 Physalis of Linnæus, and a species of the Mollusca.
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1768. October.

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Friday 7.

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It consisted of a small bladder about seven inches long, very. much resembling the air-bladder of fishes, from the bottom of which descended a number of strings, of a bright blue and red, some of them three or four feet in length, which upon being touched sting 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 so 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 exquisitely curious and beautiful.

We also took several of the thell-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 supported upon the surface of the water by a small cluster of bubbles, which are filled with air and consist of a tenacious slimy substance that will not easily part with its contents; the animal is oviparous, and these bubbles serve also as a nidus for its eggs. I is probable that it never goes down to the bottom, nor willingly approaches any shore; for the shell is exceedingly brittle, and that of few fresh water snails is so thin: every shell 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 shell 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' West, we found a current setting to the southward, which the next. day in latitude 7° 58', longitude 22° 13' thifted 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.

Saturday 8.

1763.

October.

On the roth, Mr. Banks shot the black-toed gull, not yet described according to Linnæus's system; he gave it the name

Monday 10. 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 shells, only not so full; its principal food therefore is probably the Helix just mentioned. A current to the N.W. prevailed more or less till: Monday the 24th, Monday 24. when we were in latitude 1° 7 N. and longitude 28° 50'.

On the 25th, we crossed the line with the usual ceremonies Tuesday 250 in longitude 29° 30', when, by the result of several very good azimuths, the variation was 2o 24.

On the 28th, at noon, being in the latitude of Ferdinand Friday 28. Noronha, and, by the mean of several observations by Mr. Green and myself, in longitude 32° 5' 16' W. which is to the westward of it by fome charts, and to the eastward by others, we expected to see the island, or some of the shoals 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 observed that luminous Saturday 29: appearance of the fea which has been so often mentioned by navigators, and of which such various causes have been assigned ; some fupposing it to be occasioned by fish, which agitated the water by darting at their prey, fome by the pu

, trefaction of fish and other marine animals, fome by elec-.. tricity, 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 so considerable, buc. they were so frequent that sometimes eight or ten were visible almost at the same moment. We were of opinion. that they proceeded from some luminous animal, and upon throwing out the casting net our opinion was confirmed: ic brought up a species of the Medusa, which when it came on

board

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