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Passage from the Canaries to the Isle of France. [From Nov. 13th, 1800, to March 15th, 1801.]

ON the 13th of November, in the evening, after shipping the provisions for which we had staid at the Canaries, we prepared to continue our voyage. At four o'clock we passed the little town of Candelaria, celebrated for the miracles of the virgin of that name. All this part of the island of Teneriffe appears to be as wild and barren as the coast of Anaga. In the evening we discovered the isles of Gomera and Palma, which we left to the west, and passed in the night.

On the 15th we were already under the tropic of Cancer. Op the 18th we concluded ourselves to be in the latitude of the Cape de Verd islands. From this point till we approached the Gambia, the wind was favourable, and we made considerable way, but we now experienced some obstinate calms, which prevented us from crossing the equator before the 19th of December, and in 21° 6' only of west longitude.

Notwithstanding the attempts of our commander to pass the line by 10° or 12°, all his manœuvres to effect this were constantly counteracted by the calms, the currents, or the winds. It is worthy of remark, that admiral Dentrecasteaux, nine years before, endeavouring to follow a like course to cross the equator by 16 or 18, experienced the same obstacles, and was, like us, driven by the winds and currents as far as under the 26th degree of west longitude.

On the 30th of December we passed, for the first time, the tropic of Capricorn. From the 23d to the 24th of January, 1801, we cut the meridian of Paris, in 36° south latitude.

On the 3d of February we doubled the Cape of Good Hope, at the distance of eight or ten leagues. We easily distinguished the mountain called the Table, notwithstanding the fogs with which it was at that time enveloped.

From the 3d to the 4th of March we experienced sudden and violent squalls, which, however, did not continue more than 24 hours, but they were so violent that the barometer during the time sunk 10 inches 8 lines. The Naturalist received some damage in her sails. We now found ourselves off the Mozambique channel, a latitude where violent storms are very frequent. On the 10th of March we again crossed the tropic of Capricorn. At length, on the 13th, in the evening, we were in sight of the mountains of the Isle of France, after a voyage of one hundred and forty-five days, reckoning from the time of our departure from Europe, which made this one of the longest passages we could make in a voyage of the kind. The obstinacy of our commander in ranging the coast of Africa, was the chief cause of this delay, and as it had, throughout the whole of our operations, the most fatal influence, I think I ought to dwell an instant on the subject.

Two courses naturally present themselves to the navigator who, on leaving Europe, intends to double the Cape of Good Hope: the one which may be called the coasting voyage, consists in ranging the coast of Africa, and crossing the equator as much to the east as possible. By the other course, on the contrary, after having reached the latitude of the Cape de Verd islands, steering to the west, and making for the eastern coast of America, so as not to cross the line but in 25, or even 30 degrees longitude west from the meridian of Paris.

Being arrived at about the 33d degree of south latitude, we at first found the wind N.W. then west, by favour of which we could rapidly make to the eastward, to double the famous cape of which we have spoken.

Doubtless if we had only to compare the absolute distance of these two courses, we should not hesitate to chase the coasting voyage along the shores of Africa; but the well-informed navigator takes into his calculation other circumstances than the idle consideration of relative geographical positions: he is not ignorant that the most considerable distances in appearance make little against him if he is but favoured by the wind and tides; that the shortest passage, on the contrary, may be retarded for weeks and months, if the same winds and currents oppose themselves to its progress, or what may retard him still more, obstinate calms, which keep his vessel almost immoveable on the surface of the waves.

Hence all these inconveniences are attached to the coasting of the N.W. shores of Africa. In fact, experience teaches us that the currents which prevail in this part of the Atlantic, set to the N.W. and in fine, that of all the known seas, the one which washes the equatorial part of the western coast of Africa, is most subject to calms. All well-informed navigators agree on the subject of these facts, and capt. Dampier, whose writings are the fruit of a long experience, and extremely valuable for their exactness, has particularly developed this subject in his treatise on the winds.

By the course, standing out to sea, the currents which are so fatal to the coaster, are favourable to those who bear away to the west: and the calms which am so dreadful on the African shores are seldom experienced in the open ocean, and never last long in the middle of the Atlantic. Whether the shelter of a large continent produces or occasions them in its vicinity, or that this phenomenon may be ascribed to any other physical cause, I cannot decide: in short, the westerly winds which the navigator wants on his way back, towards the 33d or the 35th degree south, are so constant in these last latitudes, that he may very fairly calculate on their assistance.

It is for good reasons that experienced navigators prefer the western course, although it appears to be the longest; that this course is certainly the best, has been sufficiently proved, ever since the first voyages of Schouten. This celebrated traveller relates, that during his first voyage from Europe to the Indies, in the year 1658, the captain of the vessel in which he had embarked, and who was an experienced seaman, had a dispute with the commander of another ship belonging to the Dutch company, which sailed as consort with him to Batavia. Schouten's captain being influenced by the reasons I have stated, chose to steer to the west; the other, on the contrary, deceived by appearances and his own inexperience, persisted that it was best to lengthen the coast of Africa. Thus, divided in opinion, each pursued a different course; but the experiment was so much in favour of Schouten's captain, that he gained near two months on the inexperienced coaster.

It is from a well-founded knowledge of all these circumstances, that the English ships which are bound to the Indies are in the habit of steering towards the coast of Brazil, so as not to cross the line but in 28°, 30°, or even in 33° west longitude; and the Company's ships have not in that respect different system from that of private vessels.

Farther, it is not only in doubling the Cape of Good Hope that they have occasion to fear the currents, and the calms on the coast of Africa; the voyages even which arc: every day made to Malembo, to Loango, or the coast of Angola, frequently encounter the most irksome delays; and here again experience teaches us, that to avoid the calms it is necessary to stretch as far as possible from the gulf of Guinea, and consequently to stand to the west, to return back, and sometimes even to the south, to make the point of destination; the same precaution should be taken by those who go from Loango for the Antilles. Captain Dampier, in fact, says, that it is necessary in such a navigation, to stand right to the westward, for the space of 30° or even 35°, before attempting to cross the line to return northward, and to take afterwards a course N.W. This route, he observes, is that of the most able navigators, and however long it may appear, it is however much shorter in reality, for those who cross the equator too far to the east to coast the shores of Africa, and stand first to the N.W. are almost always obnoxious to obstinate calms, and assailed by tempests, which are more frequent and more dangerous in the neighbourhood of the coast of Guinea than in the midst of the Atlantic ocean.

In short, M. de Granpré, whose evidence we may produce here, because he has traversed these seas for a long time, exclaims with a just severity against those ignorant or timid commanders, who, notwithstanding the fatal experience of other navigators, continue even yet to coast along the shores of Africa. He relates, among other examples or this sort, that of a vessel, which, detained by the calms, and obstructed by the currents, remained eleven months in its course from France to the coast of Angola. In a word, if it was not foreign to the nature of my work to prolong the discussion, it would be easy to produce such a number of facts and observations in favour of the course to the west, as would amount to demonstration; but it is sufficient for my present purpose, to enable the reader to judge of the extent of the fault of our commander, in persisting to steer along the coast of Africa. We shall soon find, that from this preposterous obstinacy, which was necessarily followed by a consequence plain to foresee and easy to evade, he was forced from the beginning of the voyage to disturb and discompose all the regularity of the operations which had been prescribed for him to follow: Thus, in the execution of the most important undertakings, the slightest faults produce consequences at once grievous and irreparable!

Doubtless, the relation of a passage to the Indies seems to promise but little that can now be interesting, or to furnish any new observations at a time when so many vessels of every nation have so often repeated the voyage in the course of the last three centuries. This, however, is not the fact, and to prove it, we have only to cast an eye over the many relations of the sort that have been written at different periods, We shall there see, that almost every navigator occupied exclusively on the most general or trivial objects, has only repeated what his predecessors had said a hundred times before him, neglecting every new subject of observation which this immense scene continually presents, comprising at once the whole length of the Atlantic ocean, the Indian sea, the two temperate zones, and the whole of the equinoctial line. Moreover, the subject will always furnish many interesting observations on the comparison of the temperature of the atmosphere in different latitudes of both hemispheres, on the variations of the barometer and the hygrometer in similar circumstances; the temperature of the sea on its surface, compared at different times of the day and night, with that of the atmosphere, &c.—Does not this view of the subject present a new field for the investigation of the learned traveller? while the heat of the ocean in great depths below the surface, is another fruitful source of observation and experiment that is highly interesting. Are we not still unacquainted with the depths of the seas, and the relative proportions of the saltness of their waters? Are we not still uncertain of the real cause of the phosphorescence of the ocean, a phenomenon so astonishing, so common, and nevertheless so little understood: and if we carry our investigations still farther, we shall discover an astonishing number of pelagians, animals hitherto unknown, marine plants, and zoophytes, which seem assembled as it were to present new wonders to the observer, of their organizations, and to the naturalist, of their properties.

It may be preferable to occupy one's self at this day with other objects than flying-fish, gold fish, sharks, &c. &c. and it is voyages of this description, and these alone, which are capable of furnishing the valuable materials of a physical and meteorological chart of the seas; a chart of which science stands so much in need, and where hitherto we have sought in vain for the simple elements, amidst a crowd of subjects which continually multiply themselves, and reproduce each other.

In extending my researches to each of the subjects I have mentioned, I have wished rather to point out this new pursuit, which I do not pretend to have gone through; but the results I have gained from my first attempts appear to be of such utility, that I think it my duty to give a slight sketch of them here, reserving all the details of the observations of which they are the fruit, for a future time and for a future work.