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Our Stay in the Isle of France. [From the 15th of March to the 25th of April, 1801.]

AFTER so long a voyage, the sight of any portion of land Is doubtless delightful to the traveller; but how much more does it appear interesting, when he knows that he shall find on it the men, manners and language of his native country. Besides, the picturesque appearance of the Isle of France, the singular shapes of its mountains, the verdure which clothes the whole surface of the island, the numerous habitations which he discovers at a distance, all contribute something to the charm of having reached the first goal or resting place of his voyage.

The Isle of France was first discovered by the Portuguese, who named it Cerné; it was afterwards in the possession of the Dutch, who called it Isle-Maurice; it now belongs to the French, who again changed its name to that it is now known by, the Isle of France. It is a small island in the Indian sea, and is generally called a part of Africa; it is situated near the tropics, being only three degrees from that of Capricorn; it is of an irregular oval form; its greatest length is not above eleven leagues; it is in breadth hardly eight; the circumference is reckoned about forty-five, and the surface, according to the abbé de Lacaille, is 432,680 toises; it is thirty leagues N.E. of the Isle Reunion, the soil of which, like that of the Isle of France, is entirely volcanic, but the mountains are more lofty; one of them is also a burning volcano. The prevailing winds at the Isle of France are, the E.S.E. the S.E. and the S.S.E.; that is to say, the most pleasant and healthy that we can possibly have in these latitudes. Those which blow from the N. and the W. and particularly the N.W. are generally rainy and almost always attend the hurricanes which from time to time lay waste the colony. But it is said that these hurricanes happen but seldom since the lands have been so much cleared. The hurricanes of these latter days, which have been most spoken of, are those which happened in the years 1786, and 1789. The first took place on the 15th of December, when the sea rose three feet eight inches above the level of the highest tides; the barometer sunk W, 3 lines; and there fell in the course of twenty-four hours, 73 lines of rain water; and independent of the thunder and lightning, which was almost incessant the whole tithe of this dreadful hurricane, there appeared a meteor like a globe of fire, which followed the direction of the wind, which was then N.W. and went behind the mountains of Mocha. This meteor was very high in the atmosphere, and appeared, half as large as the moon.

The second hurricane, still more disastrous than the former, happened at the same time in the month, namely, on the 15th of December, 1789; it lasted about twenty three hours, during which time the barometer sunk 14, 9 lines; and the mercury in the tube was so strongly agitated, that oscillations were considerable, and there rose from its surfaces sparks of pale light, which filled all that was empty of the tube. The sea raged horribly, and the waves were so impetuous, that several ships were driven on the rocks and wrecked; some were even overset that were at anchor in the middle of the port. The quarters of Mocha, of Flacq, of Pamplemousses, and the Riviere du Rempart, were more particularly devastated by this last hurricane, during which there fell 104 lines of rain water.

Notwithstanding the momentaneous disasters which are the consequences of these hurricanes, experience seems to prove that they are a real benefit to the Country; and that this sort of periodical revolution gives new strength to the soil, and makes the atmosphere more salubrious. Thus Nature, benevolent in all her works, makes evil itself one of the most powerful agents in producing good.

Earthquakes happen but seldom in the Isle of France; but in the morning, on the fourth of August, 1786, two strong shocks were felt, which, however, did not do any damage.

As in our own climates, it thunders in the hottest months, that is to say, it generally happens in October; November, December, and January. The mean term of nine years' observation on this subject, gives about fifteen days of thunder in each month.

Hail is a phenomenon which rarely happens, but, nevertheless, there are same instances; for example, it hailed in the plains of Mocha on the 10th of December, 1799.

Rain falls very frequently, and in great abundance. At the N.W. port, the days of rain amounted in a year, from 105 to 140, and in the plains of Mocha they were still more numerous. In the year 7 of the revolution, they were reckoned at 198; in the year 8, 193; which, on an average, makes above half the days of the year rainy.

This frequent rain, the height of the mountains, the forests which cover the summits, and the basaltic nature of the soil, which prevents the earth imbibing much of the water to any great depth, seem to be considered as the chief causes of the multiplicity of the rivers, of which there are above forty, independent of smaller streams, springs, and numerous torrents in every part of the island; the rivers, indeed, are not very considerable, but they nevertheless contain an immense quantity of water, if we suppose them collected together in one mass. This great number of rivers and streams power, fully assists the natural fertility of the soil, and that strength of vegetation, of which we cannot have a perfect idea in mates not so much favoured by nature.

However abundant the rains may still be in, the Isle of France, it is the general opinion of the country, that they have much diminished in the course of the last twenty-five or thirty years, and the clearing of the lauds, which latterly is particular, has been done without proper consideration, is universally thought to be the principal cause of this diminution. And the oldest and best-informed agriculturists assert; that the rivers convey much less water than formerly; that several springs have dried up, and that vegetation is not so quick; and this last effect is ascribed not so much to the soil being exhausted, as to the deficiency of its natural humidity. It is certainly not impossible, that the inconsiderate act of clearing the forests may have been one great cause of the diminution of the quantity of rain; but it is also possible, that if the quantity be still the same as formerly, it may not now be sufficient for the vegetation, because the first effect of the denudation of the soil, is to occasion a quicker and greater evaporation. But whatever weight this last observation may have, it is nevertheless incontestable, that the clearing of the lands, has been followed in most parts of the island by the effects above mentioned. In the environs of the port N.W. there are now scarce any woods, and M. Ceré told me, that he had seen in his youth the whole of the great plain, of Pamplemousses covered with forests; it is now crowded with habitations.

The temperature of the Isle of France is not so hot as its latitude seems to denote, for after a course of daily observations during three years, made with particular attention to the subject, on the estate of Minissy, belonging to one of the brothers of the family of Monneron, a name as much respected in India as in Europe, I found that the maximum of heat was scarcely 22° in the year 7; 21° 81 in the year 8; and 22° in the year 9; the minimum was from 13° to 14° for each of these same years. It is generally in the summer as high as from 18 to 20°, and during the winter from 15 to 18°. Thus, in all this part of the island they are generally in the habit of lighting fires in winter; the evenings particularly are very cool, and I have myself felt cold for want, of more covering in the night.

In the plains of Pamplemousses, the temperature is not hotter than in the plains of Wilhems and Mocha. M. Ceré, who for thirty years carefully observed the variations of the thermometer, told me that this instrument very seldom rose so high as 25°; that this scarcely happened once in a year for five years together; that it was still seldom that it rose to 26°, and that in this case it happened during the time of very extraordinary heats, violent storms, or even hurricanes. When exposed to the heat of the sun, several times at twelve o'clock at noon, his thermometer did not rise higher than 40°. This remarkable circumstance of the little elevation of the temperature of the Isle of. France, in the interior of the country, depends, First, on the small size of the island; Secondly, on its isolated situation in the middle of the seas; Thirdly, on the nature of the prevailing winds; Fourthly, from the high mountains which cover part of its surface; Fifthly, from the forests, which in the interior are yet very extensive; Sixthly, from the frequent and abundant rains; and Seventhly, from the multiplicity of the rivers and springs, which usually occasion a cool air in the valleys.

To the N.W. of the port the temperature is much warmer than in the rest of the island; in fine, from a long course of observations on this subject by M. Lislet correspondent of the Academy of Sciences, it appears that the maximum of heat experienced in the city of the port, is annually 28° 29, and even 29° 5. The thermometer however never rises so high as 30°; at least M. Lislet himself never observed it at that height. The months of December, January, and February, are the hottest. It is not only from the temperature being warmer, that the atmosphere of the port N.W. occasions lassitude and fatigue; it is caused more by the stagnation it sometimes suffers, and which increases sensibly as The heat of the imprisoned air becomes greater, land locked as it is on all sides by the mountains of La Decoveste, Du Pouce, Du Pittes-both, and the long mountain, a disposition which prevents the immediate action of the fresh and salutary gales from the and S.S.E. of which I have spoken.

Except in the time of a hurricane, the barometer, in the N.W. part of the port remains generally from 27 inches 9 lines, to 28 inches 3 and even 4 lines; but in the more de, voted plains of Mocha, the barometer rarely ascends above 27 inches, and it is almost always below this point.

These considerations on the physical situation of the Isle of France, are not only necessary to be known as Connected with the meteorology, they also apply particularly to the health of the inhabitants. It is easy to conceive, that from ail these observations, the elasticity, freshness, and lightness of the air in the vicinity of Mocha, the plains of Wilhems, &c. is much more salutary to persons in an impaired state of health, or to convalescents, than the close air of the port N.W.; and that for the same reason, the elastic air of the plains of Wilhems is not so proper for those individuals who suffer under any stomach complaint. Experience confirms the justice of these observations. Notwithstanding this objection, it would be very unjust to think it a cause of complaint, because it is to these qualities of the air that the particular salubrity of the Isle of France is to be ascribed, as well as the climate being free from the dreadful fevers which are so common in Batavia, the Philippines, the Moluccas, Madagascar, and most of the countries near the equator.

We must not, however, believe with some enthusiasts, that all endemic distempers are unknown in the Isle of France; for unfortunately there are several, so, much the more to be feared, as they seem difficult to be avoided. In fact, independent of stomach complaints, which are here very frequent, and of the leprosy, which, although formerly unknown in this island, now prevails among many even of the white population, all the distempers of the urinary passages affect the inhabitants to an extraordinary degree: they seem to proceed from the quality of the water, which, according to the chemical analysis of M. Delisse, contains a great proportion of carbonate of lime.

I have thus, from my own particular observations, and according to the general results which I could deduce from those of Messrs. Ceré, Monneron, and particularly those of M. Lislet Geoffroy, hastily given a meteorological sketch of the Isle of France. The geological and meteorological de, tails which follow, appear to me to be equally new as inter resting; they are the observations of our mineralogist, M. Bailly.

"The Isle of France is entirely volcanic; but many centuries have elapsed since the fires have become extinct; and a great revolution seems to have changed the original state of this ancient crater. Indeed all the mountains of this, island surround if like a girdle of immense ramparts; they have all a declivity more or less towards the sea-shore, whilst towards the centre of the island, they each present an irregular mouth or cup, which cavities are often on the peak or top.

"All these mountains are formed of parallel strata inclined towards the sea from the centre of the island. These strata correspond exactly one with another, and wherever you see them interrupted by valleys or deep fissures, they are again observable on the other side of the mountains which they form. From these observations it is incontestably proved, that they have all the same origin, and that they may be dated from the same epoch; that, united in fewer ages, they could only have been since separated by some sudden and violent revolution of nature.

"Let us consider a moment what this last revolution could have been. Every fact proves, that in former times the whole island was but one enormous burning mountain; and that exhausted by the eruptions, and sunk down by its own weight, it swallowed in its abyss the greatest part of its own mass, and that of this immense vault there now remains only the foundations of which the half-open, broken parts in different places, form the present mountains of the islands. Some points or peaks of a conic shape, which rise towards the centre of the country, bear the character of an origin posterior to the sinking of the crater, and seem to have been the last spiracles or vents through which the subterranean fires exhaled their vapours.

"Such, in general, is the physical organization of the Isle of France. I shall not unnecessarily enlarge on the subject, but I must take notice of the rocks which compose the soil: they generally belong to the class described by M. Dolomieu under the name of argilo-ferruginous lava: these are more or less porous, almost always porphyritic, with crystals of a green colour in divers shades.

"These rocks are easily broken, and the earthy particles driven by the rains, form in the low places of the island, beds of some thickness, of a sort of clayey, reddish earth, which is used in the potteries, for water coolers, &c. &c.

"There is to be found in the pores and cavities of some of the strata, carbonated and crystallized lime of various shapes and different sorts. In some low marshy places a species of iron is found, in grains as large as nuts; in these places mines were formerly attempted to be worked, but a scarcity of wood, and the great price of manual labour, soon caused the attempt to be abandoned.

"To conclude this geological account of the Isle of France, I ought to add, that it is surrounded on every side by a girdle of madrepores, which makes the landing very dangerous. These madrepores become every day more extended; several small islands are formed therewith, and others are continually forming of the same elements; while the principal island is also thus enlarging more and more. We have ourselves seen a remarkable instance of the rapid increase of the zoophytes. The port admiral's ship was stranded some time after our departure; and at our return, that is to say, two years and a half after, the madrepores had increased in such a manner all over the hull of the ship, that it had become but one substance with the rock on which it rested."

The soil of the Isle of France is, as we have noticed, essentially volcanic; but at the same time very different from that of Teneriffe: it is almost every where covered with a bed of earth, which at once absorbs the waters and assists the vegetation. If I can judge from my own observations on this subject, it appears to me evident, that the principal source of this valuable earth is derived from the lava itself, decomposed by the united powers of time, heat, moisture, vegetation, &c. I have seen in the compact masses of lava, which form the mountains of the island, a progressive change, which, from the hardest basalt by a number of intermediate modifications, became vegetative earth. The action of a strong fire on this earth changes it to the colour of deep red ochre, which is doubtless caused by a stronger oxydation of the iron it contains, which is almost in a metallic state in the basalt.

But whatever may be the origin of this vegetative earth, it is nevertheless of a very excellent quality, and where it is of any considerable depth, vegetation is produced with an extraordinary degree of vigour; and the number and quantity of plants cultivated with success in the Isle of France is truly prodigious; and what is still more remarkable in the midst of this abundance, is, that almost the whole of the vegetables are foreign to the soil, and yet all succeed equally well. To have a just idea of this fertility of the country which is the subject of these observations, we ought to visit the gardens of the government in the plains of Pamplemousses; where the respectable M. Ceré has skilfully naturalized, in the space of thirty years, a prodigious number of trees and shrubs, some from the ardent climates of Africa, others from the humid shores of Madagascar; some from China and Pegu, and again, others are natives of the banks of Indus and the Ganges; several are the produce of the summits of the Ghauts, others flourished originally in the rich valleys of Cashmere; and in the isles of the great archipelago of Asia, Java, Sumatra, Ceylon, Bouro, the Moluccas, and the Philippines: Taïti itself has contributed to the richness and beauty of this garden. The Canaries, the Azores, the orchards and groves of Europe, and the forests of America, are there combined, and we may there also find several plants of Arabia, Persia, Brazil, of the coast of Guinea, Cafraria, &c. and we ourselves added to the collection numerous specimens of the curious vegetables of the south. In this garden we may ramble: through, long and silent walks, contemplating these inestimable natives of different shores assembled together, a subject of pleasing astonishment. Here we see the giant of the equinoctial forests, they teak, with which ships are built in India, almost unperishable; the bread-fruit tree, with the produce of which all the population of the countries in the southern ocean are; supplied with food; the rafia of Madagascar, a valuable species of palm, which furnishes a delicate kind of sago; the nutmeg-tree, which, lately imported by the respectable M. Poivre, may soon be expected to free us from the duty we yet pay to the Dutch monopoly; the clove-tree, whose innumerable and beautiful red fruit so much delight the eye, and which also already supply our isles with a mach greater quantity of cloves than is necessary for our own consumption; the badam-tree, with large leaves of beautiful verdure, and which bears a small almond of a long shape, and of a finer flavour than any of our nuts; the ebony-tree, which produces the wood so valuable for its beautiful polish, and shining black colour; the Pamplemousse tree, with fruit which is a species of orange, of the size of a small melon, of the rind of which is made excellent sweetmeats; the tamarind tree, bearing a fruit well known as being both pleasant to the taste, and medicinal; the dwarf orange tree of China, only one foot in height, and the fruit of which is scarcely so large as is of the coffee-tree, but which, like that of the coffee, is red. This tree is remarkable for its agreeable scent, similar to that of the lemon; The hymenœa, a beautiful tree, bearing leaves by two and two, opposite to each other—the symbol of a happy union; the areka tree, which produces the areka nut, so much in estimation on account of the betel, of which these nuts are the principal ingredient; the carambole, the fruit divided into four projecting quarters, containing a quantity of lightly acidulated juice; the jacquier, not unlike the bread-tree, and which bears a very large fruit of the shape of a long gourd, or pumpkin, and is the valuable food of the slaves; the litchi, whose tough swelling coat contains a pleasant scented pulp; the mangoustan, originally from China, in these regions thought to be the finest fruit in the world; the coffee-tree, so well known in Europe, whose little berries, containing two seeds each, are covered with a husk of fine scarlet; the mango, similar to our pear and which improved by culture, produces numerous varieties; the banana tree; whose name alone makes the mouth water of any one acquainted with its excellence; the cocoa tree, so celebrated in the writings of all travellers, and which produces such effect in equatorial landscape; the palmist, or cabbage tree, which only bears once in its life, the choice fruit which ends the existence of the tree, and which is used in so many different ways; the velongos of Madagascar, whose fruit is disposed in large regular branches, representing an enormous bunch of lobsters; the jambos, whose ripe fruit is not unlike the damson, but much sweeter in smell and taste; the jam-malac, of which is formed the most beautiful hedges; the thorny bamboo, for impenetrable enclosures; the raven-tsara, the leaves and fruit of which would furnish a very cheap and agreeable spice; the avocacier, the fruit of which somewhat resembles our mellow pears, but being more insipid, requires some addition to make it pleasant to the taste; the guava tree, which in the midst of woods furnishes a wholesome refreshment; the cinnamon tree of Cochin China, the bark of which is not inferior to that of Ceylon; the baobab, or monkey bread, the famous Adansonia, the grandest and largest kind of tree known; the vacois, whose branches wantonly descend, and again take root: the leaves of this tree are collected for many, useful purposes; the frangipane tree, whose beautiful corollas, white as alabaster, exhale a sweet and delicate perfume; the cotton tree, which yields a soft and admirable down, after the maturity of the seeds which it covers; the valuable tree of the iron-wood, which is of such rapid growth, and which thrives in the most barren soil as well as in our southern climates; the attier, whose fruit contains under a thick hard rind, a delicious pulp, compared by many travellers to sugared cream; the rose tree of China, which growing wild in fife middle of the woods and forests, unites its flowers with those of the jasmine and the beautiful pervench of Madagascar; the papaw tree, the milky and caustic juice of which is used as an excellent vermifuge, and whose fruit is seen at the best tables; the ravinal, or the traveller's tree, so named from the singular property which it has of producing a large quantify of very good soft water, when the base of the leaves is pierced: the jam-rosa, which bears fruit of a fine rose colour, from which is obtained by fermentation and distillation, a finely scented alcohol; the cassia tree, which furnishes medicine with one of its most gentle and innocent purgatives; the date tree, the caroub tree, the myrobotan, the behen tree, the varnish tree, the frankincense tree, the tallow tree, the tea tree, the coffee of Eden, the wax tree of Cochin China, the soap tree, the cubeb tree, the cacao tree, the tree of Cythera, the milk tree, the roucon tree, the velvet tree, &c. &c. But such is the profusion of useful vegetables which industry and activity have brought together in so small a theatre, that it would much exceed the limits of this chapter to continue the enumeration; and when we consider that this prodigious multiplication of interesting vegetables, is the result of a few years' experience and labour, we cannot avoid being penetrated with gratitude towards the authors of such benefits to society, at the head of whom appear Labourdonnais, the immortal Poivre, Hubert and Ceré, Commerson, Du Petit-Thonars, and Martin. The importation of the cherry immortalized the name of cullus among the Romans, and it is esteemed among as to the present day. Bow many modern naturalists have done a hundred times more than Lucullus for the human species, and nevertheless have lived unfortunate, and have died unknown, even among their own countrymen!

To conclude this general account which I have sketched, it remains for me to mention the animals and inhabitants of the Isle of France, for other climates and other people must be the subjects of our farther observations: let us therefore finish what remains to be said of our stay in this island. However the individuals belonging to our expedition were pleased with the reception they experienced from the inhabitants of the colony, our commander had reason to repent having touched at this places but without entering into the sad details of this part of our story, it shall suffice to say, that the third ship which was to have. joined us there, was refused us, and that we could not procure any of the most necessary provisions; that we lost forty excellent seamen, who here deserted, and that a great number of officers, naturalists, and artists belonging to our two ships, already tired and disgusted with the ill usage they had experienced from our commander, or justly alarmed for the future, chose to remain on the island.

It is generally allowed, that the wood of hot climates is heavier and stronger than those, of more temperate regions. The experiments of M. Lislet support this opinion; and in fact, it proved that the European oak, thus compared with 22 kinds of equatorial wood, is but 17l for the weight, and 19l for the relative strength. See the following table;

Table of the Weight and Relative Strength of several Kinds of Timber of the Isle of France, compared by M. Lislet Geoffroy, Captain of Engineers, and Correspondent to the Academy of Sciences.

General Name.	Botanic Name.	Weight of the Cubic Foot.	Relative Strength.
——————	——————	——	——	———
		lb.	oz.
Black Iron Wood	Stadtmania	87	12	3872
Stinking Wood	Fœtidia	75	2	3141
{Wood of the Natte, small- {leaved	Imbricaria	74	1	3100
Wood of the White Olive	Olea	63	2	2917
[—— of the Red Teck- [tackamaka	Tectona Grandis	53	2	2720
{—— of the Natte, large- {leaved	Imbricaria	72	1	2660
Red Iron Wood	——	84	10	2367
[Wood of the White Cinna- [mon	Laurus	56	8	2317
{Wood of the Black Cinna- {mon	Elœcarpus	41	14	2290
——of the Red Olive	Rubentia	56	6	2037
——of Red Colophane	Colophonia Burseria	59	2	2087
——of the White Apple	Eugenia	61	4	2015
——Natte, Monkey Apple	Syderoxylon	57	3	1900
——Lousteau	Antirrhœa	56	8	1750
——Benjoin	Terminalia Benjoin	57	4	2005
——Marbled Cinnamon	Eleocarpus	38	14	1880
White Iron Wood	Syderoxylon	58	4	1788
Wood of the Red Apple	Eugenia	60	0	1750
—— of the Oak	Quercus robur	56	1	1702
—— of Tackamaka Red Fir	Calophyllum Caloba	52	5	1618
—— of Bigainou	Eugenia	64	3	1500
—— of Bassin	Blackwellia	47	11	1500
—— of White Colophane	Morignia	49	3	1350

Experiments to decide the relative strength of the woods may be made several ways: that used by M. Lislet was, choosing the pieces, as much as possible, of an equal size in every respect, of each of the sorts of wood which he wished to compare, and then to fix them by the two extremities on two substantial points of support—for example, two notched posts—and then to suspend from the middle of each of the pieces of wood, a weight of sufficient force to break them. The agreement between this quantity of weight determines that of the strength of the wood, For example, if to break a piece of timber of the black fir, it requires a weight equal to 3872, and to produce the same effect on a similar piece of oak, it only requires a weight equal to 1702, it appears that the strength of resistance of these two timbers ought to agree, as 3872 with 1702; or more simply, that the strength of the oak is to that of the black fir as 1 is to 2.22.