Volume I Part 7 (1/2)

The eruptions of the Peak have been very rare for two centuries past, and these long intervals appear to characterize volcanoes highly elevated. The smallest one of all, Stromboli, is almost always burning. At Vesuvius, the eruptions are rarer than formerly, though still more frequent than those of Etna and the Peak of Teneriffe. The colossal summits of the Andes, Cotopaxi and Tungurahua, scarcely have an eruption once in a century. We may say, that in active volcanoes the frequency of the eruptions is in the inverse ratio of the height and the ma.s.s. The Peak also had seemed extinguished during ninety-two years, when, in 1798, it made its last eruption by a lateral opening formed in the mountain of Chahorra. In this interval Vesuvius had sixteen eruptions.

The whole of the mountainous part of the kingdom of Quito may be considered as an immense volcano, occupying more than seven hundred square leagues of surface, and throwing out flames by different cones, known under the particular denominations of Cotopaxi, Tungurahua, and Pichincha. The group of the Canary Islands is situated on the same sort of submarine volcano. The fire makes its way sometimes by one and sometimes by another of these islands.

Teneriffe alone contains in its centre an immense pyramid terminating in a crater, and throwing out, from one century to another, lava by its flanks. In the other islands, the different eruptions have taken place in various parts; and we nowhere find those isolated mountains to which the volcanic effects are confined. The basaltic crust, formed by ancient volcanoes, seems everywhere undermined; and the currents of lava, seen at Lancerota and Palma, remind us, by every geological affinity, of the eruption which took place in 1301 at the island of Ischia, amid the tufas of Epomeo.

The exclusively lateral action of the peak of Teneriffe is a geological phenomenon, the more remarkable as it contributes to make the mountains which are backed by the princ.i.p.al volcano appear isolated. It is true, that in Etna and Vesuvius the great flowings of lava do not proceed from the crater itself, and that the abundance of melted matter is generally in the inverse ratio of the height of the opening whence the lava is ejected. But at Vesuvius and Etna a lateral eruption constantly terminates by flashes of flame and by ashes issuing from the crater, that is, from the summit of the mountain. At the Peak this phenomenon has not been witnessed for ages: and yet recently, in the eruption of 1798, the crater remained quite inactive. Its bottom did not sink in; while at Vesuvius, as M. von Buch has observed, the greater or less depth of the crater is an infallible indication of the proximity of a new eruption.

I might terminate these geological sketches by enquiring into the nature of the combustible which has fed for so many thousands of years the fire of the peak of Teneriffe;--I might examine whether it be sodium or pota.s.sium, the metallic basis of some earth, carburet of hydrogen, or pure sulphur combined with iron, that burns in the volcano;--but wis.h.i.+ng to limit myself to what may be the object of direct observation, I shall not take upon me to solve a problem for which we have not yet sufficient data. We know not whether we may conclude, from the enormous quant.i.ty of sulphur contained in the crater of the Peak, that it is this substance which keeps up the heat of the volcano; or whether the fire, fed by some combustible of an unknown nature, effects merely the sublimation of the sulphur. What we learn from observation is, that in craters which are still burning, sulphur is very rare; while all the ancient volcanoes end in becoming sulphur-pits. We might presume that, in the former, the sulphur is combined with oxygen, while, in the latter, it is merely sublimated; for nothing hitherto authorises us to admit that it is formed in the interior of volcanoes, like ammonia and the neutral salts. When we were yet unacquainted with sulphur, except as disseminated in the muriatiferous gypsum and in the Alpine limestone, we were almost forced to the belief, that in every part of the globe the volcanic fire acted on rocks of secondary formation; but recent observations have proved that sulphur exists in great abundance in those primitive rocks which so many phenomena indicate as the centre of the volcanic action. Near Alausi, at the back of the Andes of Quito, I found an immense quant.i.ty in a bed of quartz, which formed a layer of mica-slate. This fact is the more important, as it is in strict conformity with the conclusions deduced from the observation of those fragments of ancient rocks which are thrown out intact by volcanoes.

We have just considered the island of Teneriffe merely in a geological point of view; we have seen the Peak towering amid fractured strata of basalt and mandelstein; let us examine how these fused ma.s.ses have been gradually adorned with vegetable clothing, what is the distribution of plants on the steep declivity of the volcano, and what is the aspect or physiognomy of vegetation in the Canary Islands.

In the northern part of the temperate zone, the cryptogamous plants are the first that cover the stony crust of the globe. The lichens and mosses, that develop their foliage beneath the snows, are succeeded by grumina and other phanerogamous plants. This order of vegetation differs on the borders of the torrid zone, and in the countries between the tropics. We there find, it is true, whatever some travellers may have a.s.serted, not only on the mountains, but also in humid and shady places, almost on a level with the sea, Funaria, Dicranum, and Bryum; and these genera, among their numerous species, exhibit several which are common to Lapland, to the Peak of Teneriffe, and to the Blue Mountains of Jamaica. (This extraordinary fact was first observed by M. Swarz. It was confirmed by M. Willdenouw when he carefully examined our herbals, especially the collection of cryptogamous plants, which we gathered on the tops of the Andes, in a region of the world where organic life is totally different from that of the old world.) Nevertheless, in general, it is not by mosses and lichens that vegetation in the countries near the tropics begins. In the Canary Islands, as well as in Guinea, and on the rocky coasts of Peru, the first vegetation which prepares the soil are the succulent plants; the leaves of which, provided with an infinite number of orifices* (* The pores corticaux of M. Decandolle, discovered by Gleichen, and figured by Hedwig.) and cutaneous vessels, deprive the ambient air of the water it holds in solution. Fixed in the crevices of volcanic rocks, they form, as it were, that first layer of vegetable earth with which the currents of lithoid lava are clothed. Wherever these lavas are scorified, and where they have a s.h.i.+ning surface, as in the basaltic mounds to the north of Lancerota, the development of vegetation is extremely slow, and many ages may pa.s.s away before shrubs can take root. It is only when lavas are covered with tufa and ashes, that the volcanic islands, losing that appearance of nudity which marks their origin, bedeck themselves in rich and brilliant vegetation.

In its present state, the island of Teneriffe, the Chinerfe* (* Of Chinerfe the Europeans have formed, by corruption, Tchineriffe and Teneriffe.) of the Guanches, exhibits five zones of plants, which we may distinguish by the names--region of vines, region of laurels, region of pines, region of the retama, and region of gra.s.ses. These zones are ranged in stages, one above another, and occupy, on the steep declivity of the Peak, a perpendicular height of 1750 toises; while fifteen degrees farther north, on the Pyrenees, snow descends to thirteen or fourteen hundred toises of absolute elevation. If the plants of Teneriffe do not reach the summit of the volcano, it is not because the perpetual snow and the cold of the surrounding atmosphere mark limits which they cannot pa.s.s; it is the scorified lava of the Malpays, the powdered and barren pumice-stone of the Piton, which impede the migration of plants towards the brink of the crater.

The first zone, that of the vines, extends from the sea-sh.o.r.e to two or three hundred toises of height; it is that which is most inhabited, and the only part carefully cultivated. In the low regions, at the port of Orotava, and wherever the winds have free access, the centigrade thermometer stands in winter, in the months of January and February, at noon, between fifteen and seventeen degrees; and the greatest heats of summer do not exceed twenty-five or twenty-six degrees. The mean temperature of the coasts of Teneriffe appears at least to rise to twenty-one degrees (16.8 degrees Reaumur); and the climate in those parts keeps at the medium between the climate of Naples and that of the torrid zone.

The region of the vines exhibits, among its vegetable productions, eight kinds of arborescent Euphorbia; Mesembrianthema, which are multiplied from the Cape of Good Hope to the Peloponnesus; the Cacalia Kleinia, the Dracaena, and other plants, which in their naked and tortuous trunks, in their succulent leaves, and their tint of bluish green, exhibit distinctive marks of the vegetation of Africa. It is in this zone that the date-tree, the plantain, the sugar-cane, the Indian fig, the Arum Colocasia, the root of which furnishes a nutritive fecula, the olive-tree, the fruit trees of Europe, the vine, and corn are cultivated. Corn is reaped from the end of March to the beginning of May: and the culture of the bread-fruit tree of Otaheite, that of the cinnamon tree of the Moluccas, the coffee-tree of Arabia, and the cacao-tree of America, have been tried with success. On several points of the coast the country a.s.sumes the character of a tropical landscape; and we perceive that the region of the palms extends beyond the limits of the torrid zone. The chamaerops and the date-tree flourish in the fertile plains of Murviedro, on the coasts of Genoa, and in Provence, near Antibes, between the thirty-ninth and forty-fourth degrees of lat.i.tude; a few trees of the latter species, planted within the walls of the city of Rome, resist even the cold of 2.5 degrees below freezing point. But if the south of Europe as yet only partially shares the gifts lavished by nature on the zone of palms, the island of Teneriffe, situated on the parallel of Egypt, southern Persia, and Florida, is adorned with the greater part of the vegetable forms which add to the majesty of the landscape in the regions near the equator.

On reviewing the different tribes of indigenous plants, we regret not finding trees with small pinnated leaves, and arborescent gramina. No species of the numerous family of the sensitive-plants has migrated as far as the archipelago of the Canary Islands, while on both continents they have been seen in the thirty-eighth and fortieth degrees of lat.i.tude. On a more careful examination of the plants of the islands of Lancerota and Forteventura, which are nearest the coast of Morocco, we may perhaps find a few mimosas among many other plants of the African flora.

The second zone, that of the laurels, comprises the woody part of Teneriffe: this is the region of the springs, which gush forth amidst turf always verdant, and never parched with drought. Lofty forests crown the hills leading to the volcano, and in them are found four species of laurel,* (* Laurus indica, L. foetens, L.

n.o.bilis, and L. Til. With these trees are mingled the Ardisia excelsa, Rhamnus glandulosus, Erica arborea and E. texo.) an oak nearly resembling the Quercus Turneri* (* Quercus canariensis, Broussonnet.) of the mountains of Tibet, the Visnea mocanera, the Myrica Faya of the Azores, a native olive (Olea excelsa), which is the largest tree of this zone, two species of Sideroxylon, the leaves of which are extremely beautiful, the Arbutus callicarpa, and other evergreen trees of the family of myrtles. Bindweeds, and an ivy very different from that of Europe (Hedera canariensis) entwine the trunks of the laurels; at their feet vegetate a numberless quant.i.ty of ferns,* (* Woodwardia radicans, Asplenium palmatum, A. canariensis, A. latifolium, Nothalaena subcordata, Trichomanes canariensis, T. speciosum, and Davallia canariensis.) of which three species* (* Two Acrostichums and the Ophyoglossum lusitanic.u.m.) alone descend as low as the region of the vines. The soil, covered with mosses and tender gra.s.s, is enriched with the flowers of the Campanula aurea, the Chrysanthemum pinnatifidum, the Mentha canariensis, and several bushy species of Hyperic.u.m.* (*

Hyperic.u.m canariense, H. floribundum, and H. glandulosum.) Plantations of wild and grafted chestnut-trees form a broad border round the region of the springs, which is the greenest and most agreeable of the whole.

In the third zone (beginning at nine hundred toises of absolute height), the last groups of Arbutus, of Myrica Faya, and of that beautiful heath known to the natives by the name of Texo, appear.

This zone, four hundred toises in breadth, is entirely filled by a vast forest of pines, among which mingles the Juniperus cedro of Broussonnet. The leaves of these pines are very long and stiff, and they sprout sometimes by pairs, but oftener by threes in one sheath. Having had no opportunity of examining the fructification, we cannot say whether this species, which has the appearance of the Scotch fir, is really different from the eighteen species of pines with which we are already acquainted in Europe. M. Decandolle is of opinion that the pine of Teneriffe is equally distinct from the Pinus atlantica of the neighbouring mountains of Mogador, and from the pine of Aleppo,* (* Pinus halepensis. M. Decandolle observes, that this species, which is not found in Portugal, but grows on the Mediterranean sh.o.r.es of France, Spain, and Italy, in Asia Minor, and in Barbary, would be better named Pinus mediterranea. It composes the princ.i.p.al part of the pine-forests of the south-east of France, where Gouan and Gerard have confounded it with the Pinus sylvestris. It comprehends the Pinus halepensis, Mill., Lamb., and Desfont., and the Pinus maritima, Lamb.) which belongs to the basin of the Mediterranean, and does not appear to have pa.s.sed the Pillars of Hercules. We met with these last pines on the slope of the Peak, near twelve hundred toises above the level of the sea. In the Cordilleras of New Spain, under the torrid zone, the Mexican pines extend to the height of two thousand toises. Notwithstanding the similarity of structure existing between the different species of the same genus of plants, each of them requires a certain degree of temperature and rarity in the ambient air to attain its due growth. If in temperate climates, and wherever snow falls, the uniform heat of the soil be somewhat above the mean heat of the atmosphere, it is probable that at the height of Portillo the roots of the pines draw their nourishment from a soil, in which, at a certain depth, the thermometer rises at most to nine or ten degrees.

The fourth and fifth zones, the regions of the retama and the gramina, occupy heights equal to the most inaccessible summits of the Pyrenees. It is the sterile part of the island where heaps of pumice-stone, obsidian, and broken lava, form impediments to vegetation. We have already spoken of those flowery tufts of alpine broom (Spartium nubigenum), which form oases amidst a vast desert of ashes. Two herbaceous plants, the Scrophularia glabrata and the Viola cheiranthifolia, advance even to the Malpays. Above a turf scorched by the heat of an African sun, an arid soil is overspread by the Cladonia paschalis. Towards the summit of the Peak the Urceolarea and other plants of the family of the lichens, help to work the decomposition of the scorified matter. By this unceasing action of organic force the empire of Flora is extended over islands ravaged by volcanoes.

On surveying the different zones of the vegetation of Teneriffe, we perceive that the whole island may be considered as a forest of laurels, arbutus, and pines, containing in its centre a naked and rocky soil, unfit either for pasturage or cultivation. M.

Broussonnet observes, that the archipelago of the Canaries may be divided into two groups of islands; the first comprising Lancerota and Forteventura, the second Teneriffe, Canary, Gomera, Ferro, and Palma. The appearance of the vegetation essentially differs in these two groups. The eastern islands, Lancerota and Forteventura, consist of extensive plains and mountains of little elevation; they have very few springs, and bear the appearance, still more than the other islands, of having been separated from the continent. The winds blow in the same direction, and at the same periods: the Euphorbia mauritanica, the Atropa frutescens, and the arborescent Sonchus, vegetate there in the loose sands, and afford, as in Africa, food for camels. The western group of the Canaries presents a more elevated soil, is more woody, and is watered by a greater number of springs.

Though the whole archipelago contains several plants found also in Portugal,* (* M. Willdenouw and myself found, among the plants of the peak of Teneriffe, the beautiful Satyrium diphyllum (Orchis cordata, Willd.) which Mr. Link discovered in Portugal. The Canaries have, in common with the Flora of the Azores, not the d.i.c.ksonia culcita, the only arborescent heath found at the thirty-ninth degree of lat.i.tude, but the Asplenium palmatum, and the Myrica Faya. This last tree is met with in Portugal, in a wild state. Count Hoffmansegg has seen very old trunks of it; but it was doubtful whether it was indigenous, or imported into that part of our continent. In reflecting on the migrations of plants, and on the geological possibility, that lands sunk in the ocean may have heretofore united Portugal, the Azores, the Canaries, and the chain of Atlas, we conceive, that the existence of the Myrica Faya in western Europe is a phenomenon at least as striking as that of the pine of Aleppo would be at the Azores.), in Spain, at the Azores, and in the north-west of Africa, yet a great number of species, and even some genera, are peculiar to Teneriffe, to Porto Santo, and to Madeira. Such are the Mocanera, the Plocama, the Bosea, the Canarina, the Drusa, and the Pittosporum. A form which may be called northern, that of the cruciform plant (Among the small number of cruciform species contained in the Flora of Teneriffe, we shall here mention Cheiranthus longifolius, l'Herit.; Ch.

fructescens, Vent.; Ch. scoparius, Brouss.; Erysimum bicorne, Aiton; Crambe strigosa, and C. laevigata, Brouss.), is much rarer in the Canaries than in Spain and in Greece. Still farther to the south, in the equinoctial regions of both continents, where the mean temperature of the air rises above twenty-two degrees, the cruciform plants are scarcely ever to be seen.

A question highly interesting to the history of the progressive marks of organization on the globe has been very warmly discussed in our own times, that of ascertaining whether the polymorphous plants are more common in the volcanic islands. The vegetation of Teneriffe is unfavourable to the hypothesis that nature in new countries is but little subject to permanent forms. M. Broussonnet, who resided so long at the Canaries, a.s.serts that the variable plants are not more common there than in the south of Europe. May it not to be presumed, that the polymorphous species, which are so abundant in the isle of Bourbon, are a.s.signable to the nature of the soil and climate rather than to the newness of the vegetation?

Before we take leave of the old world to pa.s.s into the new, I must advert to a subject which is of general interest, because it belongs to the history of man, and to those fatal revolutions which have swept off whole tribes from the face of the earth. We inquire at the isle of Cuba, at St. Domingo, and in Jamaica, where is the abode of the primitive inhabitants of those countries? We ask at Teneriffe what is become of the Guanches, whose mummies alone, buried in caverns, have escaped destruction? In the fifteenth century almost all mercantile nations, especially the Spaniards and the Portuguese, sought for slaves at the Canary Islands, as in later times they have been sought on the coast of Guinea.* (* The Spanish historians speak of expeditions made by the Huguenots of Roch.e.l.le to carry off Guanche slaves. I have some doubt respecting these expeditions, which are said to have taken place subsequently to the year 1530.) The Christian religion, which in its origin was so highly favourable to the liberty of mankind, served afterwards as a pretext to the cupidity of Europeans. Every individual, made prisoner before he received the rite of baptism, became a slave. At that period no attempt had yet been made to prove that the blacks were an intermediate race between man and animals. The swarthy Guanche and the African negro were simultaneously sold in the market of Seville, without a question whether slavery should be the doom only of men with black skins and woolly hair.

The archipelago of the Canaries was divided into several small states hostile to each other, and in many instances the same island was subject to two independent princes. The trading nations, influenced by the hideous policy still exercised on the coast of Africa, kept up intestine warfare. One Guanche then became the property of another, who sold him to the Europeans; several, who preferred death to slavery, killed themselves and their children.

The population of the Canaries had considerably suffered by the slave trade, by the depredations of pirates, and especially by a long period of carnage, when Alonzo de Lugo completed the conquest of the Guanches. The surviving remnants of the race perished mostly in 1494, in the terrible pestilence called the modorra, which was attributed to the quant.i.ty of dead bodies left exposed in the open air by the Spaniards after the battle of La Laguna. The nation of the Guanches was extinct at the beginning of the seventeenth century; a few old men only were found at Candelaria and Guimar.

It is, however, consoling to find that the whites have not always disdained to intermarry with the natives; but the Canarians of the present day, whom the Spaniards familiarly call Islenos (Islanders), have very powerful motives for denying this mixture.

In a long series of generations time effaces the characteristic marks of a race; and as the descendants of the Andalusians settled at Teneriffe are themselves of dark complexion, we may conceive that intermarriages cannot have produced a perceptible change in the colour of the whites. It is very certain that no native of pure race exists in the whole island. It is true that a few Canarian families boast of their relations.h.i.+p to the last shepherd-king of Guimar, but these pretensions do not rest on very solid foundations, and are only renewed from time to time when some Canarian of more dusky hue than his countrymen is prompted to solicit a commission in the service of the king of Spain.

A short time after the discovery of America, when Spain was at the highest pinnacle of her glory, the gentle character of the Guanches was the fas.h.i.+onable topic, as we in our times laud the Arcadian innocence of the inhabitants of Otaheite. In both these pictures the colouring is more vivid than true. When nations, wearied with mental enjoyments, behold nothing in the refinement of manners but the germ of depravity, they are pleased with the idea, that in some distant region, in the first dawn of civilization, infant society enjoys pure and perpetual felicity. To this sentiment Tacitus owed a part of his success, when he sketched for the Romans, subjects of the Caesars, a picture of the manners of the inhabitants of Germany. The same sentiment gives an ineffable charm to the narrative of those travellers who, at the close of the last century, visited the South Sea Islands.

The inhabitants of those islands, too much vaunted (and previously anthropophagi), resemble, under more than one point of view, the Guanches of Teneriffe. Both nations were under the yoke of feudal government. Among the Guanches, this inst.i.tution, which facilitates and renders a state of warfare perpetual, was sanctioned by religion. The priests declared to the people: ”The great Spirit, Achaman, created first the n.o.bles, the achimenceys, to whom he distributed all the goats that exist on the face of the earth.

After the n.o.bles, Achaman created the plebeians, achicaxnas. This younger race had the boldness to pet.i.tion also for goats; but the supreme Spirit answered, that this race was destined to serve the n.o.bles, and that they had need of no property.” This tradition was made, no doubt, to please the rich va.s.sals of the shepherd-kings.