Volume I Part 4 (1/2)
0 : 2040 : 3976 : 2460 : 4794 : 420 : 818 : 27 : 21.6.
20 : 1550 : 3020 : 2360 : 4598 : 810 : 1578 : 24.5 : 19.6.
40 : 0 : 0 : 1540 : 3001 : 1540 : 3001 : 17 : 13.6.
This table presents only the ordinary state of nature, that is to say, the phenomena as they are annually observed. Exceptions founded on particular local circ.u.mstances, exist. Thus it sometimes snows, though seldom, at Naples, at Lisbon, and even at Malaga, consequently as low as the 37th degree of lat.i.tude: and, as we have just observed, snow has been seen to fall at Mexico, the elevation of which is 1173 toises above the level of the ocean. This phenomenon, which had not been seen for several centuries, took place on the day that the Jesuits were expelled, and was attributed by the people to that act of severity. A more striking exception was found in the climate of Valladolid, the capital of the province of Mechoacan. According to my measures, the height of this town, situate in lat.i.tude 19 degrees 42 minutes, is only a thousand toises: and yet, a few years before our arrival in New Spain, the streets were covered with snow for some hours.
Snow had been seen to fall also at Teneriffe, in a place lying above Esperanza de la Laguna, very near the town of that name, in the gardens of which the artocarpus flourishes. This extraordinary fact was confirmed to M. Broussonnet by very aged persons. The Erica arborea, the Myrica Faya, and the Arbutus callicarpa,* (*
This fine arbutus, imported by M. Broussonnet, is very different from the Arbutus laurifolia, with which it has been confounded, but which belongs to North America.) did not suffer from the snow; but it destroyed all the vines in the open air. This observation is interesting to vegetable physiology. In hot countries, the plants are so vigorous, that cold is less injurious to them, provided it be of short duration. I have seen the banana cultivated in the island of Cuba, in places where the thermometer descends to seven centesimal degrees, and sometimes very near freezing point. In Italy and Spain the orange and date-trees do not perish, though the cold during the night may be two degrees below freezing point. In general it is remarked by cultivators, that the trees which grow in a fertile soil are less delicate, and consequently less affected by great changes in the temperature, than those which grow in land that affords but little nutriment.* (* The mulberries, cultivated in the thin and sandy soils of countries bordering on the Baltic Sea, are examples of this feebleness of organization. The late frosts do more injury to them, than to the mulberries of Piedmont.
In Italy a cold of 5 degrees below freezing point does not destroy robust orange trees. According to M. Galesio, these trees, less tender than the lemon and bergamot orange trees, freeze only at ten centesimal degrees below freezing point.)
In order to pa.s.s from the town of Laguna to the port of Orotava and the western coast of Teneriffe, we cross at first a hilly region covered with black and argillaceous earth, in which are found some small crystals of pyroxene. The waters most probably detach these crystals from the neighbouring rocks, as at Frascati, near Rome.
Unfortunately, strata of ferruginous earth conceal the soil from the researches of the geologist. It is only in some ravines, that we find columnar basalts, somewhat curved, and above them very recent breccia, resembling volcanic tufa. The breccia contain fragments of the same basalts which they cover; and it is a.s.serted that marine petrifactions are observed in them. The same phenomenon occurs in the Vicentin, near Montechio Maggiore.
The valley of Tacoronte is the entrance into that charming country, of which travellers of every nation have spoken with rapturous enthusiasm. Under the torrid zone I found sites where nature is more majestic, and richer in the display of organic forms; but after having traversed the banks of the Orinoco, the Cordilleras of Peru, and the most beautiful valleys of Mexico, I own that I have never beheld a prospect more varied, more attractive, more harmonious in the distribution of the ma.s.ses of verdure and of rocks, than the western coast of Teneriffe.
The sea-coast is lined with date and cocoa trees. Groups of the musa, as the country rises, form a pleasing contrast with the dragon-tree, the trunks of which have been justly compared to the tortuous form of the serpent. The declivities are covered with vines, which throw their branches over towering poles. Orange trees loaded with flowers, myrtles, and cypress trees encircle the chapels reared to devotion on the isolated hills. The divisions of landed property are marked by hedges formed of the agave and the cactus. An innumerable quant.i.ty of cryptogamous plants, among which ferns are the most predominant, cover the walls, and are moistened by small springs of limpid water. In winter, when the volcano is buried under ice and snow, this district enjoys perpetual spring.
In summer, as the day declines, the breezes from the sea diffuse a delicious freshness. The population of this coast is very considerable; and it appears to be still greater than it is, because the houses and gardens are distant from each other, which adds to the picturesque beauty of the scene. Unhappily the real welfare of the inhabitants does not correspond with the exertions of their industry, or with the advantages which nature has lavished on this spot. The farmers are not land-owners; the fruits of their labour belong to the n.o.bles; and those feudal inst.i.tutions, which, for so long a time, spread misery throughout Europe, still press heavily on the people of the Canary Islands.
From Tegueste and Tacoronte to the village of St. Juan de la Rambla (which is celebrated for its excellent malmsey wine), the rising hills are cultivated like a garden. I might compare them to the environs of Capua and Valentia, if the western part of Teneriffe was not infinitely more beautiful on account of the proximity of the peak, which presents on every side a new point of view. The aspect of this mountain is interesting not merely from its gigantic ma.s.s; it excites the mind, by carrying it back to the mysterious source of its volcanic agency. For thousands of years, no flames or light have been perceived on the summit of the Piton, nevertheless enormous lateral eruptions, the last of which took place in 1798, are proofs of the activity of a fire still far from being extinguished. There is also something that leaves a melancholy impression on beholding a crater in the centre of a fertile and well cultivated country. The history of the globe informs us, that volcanoes destroy what they have been a long series of ages in creating. Islands, which the action of submarine fires has raised above the waters, are by degrees clothed in rich and smiling verdure; but these new lands are often laid waste by the renewed action of the same power which caused them to emerge from the bottom of the ocean. Islets, which are now but heaps of scoriae and volcanic ashes, were once perhaps as fertile as the hills of Tacoronte and Sauzal. Happy the country, where man has no distrust of the soil on which he lives!
Pursuing our course to the port of Orotava, we pa.s.sed the smiling hamlets of Matanza and Victoria. These names are mingled together in all the Spanish colonies, and they form an unpleasing contrast with the peaceful and tranquil feelings which those countries inspire. Matanza signifies slaughter, or carnage; and the word alone recalls the price at which victory has been purchased. In the New World it generally indicates the defeat of the natives: at Teneriffe, the village of Matanza was built in a place* (* The ancient Acantejo.) where the Spaniards were conquered by those same Guanches who soon after were sold as slaves in the markets of Europe.
Before we reached Orotava, we visited a botanic garden at a little distance from the port. We there found M. Le Gros, the French vice-consul, who had often scaled the summit of the Peak, and who served us as an excellent guide. He was accompanying captain Baudin in a voyage to the West Indies, when a dreadful tempest, of which M. Le Dru has given an account in the narrative of his voyage to Porto Rico, forced the vessel to put into Teneriffe. There M. Le Gros was led by the beauty of the spot to settle. It was he who augmented scientific knowledge by the first accurate ideas of the great lateral eruption of the Peak, which has been very improperly called the explosion of the volcano of Chahorra. This eruption took place on the 8th of June, 1798.
The establishment of a botanical garden at Teneriffe is a very happy idea, on account of the influence it is likely to have on the progress of botany, and on the introduction of useful plants into Europe. For the first conception of it we are indebted to the Marquis de Nava. He undertook, at an enormous expense, to level the hill of Durasno, which rises as an amphitheatre, and which was begun to be planted in 1795. The marquis thought that the Canary Islands, from the mildness of their climate and geographical position, were the most suitable place for naturalising the productions of the East and West Indies, and for inuring the plants gradually to the colder temperature of the south of Europe. The plants of Asia, Africa, and South America, may easily be brought to Orotava; and in order to introduce the bark-tree* into Sicily, Portugal, or Grenada, it should be first planted at Durasno, or at Laguna, and the shoots of this tree may afterwards be transported into Europe from the Canaries. (* I speak of the species of bark-tree (cinchona), which at Peru, and in the kingdom of New Granada, flourish on the back of the Cordilleras, at the height of between 1000 and 1500 toises, in places where the thermometer is between nine and ten degrees during the day, and from three to four during the night. The orange bark-tree (Cinchona lancifolia) is much less delicate than the red bark-tree (C. oblongifolia).) In happier times, when maritime wars shall no longer interrupt communication, the garden of Teneriffe may become extremely useful with respect to the great number of plants which are sent from the Indies to Europe; for ere they reach our coasts, they often perish, owing to the length of the pa.s.sage, during which they inhale an air impregnated with salt water. These plants would meet at Orotava with the care and climate necessary for their preservation. At Durasno, the protea, the psidium, the jambos, the chirimoya of Peru,* (* Annona cherimolia. Lamarck.) the sensitive plant, and the heliconia, grow in the open air. We gathered the ripened seeds of several beautiful species of glycine from New Holland, which the governor of c.u.mana, Mr. Emparan, had successfully cultivated, and which grow wild on the coasts of South America.
We arrived very late at the port of Orotava,* (* Puerto de la Cruz.
The only fine port of the Canary Islands is that of St. Sebastian, in the isle of Gomara.) if we may give the name of port to a road in which vessels are obliged to put to sea whenever the winds blow violently from the north-west. It is impossible to speak of Orotava without recalling to the remembrance of the friends of science the name of Don Bernardo Cologan, whose house at all times was open to travellers of every nation.
We could have wished to have sojourned for some time in Don Bernardo's house, and to have visited with him the charming scenery of St. Juan de la Rambla and of Rialexo de Abaxo.* (* This last-named village stands at the foot of the lofty mountain of Tygayga.) But on a voyage such as we had undertaken, the present is but little enjoyed. Continually haunted by the fear of not executing the designs of the morrow, we live in perpetual uneasiness. Persons who are pa.s.sionately fond of nature and the arts feel the same sensations, when they travel through Switzerland and Italy. Enabled to see but a small portion of the objects which allure them, they are disturbed in their enjoyments by the restraints they impose on themselves at every step.
On the morning of the 21st of June, we were on our way to the summit of the volcano. M. Le Gros, whose attentions were unwearied, M. Lalande, secretary to the French Consulate at Santa Cruz, and the English gardener at Durasno, joined us on this excursion. The day was not very fine, and the summit of the peak, which is generally visible at Orotava from sunrise till ten o'clock, was covered with thick clouds.
We were agreeably surprised by the contrast between the vegetation of this part of Teneriffe, and that of the environs of Santa Cruz.
Under the influence of a cool and humid climate, the ground was covered with beautiful verdure; while on the road from Santa Cruz to Laguna the plants exhibited nothing but capsules emptied of their seeds. Near the port of Santa Cruz, the strength of the vegetation is an obstacle to geological research. We pa.s.sed along the base of two small hills, which rise in the form of bells.
Observations made at Vesuvius and in Auvergne lead us to think that these hills owe their origin to lateral eruptions of the great volcano. The hill called Montanita de la Villa seems indeed to have emitted lavas; and according to the tradition of the Guanches, an eruption took place in 1430. Colonel Franqui a.s.sured Borda, that the place is still to be seen whence the melted matter issued; and that the ashes which covered the ground adjacent, were not yet fertilized. Whenever the rock appeared, we discovered basaltic amygdaloid* (* Basaltartiger Mandelstein. Werner.) covered with hardened clay,* (* Bimstein-Conglomerat. W.) which contains rapilli, or fragments of pumice-stone. This last formation resembles the tufas of Pausilippo, and the strata of puzzolana, which I found in the valley of Quito, at the foot of the volcano of Pichincha. The amygdaloid has very long pores, like the superior strata of the lavas of Vesuvius, arising probably from the action of an elastic fluid forcing its way through the matter in fusion.
Notwithstanding these a.n.a.logies, I must here repeat, that in all the low region of the peak of Teneriffe, on the side of Orotava, I have met with no flow of lava, nor any current, the limits of which are strongly marked. Torrents and inundations change the surface of the globe, and when a great number of currents of lava meet and spread over a plain, as I have seen at Vesuvius, in the Atrio dei Cavalli, they seem to be confounded together, and wear the appearance of real strata.
The villa de Orotava has a pleasant aspect at a distance, from the great abundance of water which runs through the princ.i.p.al streets.
The spring of Agua Mansa, collected in two large reservoirs, turns several mills, and is afterward discharged among the vineyards of the adjacent hills. The climate is still more refres.h.i.+ng at the villa than at the port of La Cruz, from the influence of the breeze, which blows strong after ten in the morning. The water, which has been dissolved in the air at a higher temperature, frequently precipitates itself; and renders the climate very foggy.
The villa is nearly 160 toises (312 metres) above the level of the sea, consequently 200 toises lower than the site on which Laguna is built: it is observed also, that the same kind of plants flower a month later in this latter place.
Orotava, the ancient Taoro of the Guanches, is situated on a very steep declivity. The streets seem deserted; the houses are solidly built, and of a gloomy appearance. We pa.s.sed along a lofty aqueduct, lined with a great number of fine ferns; and visited several gardens, in which the fruit trees of the north of Europe are mingled with orange trees, pomegranate, and date trees. We were a.s.sured, that these last were as little productive here as on the coast of c.u.mana. Although we had been made acquainted, from the narratives of many travellers, with the dragon-tree of the garden of M. Franqui, we were not the less struck with its enormous magnitude. We were told, that the trunk of this tree, which is mentioned in several very ancient doc.u.ments as marking the boundaries of a field, was as gigantic in the fifteenth century as it is at the present time. Its height appeared to us to be about 50 or 60 feet; its circ.u.mference near the roots is 45 feet. We could not measure higher, but Sir George Staunton found that, 10 feet from the ground, the diameter of the trunk is still 12 English feet; which corresponds perfectly with the statement of Borda, who found its mean circ.u.mference 33 feet 8 inches, French measure. The trunk is divided into a great number of branches, which rise in the form of a candelabrum, and are terminated by tufts of leaves, like the yucca which adorns the valley of Mexico. This division gives it a very different appearance from that of the palm-tree.
Among organic creations, this tree is undoubtedly, together with the Adansonia or baobab of Senegal, one of the oldest inhabitants of our globe. The baobabs are of still greater dimensions than the dragon-tree of Orotava. There are some which near the root measure 34 feet in diameter, though their total height is only from 50 to 60 feet. But we should observe, that the Adansonia, like the ochroma, and all the plants of the family of bombax, grow much more rapidly* than the dracaena, the vegetation of which is very slow.
(* It is the same with the plane-tree (Plata.n.u.s occidentalis) which M. Michaux measured at Marietta, on the banks of the Ohio, and which, at twenty feet from the ground, was 15.7 feet in diameter.
--”Voyage a l'Ouest des Monts Alleghany” 1804 page 93. The yew, chestnut, oak, plane-tree, deciduous cypress, bombax, mimosa, caesalpina, hymenaea, and dracaena, appear to me to be the plants which, in different climates, present specimens of the most extraordinary growth. An oak, discovered together with some Gallic helmets in 1809, in the turf pits of the department of the Somme, near the village of Yseux, seven leagues from Abbeville, was about the same size as the dragon-tree of Orotava. According to a memoir by M. Traullee, the trunk of this oak was 14 feet in diameter.) That in M. Franqui's garden still bears every year both flowers and fruit. Its aspect forcibly exemplifies ”that eternal youth of nature,” which is an inexhaustible source of motion and of life.
The dracaena, which is seen only in cultivated spots in the Canary Islands, at Madeira, and Porto Santo, presents a curious phenomenon with respect to the migration of plants. It has never been found in a wild state on the continent of Africa. The East Indies is its real country. How has this tree been transplanted to Teneriffe, where it is by no means common? Does its existence prove, that, at some very distant period, the Guanches had connexions with other nations originally from Asia?* (* The form of the dragon-tree is exhibited in several species of the genus Dracaena, at the Cape of Good Hope, in China, and in New Zealand. But in New Zealand it is superseded by the form of the yucca; for the Dracaena borealis of Aiton is a Convallaria, of which it has all the appearance. The astringent juice, known in commerce by the name of dragon's blood, is, according to the inquiries we made on the spot, the produce of several American plants, which do not belong to the same genus and of which some are lianas. At Laguna, toothpicks steeped in the juice of the dragon-tree are made in the nunneries, and are much extolled as highly useful for keeping the gums in a healthy state.)
On leaving Orotava, a narrow and stony pathway led us through a beautiful forest of chestnut trees (el monte de Castanos), to a site covered with brambles, some species of laurels, and arborescent heaths. The trunks of the latter grow to an extraordinary size; and the flowers with which they are loaded form an agreeable contrast, during a great part of the year, to the Hyperic.u.m canariense, which is very abundant at this height. We stopped to take in our provision of water under a solitary fir-tree. This station is known in the country by the name of Pino del Dornajito. Its height, according to the barometrical measurement of M. de Borda, is 522 toises; and it commands a magnificent prospect of the sea, and the whole of the northern part of the island. Near Pino del Dornajito, a little on the right of the pathway, is a copious spring of water, into which we plunged the thermometer, which fell to 15.4 degrees. At a hundred toises distance from this spring is another equally limpid. If we admit that these waters indicate nearly the mean heat of the place whence they issue, we may fix the absolute elevation of the station at 520 toises, supposing the mean temperature of the coast to be 21 degrees, and allowing one degree for the decrement of caloric corresponding under this zone to 93 toises. We should not be surprised if this spring remained a little below the heat of the air, since it probably takes its source in some more elevated part of the peak, and possibly communicates with the small subterranean glaciers of which we shall speak hereafter. The accordance just observed between the barometrical and thermometrical measures is so much more striking, because in mountainous countries, with steep declivities, the springs generally indicate too great a decrement of caloric, for they unite small currents of water, which filtrate at different heights, and their temperature is consequently the mean between the temperature of these currents. The spring of Dornajito has considerable reputation in the country; and at the time I was there, it was the only one known on the road which leads to the summit of the volcano. The formation of springs demands a certain regularity in the direction and inclination of the strata.