upon the hardest bodies, upon stones and rocks, to which they adhere by a base of great tenacity, or rather are cramped by means of a sort of branched claw, very different from a root, although having its appearance. These claws are not destined to draw from a soil which they cannot penetrate, alimentary juices which are to be carried to the upper parts of these vegetables; for these parts, being entirely immersed in the same medium, equally absorb, by the whole of their surface, the principles of their nutrition, and we have not as yet been able to discover the ascent of any liquid, such as sap, &c. Marine plants have, besides a foliage which is plane or divided into filaments, of a pliant texture, a coriaceous or membranaceous structure, susceptible of accommodating itself to all the motions of the water in which it is immersed, without receiving any injury.

Although their mode of fructification is still little known, it appears that their seeds, or what they have in place of them, are very glutinous; that they attach themselves indifferently to all solid bodies, and cover the rocks with a vegetation equally abundant, and not less agreeable than that of the swards which carpet our mountains. It is true they do not expand brilliant corollæ, nor fill the air with their perfumes, but they often present, in the form, variety and mixture of the colours of their foliage, an aspect not less seducing.

It would be difficult to say what are the circumstances favourable or hurtful to their multiplication; but if we examine the rocks which it is permitted us to approach, we shall find them covered with a rich vegetation. It is to be supposed that these plants, although placed in the same general medium, are, equally with terrestrial plants, subjected to the influence of localities, depths and temperature, since there are some which only shew themselves in certain seas, which are met with, for instance in the Atlantic, while they are not to be seen in the Mediterranean, which occur in the Indian Ocean, while they are denied to the frozen seas of the north, &c. Others grow at such depths that we are only acquainted with them by means of their fragments.

I shall not follow further in her great works, Nature incessantly occupied in laying everywhere the foundations of vegetation. What I have said will suffice to present an idea of all the

resources which she employs to overcome obstacles, and diffuse motion and life throughout. We have followed her in the plains, upon the mountains, in the moving sands, and in the very bosom of the waters. If we now descend into the cavities where the light never penetrates, we shall there find peculiar plants, destined to dwell in darkness, such as certain species of rhizomorphæ, byssi, &c. In short there are no substances, whether contained in the open air, or in the waters, laid open to the light, or concealed in the most obscure recesses, exposed to humidity or to dryness, which are not occupied by plants adapted for these different localities. The moulds attack all our alimentary provisions, when they are left undisturbed and kept in damp places; numerous fungi, enormous boleti, grow in the shade upon plants in a state of putrefaction; lichens and mosses penetrate the wrinkled bark of trees; a multitude of animals of a very inferior order, such as larvæ of insects, worms, mollusca, whether naked or testaceous, crustacea, arachnidæ, establish their abode in the midst of this growing vegetation; they deposit their offspring there, live in abundance, like our herds in the pastures, enjoy the coolness and the shade, like the great animals in their forests. In this manner is propagated the sublime work of creation in those organic beings which contribute, during their life, by their secretions, and after their death by their spoils, to the augmentation of vegetable earth, and of many other inorganic substances.

Observations made during a Visit to Madeira, and a Residence in the Canary Islands. By Baron LEOPOLD VON BUCH. (Continued from former volume, p. 380.)

AT this we were much surprised. We did not imagine we had climbed to such a height, and we thought that it was impossible to ascend so high in Madeira. The accounts of the height of Pico Ruivo, which is by far the highest mountain on the island, stood far below our calculation of the height of Toringas. Dr Thomas Heberden (a brother of Dr William Heberden, to whom we are indebted for the remarkable obser

vations upon the increasing quantity of rain accumulated near the surface, in other respects an accurate individual) mentions that he, by barometrical observations, according to De Luc's formula, had calculated the height of Pica Ruivo at 4825 French feet. The barometer was not observed by himself, however, but by some English travellers, whom he does not name. He does not give the barometrical height, but merely the result, (Phil. Trans. lv. 126). This measurement may, therefore, be considered somewhat doubtful. Two later observers, instead of removing this doubt, have only increased it. The celebrated Captain Sabine saw the barometer on the summit of Pico Ruivo on 13th June 1822, 23° In., 4.54 Lin. par. therm. 1°.8 R : In Funchal 75 feet above the sea, 28.6,-33,-13.1; which gives the mountain an elevation of 5011 French feet.

Bowdich had ascended the mountain about the same time, and had seen the barometer at a height of 22° In., 10°.7 Lin. par therm., 7.5 R: In the house of the Consul Veitch, at Funchal, 28.-5,6,-16.4. This house lies 145 feet above the sea; the top of the mountain is therefore 5788 French feet, 304 feet more than Cima de Toringa, according to one account, (Jameson's Edin. Journal, xviii. 317.) There can be no doubt of the greater height of Pico Ruivo; and there being little probability of error in the continued series of our observations, I consider that Bowdich's measurement, contained in his letter to Jameson, is to be preferred.

Towards the evening of Tuesday 2d May, we left Funchal and Madeira. The wind carried us tediously along. The captain, however, on the 4th, told us that he saw the Peak. He saw it with a seaman's eye from the tint of the atmosphere above it. It was not visible to us; but early on the 5th, Teneriffe was completely spread out before us. At the distance of about twenty-seven miles, the Peak rose above the clouds, vast and majestic; and the snow was seen lying upon its declivity, and descending almost to the woods; while the people were busily engaged with the wheat harvest, on the gently sloping shore of Tacaronte. At length Orotava appeared beneath the clouds of the Peak, as Frascati does from Rome, and a distinct stream of lava stretching from the Peak towards the

harbour, could be seen by the eye, among plants and layers of white pumice.

On 6th May, at 10 A. M., we landed at Puerto Orotava. To render our stay on this island ever worthy of remembrance, it was scarcely necessary to be admitted to the hospitality of (Barry and Bruce), one of the most intelligent, amiable, and polite families in the town. When evening recalled us from our excursions in the neighbourhood, we hastened home, to find there united every thing that genius, intelligence, fine feeling, and Spanish warmth of temperament, could produce. Having thus explored the woods above Villa Orotava, the rocks of St Ursula, Ria Lejo, La Rambla, the environs of Garachico and Icod, we at length, on the 18th May, undertook to ascend the Peak.

Being tolerably intimate with the works of other travellers, we did not stop by the way to discover new phenomena unobserved by others, but to discover some traces of what we found related in these old accounts. We hence expected, after leaving the beautiful chesnut wood above Villa Orotava, to meet with the woods of pines, which Humboldt supposed were certainly a new species, hitherto undescribed, (Rel i. 186.) We saw only the celebrated Pino del Dornajito, the only one that appeared the whole way. Still it is certain, that their way to the foot of the peak was through a thick wood of trees of this description. This was the case at the beginning of the last century; and according to the observation of Edens and P. Feuillé, the ascent in this wood, through pine trees of striking shape and size, was divided into several sections, the Pino de la Caravela, and higher, the Pino de la Merienda. These the destructive axe has not spared; and the Pino del Dornajito, the only one the whole way up, owes its preservation solely to the spring which it overshadows. At present there is no trace of the pine-trees, and the ground is covered with small bushes of heath and plants of fern. At present, we meet with no object, which, like a pillar, could point out the path; and we perceive, with surprise, that we have spent a number of hours in climbing from the chesnuts to Portillo, by a road over which we do not appear to make the least progress, by reason of the uniformity of the objects around it.

It is otherwise, when we actually arrive at the foot of the Peak, through the defiles of Portillo. Here we felt as if again placed amidst the sublime stillness and solitude of the glaciers of the Alps, and, as in the Alpine glaciers, the traveller, in wandering over the boundless and gently rising acclivities of pumice, becomes bewildered. What seemed mere blocks at a distance, became rocks when we approached them; and crater hills were transformed into imposing mountains. No scale of the plain could yet be applied. The mass of the peak stood still higher above this level than we had yet seen it; and black streams of glass descended from the summit like ribbands upon the declivity. Continually occupied with the vast spectacle, we were not sensible that we were obliged to travel three hours longer to reach the margin of the stream of lava. Some of the large blocks that compose this margin, are so thrown together as to form benches and apartments of a rude description, among which people commonly wait till the following morning, before they prosecute their journey farther. It is the lower Estancia de los Ingleses.

The ascent from this is difficult; and still more so, when, at an additional elevation of 2000 feet, we must actually cross a black sharp field of glass; although it is never to be compared to the labour of climbing to some of the summits of the Alps. Upwards, above Cueva del Hielo, about 10,300 feet above the sea, we observed the first flakes of snow upon the declivity. They were but small; and in our farther approach towards the summit, we saw no more of them. Bewildered in looking upon the boundless prospect, which astonishes, rather than delights or elevates, because the imagination, unsatisfied with the surrounding shapeless horizon, looks back on it with horror; we had been already some hours upon the margin, and in the interior of the crater, when Mrs Hammond, a Scotch lady, with her company, appeared above, the first female, who, in the memory of the inhabitants, ever ascended the peak. They went round the whole crater, and likewise round that side towards Chahorro, which is so seldom visited; and although the sharp obsidian cut their shoes and feet in a dreadful manner, they did not hesitate to visit along with us the natural ice-pits between the blocks of obsidian and the Cueva del Hielo, which, during the