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islands. They are thirty-two feet long, three feet high at the gunwale, without decks, and generally carry from 200 to 250 quintals (181 to 226 cwts. avoirdupois). Although the sea is very rough from Cape Codera to La Guayra, and these boats have an enormous triangular sail, there had not been an instance for thirty years of the loss of one of them on the passage from Cumana to Caraccas, so great is the skill of the Guayqueria pilots. They descended the Manzanares with rapidity, delighted with the sight of its marginal cocoa-trees, and the glitter of the thorny bushes covered with noctilucous insects, and left with regret a country in which every thing had appeared new and marvellous. Passing at high water the bar of the river, they entered the Gulf of Cariaco, the surface of which was gently rippled by the evening breeze. In a short time the coasts were recognised only by the scattered lights of the Indian fishermen.

As they advanced towards the shoal that surrounds Cape Arenas, stretching as far as the petroleum springs of Maniquarez, they enjoyed one of those beautiful sights which the phosphorescence of the sea so often displays in tropical climates. When the porpoises, which followed the boat in bands of fifteen or sixteen, struck the surface of the water with their tails, they produced a brilliant light resembling flames. Each troop left behind it a luminous track; and as few sparks were caused by the motion of an oar or of the boat, Humboldt conjectured that the vivid glow produced by these cetaceous animals was owing, not to the stroke of their tails alone, but also to the gelatinous matter which envelops their bodies, and which is detached by the waves.

At midnight they found themselves among some rocky islets, rising in the form of bastions, and constituting the group of the Caraccas and Chimanas. Many of these eminences are visible from Cumana, and present the most singular appearances under

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ISLAND OF BORACHA.

the effect of mirage. Their height, which is probably not more than 960 feet, seemed much greater when enlightened by the moon, which now shone in a clear sky. The travellers were becalmed in the neighbourhood of these islands, and at sunrise drifted towards Boracha, the largest of them. The temperature had sensibly increased, in consequence of the rocks giving out by radiation a portion of the heat which they had absorbed during the day. As the sun rose, the cliffs projected their lengthened shadows on the ocean, and the flamingoes began to fish in the creeks. The insular spots were all uninhabited; but on one of them, which had formerly been the residence of a family of whites, there were wild goats of a large size and brown colour. The inhabitants had cultivated maize and cassava; but the father, after the death of his children, having purchased two black slaves, was murdered by them One of the assassins subsequently informed against his accomplice, and at the time of Humboldt's visit was hangman at Cumana.

Proceeding onwards, they anchored for some hours in the road of New-Barcelona, at the mouth of the river Neveri, which is full of crocodiles. These animals, especially in calm weather, occa sionally make excursions into the open sea,—a fact which is interesting to geologists, on account of the mixture of marine and fresh water organic remains that are occasionally observed in some of the more recent deposites. The port of Barcelona had at that time a very active commerce, arising from the demand in the West Indies for salted provision, oxen, mules, and horses; the merchants of the Havana being the principal purchasers. Its situation is extremely favourable for this exportation, the animals arriving in three days from the Llanos, while they take more than double that time to reach Cumana, on account of the chain of mountains which they have to cross. Eight thousand mules were

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embarked at Barcelona, six thousand at Porto Cabello, and three thousand at Carupano, in 1799 and 1800, for the several islands.

Landing on the right bank of the river, they ascended to a small fort, the Morro de Barcelona, built on a calcareous rock, at an elevation of about 400 feet above the sea, but commanded by a much higher hill on the south. Here they observed a very curious geological phenomenon, which recurred in the Cordilleras of Mexico. The limestone, which had a dull, even, or flat conchoidal fracture, and was divided into very thin strata, was traversed by layers of black slaty jasper, with a similar fracture, and breaking into fragments having a parallelopipedal form. It did not exhibit the little veins of quartz so common in Lydian stone, and was decomposed at the surface into a yellowish-gray crust.

Setting sail on the 19th at noon, they found the temperature of the sea at its surface to be 78.6°; but when passing through the narrow channel which separates the Piritoos, in three fathoms it was only 76 1°. These islands do not rise more than eight or nine inches above the mean height of the tide, and are covered with long grass. To the westward of the Morro de Barcelona and the mouth of the river Unare, the ocean became more and more agitated as they approached Cape Codera, the influence of which extends to a great distance. Beyond this promontory it always runs very high, although a gale of wind is never felt along this coast. It blew fresh during the night, and on the 20th, at sunrise, they were so far advanced as to be in expectation of doubling the cape in a few hours; but some of the passengers having suffered from sea-sickness, and the pilot being apprehensive of danger from the privateers stationed near La Guayra, they made for the shore, and anchored at nine o'clock in the Bay of Iliguerota, westward of the Rio Capaya.

On landing, they found two or three huts inhab