I was told in a bookseller's shop into which I had gone in search of a Geography of the island, that there was one then in the press, and that its author was Francesco Marmocchi, a banished Florentine. I immediately sought this gentleman out, and made in him one of the most valuable of all my Italian acquaintances. I found a man of prepossessing exterior, considerably above thirty, in a little room, buried among books. Possibly the rooms of most political exiles do not present such a peaceful aspect. On the bookshelves were the best classical authors; and my eye lighted with no small pleasure on Humboldt's Cosmos; on the walls were copperplate views of Florence, and an admirable copy of a Perugino; all this told not only of the seclusion of a scholar, but of that of a highly cultivated Florentine. There are perhaps few greater contrasts than that between Florence and Corsica, and my own feelings were at first certainly peculiar, when, after six weeks' stay in Florence, I suddenly exchanged the Madonnas of Raphael for the Corsican banditti; but it is always to be remembered that Corsica is an island of enchanting beauty; and though banishment to paradise itself would remain banishment, still the student of nature may at least, as Seneca did, console himself here with the grandeur and beauty around him, in undisturbed tranquillity. All that Seneca wrote from his Corsican exile to his mother on the consolation to be found in contemplating nature, and in science, Francesco Marmocchi may fully apply to himself. This former Florentine professor seemed to me, in his dignified retirement and learned leisure, the happiest of all exiles.
Francesco Marmocchi was minister of Tuscany during the revolution, along with Guerazzi; he was afterwards secretary to the ministry: more fortunate than his political friend, he escaped from Florence to Rome, and then from Rome to Corsica, where he had already lived three years. His unwearied activity, and the stoical serenity with which he bears his exile, attest the manly vigour of his character. Francesco Marmocchi is one of the most esteemed and talented Italian geographers. Besides his great work, a Universal Geography in six quarto volumes, a new edition of which is at present publishing, he has written a special Geography of Italy in two volumes; a Historical Geography of the Ancient World, of the Middle Ages, and of Modern Times; a Natural History of Italy, and other works. I found him correcting the proof-sheets of his little Geography of Corsica, an excellent hand-book, which he has unfortunately been obliged to write in French. This book is published in Bastia, by Fabiani; it has afforded me some valuable information about Corsica.
One morning before sunrise we went into the hills round Cardo, and here, amid the fresh bloom of the Corsican landscape, if the reader will suppose himself in our company, we shall take the geographer himself for guide and interpreter, and hear what he has to say upon the island. I give almost the very words of his Geography.
Corsica owes her existence to successive conglobations of upheaved masses; during an extended period she has had three great volcanic processes, to which the bizarre and abrupt contours of her landscape are to be ascribed. These three upheavals may be readily distinguished. The first masses of Corsican land that rose were those that occupy the entire south-western side. This earliest upheaval took place in a direction from north-west to south-east; its marks are the two great ribs of mountain which run parallel, from north-east to south-west, down towards the sea, and form the most important promontories of the west coast. The axis of Corsica at that time must therefore have been different from its later one; and the islands in the channel of Bonifazio, as well as a part of the north-east of Sardinia, then stood in connexion with Corsica. The material of this first upheaval is mostly granite; consequently at the period of this primeval revolution there was no life of any sort on the island.
The direction of the second upheaval was from south-west to north-east, and the material here again consists largely of granitoids. But as we advance to the north-east, we find the granite gradually giving way to the ophiolitic (ophiolitisch) earth system. The second upheaval is, however, hardly discernible. It is clear that it destroyed most of the northern ridge of the first; but Corsican geology has preserved very few traces of it.
The undoubted effect of the third and last upheaval was the almost entire destruction of the southern portion of the first; and it was at this time the island received its present form. It occurred in a direction from north to south. So long as the masses of this last eruption have not come in contact with the masses of previous upheavals, their direction remains regular, as is shown by the mountain-chain of Cape Corso. But it had to burst its way through the towering masses of the southern ridge with a fearful shock; it broke them up, altering its direction, and sustaining interruption at many points, as is shown by the openings of the valleys, which lead from the interior to the plain of the east coast, and have become the beds of the streams that flow into the sea on this side—the Bevinco, the Golo, the Tavignano, the Fiumorbo, and others.
The rock strata of this third upheaval are primitive ophiolitic and primitive calcareous, covered at various places by secondary formations.
The primitive masses, which occupy, therefore, the south and west of the island, consist almost entirely of granite. At their extremities they include some layers of gneiss and slate. The granite is almost everywhere covered—a clear proof that it was elevated at a period antecedent to that during which the covering masses were forming in the bosom of the ocean, to be deposited in horizontal strata on the crystalline granite masses. Strata of porphyry and eurite pierce the granite; a decided porphyritic formation crowns Mounts Cinto, Vagliorba, and Perturato, the highest summits of Niolo, overlying the granite. From two to three feet of mighty greenstone penetrate these porphyritic rocks.
The intermediary masses occupy the whole of Cape Corso, and the east of the island. They consist of bluish gray limestone, huge masses of talc, stalactites, serpentine, euphotides, quartz, felspar, and porphyries.
The tertiary formations appear only in isolated strips, as at San Fiorenzo, Volpajola, Aleria, and Bonifazio. They exhibit numerous fossils of marine animals of subordinate species—sea-urchins, polypi, and many other petrifactions in the limestone layers.