It has been my fortune to pass these straits on three several occasions when they were perfectly calm. During the passage from Corsica in an open boat, which I am now relating, there was so little wind that, with all the spread of high-peaked sails a Mediterranean boat can carry, we made but little way, and the surface was so unruffled that my friend was able to sketch at ease the out-line of the Corsican mountains, from which we were slowly receding.

It was, however, pleasurable to linger midway between the two islands, retracing our route in the one by the lines of its mountain ranges, and anticipating fresh delight in penetrating those of the Gallura now in prospect.

The appearance of a French revenue cutter to windward tended to reconcile us to the failure of our plan of getting smuggled across the straits, which might have led to more serious consequences than the detention we suffered.

The coast line on both sides of the channel, as on all the shores of the two islands, is remarkably bold ; and the scene was diversified by the groups of rocky islets scattered across the straits, and described in a former chapter as the broken links of a chain which once united Corsica with the mountain system of the north-east portion of the island of Sardinia. They are composed entirely of a fine-grained red granite.

In some of the islets lying nearest the Corsican coast quarries were worked to supply blocks and columns for the temples and palaces of imperial Home. Quarries of the same material were also worked by the Romans, as we shall find presently, on the coast of Sardinia, opposite these islands.

With two exceptions, these “Intermediate Islands” are uninhabited. They were considered of so little importance that, till the middle of the last century, it was considered a question which of them belonged to Sardinia and which to Corsica. It was then easily settled by drawing a visual line equidistant from Point Lo Sprono on the latter, and Capo Falcone on the former; it being agreed that all north of this line should belong to Corsica, and all south of it to Sardinia. The distance between the two capes is about ten nautical miles.

The Capes Falcone, with La Marmorata close by, and La Testa forming the north-west point of Sardinia, are all of the same formation as the rocky islands in the straits already mentioned, and, like them, this district furnished the Romans with many of the granite columns which still form magnificent ornaments of the Eternal City.

Those of the Pantheon are said to have been excavated near Longone; and several similar ones, as well as rude blocks, may still be seen in the quarries on the promontory of Santa Reparata, near which the remains of some Roman villas have also been discovered. In later days we find the value of the Gallura granite appreciated by the Pisans.

Their Duomo, built by Buschetto in 1063, soon after their possession of Sardinia, shows the beauty of the Marmorata rocks; and the Battisterio, built in 1152 by Dioti Salvi, has also much of Gallura material in its construction.