The quarries of granite and porphyry which supplied the Romans in the time of Trajan, were discovered by Sir Gardner Wilkinson and Mr Burton, in the years 1821-22, at Djebel-Fattereh and Djebel-Dokhan; and Monsieur Letronne has pointed out the connexion of these quarries with the improvements made by Trajan in the canal.[1] Many large works of porphyry exist, which must have been worked in the quarries of Djebel-Dokhan. We need only enumerate the great porphyry vase in the Vatican, which exceeds fourteen feet in diameter--that of the museum at Naples, which is cut out of a block nearly as large--the tombs of St Helen in the Vatican, and of Benedict XIII. in St John Lateran--and the blocks of the porphyry column at Constantinople. It is evident that the masses could never be conveyed from Djebel-Dokhan to the Nile by land; but no great difficulty would be found in transporting them to Myos Hormos on the Red Sea, and embarking them there for Arsinoee; from whence their conveyance to Alexandria, by the canal and the Nile, was easy. It is well known that the quarries of porphyry in Egypt could not have grown into importance until after the reign of Claudius, as Vitrasius Pollio sent the first porphyry statues which had been seen at Rome as a present to that emperor.[2] The chief, if not the only quarries of red porphyry known to the ancients were in the Thebaid, at Djebel-Dokhan. [1] Journal of the Royal Geographical Society, vol. ii. [2] Plinii Natur. Hist. xxxvi. 11. At the granite quarries of Djebel Fattereh, Sir Gardner Wilkinson found many columns in various stages of completion, some ready to be removed; and of these there were several of the enormous size of fifty-five feet long, and nearly eight feet in circumference. These quarries are at least thirty miles distant from the Red Sea; but, as the ground affords a continual descent, and some traces of the road exist, there cannot be a doubt that these immense columns were destined to be carried to Philotera, and there shipped for Arsinoee, and that, like the porphyry vases, they were to find their way to Rome, by the canal, the Nile, and the port of Alexandria. Sir Gardner Wilkinson has shown that these granite quarries were abandoned not long after the reign of Hadrian; and an inscription, quoted by Letronne, proves that the granite quarries at Syene were first worked about the years A.D. 205-209. The great facilities afforded by the Nile for transporting the largest columns from Syene to Alexandria, appears to have caused the immediate abandonment of the quarries of Djebel Fattereh; as the expense of transporting the columns already finished was doubtless greater than the cost of working and conveying new ones from Syene to Alexandria.