Let us first direct our attention to landmarks and beacons; by which, in nautical language, we mean every terrestrial object that assists the seaman in calculating his data, and determining his course. The spires of churches, the towers of castles, windmills, tall isolated trees, or rocks of a characteristic configuration, are useful for this purpose. Solitary peaks, like that of Teneriffe—volcanoes surmounted by a canopy of smoke—are gigantic landmarks which assist the navigator in rectifying his geographical position. Among the very numerous class of landmarks we meet with a few as celebrated as, or even more celebrated than, the majority of our lighthouses. Such are the Pillars of Hercules—anciently designated the Columns of Saturn or of Briareus—and Pompey’s Pillar, near Alexandria. One thing is wanting, however, to the glory of the Pillars of Hercules—that they should have existed. Hesychius, nevertheless, asserts that there were three or four, while, according to Edrisi, six were placed on the sea-coast; the easternmost at Cadiz, in Andalusia; the others in the islands of the Shadowy Seas, as a warning to navigators not to advance beyond them. But Strabo, when speaking of the foundation of Cadiz by the Tyrians, puts forward some doubts as to the accuracy of this statement, and his doubts seem not to have been ill-founded. We believe with him that these famous Pillars of Hercules existed only in the imagination of the writers of antiquity, who were frequently as enthusiastic in belief of fable as of truth. The best known sites of the pillars, whether they were real or fabulous, were at Calpe, on the European shore of the Straits of Gibraltar, and at Abyla, on the African. But _what_ the pillars were, none of the ancient authorities are agreed. According to Strabo, some believed them to be rocky headlands, others, islands; the former rising up from the land, the latter starting out of the sea, like gigantic columns. Others, again, understanding the word στῆλαι literally, looked for artificial mounds, or columns, or statues, which Hercules himself had erected to indicate the limit of his conquests, or the Phœnician navigators had dedicated to their tutelary deity, to record the extent of their discoveries.[60] Strabo informs us that this literal interpretation was held by the Iberians and Libyans, who denied that there existed at the Straits anything resembling columns, but pointed out, as the Pillars of Hercules, the bronze columns in the temple of the god at Gades, on which the expenses of building the temple were inscribed. He adds that this opinion was held by Poseidonius, in opposition to the Greeks in general, who considered the pillars to mean _promontories_. [60] See Article “Herculis Columnæ,” in Smith’s “Dictionary of Geography,” i. 1054. * * * * *