At first they were content with the nearer reaches of the Indian Ocean, and with the more eastern parts of the Mediterranean. But gradually they wandered farther. Colony after colony was planted beyond Egypt, till they reached the Pillars of Hercules, known to us as the Straits of Gibraltar, to face a wild and strange Ocean, full of mystery. There they made a startling discovery, enough to impress the more thoughtful minds among them. Far to the east, in the “Indian Ocean” of our days, their sailors had been acquainted with high and low tides; while throughout the Mediterranean scarcely any tides existed. But in the open sea, outside the narrow Channel, they found the very same tidal changes as in the eastern ocean. It is hardly to be supposed that any one of them had a mind of such far-seeing grasp that he should be able to conjecture the grand truth of eastern and western oceans being ONE--swayed by the same influences, governed by the same laws. A Phenician of those days, catching a glimpse of this truth, would have been worthy to take rank beside our Sir Isaac Newton of after days. They are believed to have observed the coincidence; no doubt with a feeling of wonder; and probably it was to them merely a coincidence. Very little was then understood of the most everyday and commonplace workings of Nature. Not much, indeed, can be said with certainty of what the Phenicians did truly discover. Some observations they must have made of the heavenly constellations; and the Pole-star at least must have been known to them, otherwise it is impossible to imagine how they could have steered their vessels at night, in an age when the Mariner’s Compass was unknown. They are supposed to have sailed far south on the west coast of Africa, if they did not actually round the Cape of Good Hope. It does not appear that their knowledge was passed on to the Greek nation. Either they were curiously reticent of what they knew, or else such records as they may have left were destroyed and forgotten. In after times the Carthaginians, descendants of Phenician Colonists, were, like their forefathers, sea-lovers, sea-explorers, searching the main, not as travellers search now from pure love of knowledge, or from a liking for adventure, but for the sake of commerce. The Carthaginians, however, instead of being able to make use of previous discoveries, and to work onwards from a point already gained, had to start afresh and to find their way--just as if it had never been found before--to and beyond the Pillars of Hercules. To the Greek imagination that wide mysterious Ocean, opening out from the narrow Strait, was unattractive and terrible. It was a sea of limitless distances, of fog and gloom, of blackness and death; not an unexplored Ocean of possible glory and beauty and wealth.