Page:The geography of Strabo (1854) Volume 1.djvu/99

CHAP. in. 11. INTRODUCTION. 85 he professes himself a mathematician, 1 he rejects entirely the dictum of Archimedes, who, in his work " On Bodies in Suspen- sion," says that all liquids when left at rest assume a spherical form, having a centre of gravity similar to that of the earth. jTdictum which is~acknowledged by all who have the slight- est pretensions to mathematical sagacity. He says that the Mediterranean, which, according to his own description, is one entire sea, has not the same level even at points quite close to each other ; and offers us the authority of engineers for this piece of folly, notwithstanding the affirmation of mathe- maticians that engineering is itself only one division of the mathematics. He tells us that Demetrius 2 intended to cut through the Isthmus of Corinth, to open a passage for his fleet, but was prevented by his engineers, who, having taken measurements, reported that the level of the sea at the Gulf of Corinth was higher than at Cenchrea, 3 so that if he cut through the isthmus, not only the coasts near ^Egina, but even JEgina itself, with the neighbouring islands, would be laid completely under water, while the passage would prove of little value. According to Eratosthenes, it is this which occasions the current in straits, especially the current in the Strait of Sicily, 4 where effects similar to the flow and ebb of the tide are remarked. The current there changes twice in the course of a day and night, like as in that period the tides of the sea flow and ebb twice. In the Tyrrhenian sea 5 the current which is called descendent, and which runs to- wards the sea of Sicily, as if it followed an inclined plane, corresponds to the flow of the tide in the ocean. We may remark, that this current corresponds to the flow both in the time of its commencement arid cessation. For it commences at the rising and setting of the moon, and recedes when that satellite attains its meridian, whether above [in the zenith] or below the earth [in the nadir]. In the same way occurs the opposite or ascending current, as it is called. It corresponds to 1 We have here followed the earlier editions, as preferable to Kramer, who supplies firi before fJ.a9rjnaTiKOQ. 2 Demetrius Poliorcetes : the same intention is narrated by Pliny and other historians of Julius Caesar, Caligula, and Nero. 3 Kankri. 4 Strait of Messina. 4 The sea which washes the shores of Tuscany. Strabo applies the term to the whole sea from the mouth of the Arno to Sicily.