Then one comes to a large harbor, which is called Bathys Limen;Deep Harbor. then to Aulis, a rocky place and a village of the Tanagraeans. Its harbor is large enough for only fifty boats; and therefore it is reasonable to suppose that the naval station of the Greeks was in the large harbor. And near by, also, is the Euripus at Chalcis, to which the distance from Sunium is six hundred and seventy stadia; and over it is a bridge two plethra long,In 411 B.C. Chalcis was joined to the mainland by a bridge. Moles were thrown out into the Euripus from each shore, high towers were built at the ends of the two moles, leaving a passage through for a single ship, and "wooden bridges were set over the channels" (Diod. Sic. 13.47). The plurals "bridges" and "channels" may be explained by the fact that there was a small rocky island in the middle of the strait between the two channels. In 334 B.C. they fortified the bridge with towers and gates and a wall, and included the Boeotian Mt. Canethus (Karababa?) as a bridgehead within the circuit of the city of Chalchis (Strabo 10. 1. 8). Chalcis was still joined to the continent by a bridge in 200 B.C. (Livy 28.6), and Aemilius Paulus went to see it about 167 B.C. (Livy 45.27). And there was still a bridge there in the time of Livy himself, although the tower mentioned by him (28. 6) was no longer there (note the tense of claudebat). Strabo's "two plethra" (202 feet) is accurate enough for the entire stretch across the strait, and he must have included the moles in his term "bridge." Today the western channel is entirely closed, while the eastern is spanned by a swing-bridge about 85 feet long. as I have said;9. 2. 2 and a tower stands on each side, one on the side of Chalcis, and the other on the side of Boeotia; and tube-like passages have been constructed into the towers.The usual interpretation of this clause, "a canal (σῦριγξ) has been constructed between (εἰς) the towers" seems impossible. The literal translation is "a tube has been constructed across into them" (the towers). Bréquigny (quoted in the French trans., vol. iii, x, appears to be on the right track: "On y a pratique des σῦριγξ (souterrains) pour y communiquer" ("they have constructed subterranean passages so as to communicate with the towers"). Livy 28.6 says: "The city has two fortresses, one threatening the sea, and the other in the middle of the city. Thence by a cuniculum (literally, "rabbit-hole," and hence a" tube-like passageway") "a road leads to the sea, and this road used to be shut off from the sea by a tower of five stories, a remarkable bulwark." Certainly σῦριγξ should mean an underground passage or else a roofed gallery of some sort above the ground (cf. the use of the word in Polybius 9. 41.9 concerning the investment of Echinus by Philip, and in 15. 39. 6); and Strabo probably means that there was a protected passage across to the towers from both sides. See Leake's , II, 259; Grote's , VIII, ch. 63; and the discussion by the French translators (l. c.), who believe that there were two passages for ships, one on each side of the strait. Concerning the refluent currents of the Euripus it is enough to say only thus much, that they are said to change seven times each day and night;"They take place, not seven times in the twenty-four hours, as Strabo says, but at irregular intervals" (Tozer, , p. 234). See the explanation of Admiral Mansell in Murray's , pp. 387-388. but the cause of the changes must be investigated elsewhere.