a sensible increase of the land at its embouchure, within the observation of Thucydidês.[333] [330] See Fiedler, Reise, etc. vol. i. pp. 84, 219, 362, etc. Both Fiedler and Strong (Statistics of Greece, p. 169) dwell with great reason upon the inestimable value of Artesian wells for the country. [331] Ross, Reise auf den Griechischen Inseln, vol. i. letter 2, p. 12. [332] The Greek language seems to stand singular in the expression χειμαῤῥοῦς,—the _Wadys_ of Arabia manifest the like alternation, of extreme temporary fulness and violence, with absolute dryness (Kriegk, Schriften zur allgemeinen Erdkunde, p. 201, Leipzig, 1840). [333] Thucydid. ii. 102. But the disposition and properties of the Grecian territory, though not maintaining permanent rivers, are favorable to the multiplication of lakes and marshes. There are numerous hollows and inclosed basins, out of which the water can find no superficial escape, and where, unless it makes for itself a subterranean passage through rifts in the mountains, it remains either as a marsh or a lake according to the time of year. In Thessaly, we find the lakes Nessônis and Bœbêis; in Ætolia, between the Achelous and Eunêus, Strabo mentions the lake of Trichônis, besides several other lakes, which it is difficult to identify individually, though the quantity of ground covered by lake and marsh is, as a whole, very considerable. In Bœotia, are situated the lakes Kopaïs, Hylikê, and Harma; the first of the three formed chiefly by the river Kephisus, flowing from Parnassus on the north-west, and shaping for itself a sinuous course through the mountains of Phokis. On the north-east and east, the lake Kopaïs is bounded by the high land of Mount Ptôon, which intercepts its communication with the strait of Eubœa. Through the limestone of this mountain, the water has either found or forced several subterraneous cavities, by which it obtains a partial egress on the other side of the rocky hill, and then flows into the strait. The Katabothra, as they were termed in antiquity, yet exist, but in an imperfect and half-obstructed condition. Even in antiquity, however, they never fully sufficed to carry off the surplus waters of the Kephisus; for the remains are still found of an artificial tunnel, pierced through the whole breadth of the rock, and with perpendicular apertures at proper intervals to let in the air from above. This tunnel—one of the most interesting remnants of antiquity, since it must date from the prosperous days of the old Orchomenus, anterior to its absorption into the Bœotian league, as well as to the preponderance of Thebes,—is now choked up and rendered useless. It may, perhaps, have been designedly obstructed by the hand of an enemy, and the scheme of Alexander the Great, who commissioned an engineer from Chalkis to reopen it, was defeated, first, by discontents in Bœotia, and ultimately by his early death.[334] [334] Strabo, ix. p. 407.