MARSHKS AND LAKES. 219
- jf 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 interest- ing remnants of antiquity, since it must date from the prosperous days of the old Orchomenus, anterior to its absorption into the Boeotian 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 Bceotia, and ultimately by his early death. 1 The Katabothra of the lake Kopai's, are a specimen of the phenomenon so frequent in Greece, lakes and rivers finding for themselves subterranean passages through the cavities in the limestone rocks, and even pursuing their unseen course for a considerable distance before they emerge to the light of day. In Arcadia, especially, several remarkable examples of subterranean water communication occur ; this central region of Peloponnesus presents a cluster of such completely inclosed valleys, or basins. 9 ' Strabo, ix. p. 407. 2 Colonel Leake observes (Tiavels in Morea, vol. iii. pp. 45, 153-155), " The plain of Tripolitza (anciently that of Tegea and Mantineia) is by far the greatest of that cluster of valleys in the centre of Peloponnesus, each of which is so closely shut in by the intersecting mountains, that no outlet is afforded to the waters except through the mountains themselves," etc. Re- specting the Arcadian Orchomenus, and- its inclosed lake with Katabothra, see the same work, p. 103 ; and the mountain plains near Corinth, p. 263. This temporary disappearance of the rivers was familiar to the ancient observers oi Ka-airivonevot TUV irordpuv. (Aristot. Meteorolog. i. 13. Dio- dor. xv. 49. Strabo, vi. p. 271 ; viii. p. 389, etc.) Their familiarity with this phenomenon was in part the source of some geographical suppositions, which now appear to us extravagant, respecting the long subterranean and submarine course of certain rivers, and their re- appearance at very distant points. Sophokles said that the Inachus of Akar- nania joined the Inachus of Argolis: Ibykns the poet affirmed that the Asopus, near Sikyon, had its source in Phrygia ; the river Inopus of the little island of Delos was alleged by others to be an effluent from the mighty ^file ; and the rhetor Zoilns, in a panegyrical oration to the inhabitants of Tenedos, went the length of assuring them that the Alpheius in Elis had it ource in their island (Strabo, vi. p. 271). Not only Pindar and other poets (Antigon. Caryst. c. 155), but also the histonan Timaeus (Tima?i Frag. 127
