But the principal tribe, and that which subsequently spread throughout Greece, after filling with population the valley of the Haliacmon, traversing the Caulavian range, and descending along the course of the Aoös, seem on the banks of the Celydnos, to have turned their faces southward. Following that stream upwards towards its source, they found themselves in Epeiros, a land abounding with water brooks, with lovely mountains, and lovelier valleys, and at length settled, and erected themselves lasting habitations in the sacred neighbourhood of Dodona,[18] where the first oracle known to the Hellenes flourished under the protection of the Pelasgian Zeus.[19] Footnote 18: Strab. vii. 7. p. 124. seq. Hesiod. Frag. 54. et 124. Gœttl.—A second Dodona is supposed to have existed in Thessaly.—See Thirl. Hist. of Greece, i. 36.—Cf. Buttm. Diss. de orac. Dodon. Orat. Att. vii. 133. sqq. Footnote 19: Il. π. 233. Up to this point we have been treading, with little or no light to guide us, over a soil shifting, unsure, and treacherous; but here we touch upon comparatively firm ground, while the light of poetry dawns around, and enables us to direct our footsteps towards the luminous terra firma of history. It must not be denied that much of the foregoing theory is erected on inference and conjecture. Nevertheless, it rests in part on facts which an historian ought not to reject. For example, though it be nowhere, perhaps, distinctly stated that the Thracians were entirely of Pelasgian origin, we are compelled by various circumstances to believe that such was the case: first, Samothrace on the coast was undoubtedly peopled by Pelasgi;[20] secondly, the Macedonians, plainly of the same stock with the Thracians, are acknowledged to have been Pelasgi;[21] and since the Illyrians likewise were a kindred people,[22] we have a line of Pelasgian settlements stretching along the whole northern frontier of Greece, the Ægæan, the Hellespont, and the Propontis, from the Adriatic to the Black Sea. The chain of proofs, indeed, is not complete, but appears and disappears alternately, like the stream of the Alpheios, though little doubt can be entertained of the existence of the links which happen to lie out of sight. In nearly every part of Macedonia the footsteps of the Pelasgi are clearly discernible; at Crestona,[23] on the Echidoros in Pœonia; in Emathea, and Bottiœa;[24] and looking at the language of the country, we find it at all times to have been identical with that of Greece. That the same thing must be predicated of Thrace, even in the remotest ages, appears indisputably from this, that her bards, Thamyris and Orpheus traversed the whole of Hellas, and sang their wisdom to its inhabitants; while Olen coming from Lycia, a Pelasgian settlement,[25] likewise brought his kindred songs to the same tolerant and hospitable land. Footnote 20: Herod. ii. 51. Footnote 21: Justin. vii. 1. Thucyd. ii. 99. Footnote 22: Müller, Dor. i. 2.