the ancient frontal moraine of the glacier represents, came to mark the limit of the domain of the Pacific. The freshness of the contours of the dead valleys of Patagonia bears witness to the recent date of this conquest, which was too sudden or rapid to be called a "capture" in the proper sense. It has not been accomplished everywhere. From Lake San Martin to Lake Buenos Aires all the lakes of the eastern slope are drained into the Pacific by rivers which flow into the Culen fiord. But further south, Lakes Viedma and Argentino are still tributaries of the Atlantic. They correspond to the zone of the Patagonian Andes which is still covered by inland ice. To the north, in the basin of the Puelo and the Yelcho, where the trans-Andean valleys long ago ceased to be obstructed by ice, the lakes of the eastern slope which drain toward the Pacific are small in size. Their level to-day is much lower than it used to be, and a network of streams has developed east of them, on the earlier lacustrine region, which is now dry. [Illustration: YOKE OF CREOLE OXEN USED FOR THE TRANSPORT OF TIMBER ON THE EASTERN CHACO, OR CHACO OF SANTA FE. _On the Central (or Santiago) Chaco mules are used for transport._ Photograph by the Author.] [Illustration: WORKS AT TARTAGAL (EASTERN CHACO) FOR MAKING TANNIC ACID. _These works, built by powerful firms, are permanent centres, drawing timber from a great stretch of forest, while the saw-mills of the Central Chaco move about freely, to be near the felling sites._ Photograph by the Author. PLATE XII. To face p. 128.] Pastoral colonization has now spread over almost the entire surface of Patagonia. The parts that are not yet occupied are of slight extent; they consist only of the most desolate regions in the south of the Rio Negro district and north of Santa Cruz. The expansion of white colonization began only about 1880. Until then the interior was abandoned to the indigenous tribes and was almost entirely unknown. The Atlantic coast alone had been explored. The travels of Villarino along the Rio Negro and the Limay as far as Lake Nahuel Huapi had left only a faded memory.[56] North of the Rio Negro, Woodbine Parish (1859), making use of the notes left by Cruz, who had crossed the Andes and the Indian territory between Antuco and Melincue in 1806, was the first to publish definite information, to which no addition would be made during the next forty years.[57] [56] _Diario de D. Basilio Villarino del reconocimiento que hizo del Rio Negro en el ano de_ 1782 (Coll. de Angelis, vi). [57] It is Woodbine Parish who corrects Villarino's mistake in confusing the Neuquen, at its confluence with the Limay, with the Rio Diamante, known in the south of the Mendoza province.