I have elsewhere[JN] given the natural history of the Condor, which before my travels had been variously misstated. The name is properly _Cuntur_ in the Inca language; _Mañque_ among the Araucanes in Chili; _Sarcoramphus Condor_ according to Duméril. I sketched the head of this bird from life, of the natural size, and had my drawing engraved. Next to the Condor, the Lämmergeier of Switzerland, and the _Falco destructor_ (Daud.), probably Linnæus’ _Falco Harpyia_, are the largest of all _flying_ birds. The region which may be regarded as the common resort of the Condor, begins at the elevation of Mount Etna. It embraces atmospheric strata which are from 10,000 to 19,000 feet above the level of the sea. Humming birds also, which in their summer flights advance as far as 61° north lat. on the western coast of America, and are on the other hand found in the Archipelago of the Tierra del Fuego, were seen by Von Tschudi in Puna at an elevation of 14,600 feet.[JO] There is a pleasure in comparing the largest and the smallest of the feathered inhabitants of the air. The largest among the Condors found in the Cordilleras, near Quito, measure nearly 15 feet across the expanded wings, and the smaller ones 8½ feet. This size, and the visual angle at which the birds are seen vertically above one’s head, afford an idea of the enormous height to which the Condor soars in a clear sky. A visual angle of four minutes, for instance, would give a vertical elevation of 7330 feet. The cavern (Mackay) of Antisana, opposite the mountain of Chussulongo, and where we measured the birds soaring over the chain of the Andes, lies at an elevation of nearly 16,000 feet above the surface of the Pacific; the absolute height which the Condor reached must therefore be 23,273 feet, a height at which the barometer scarcely stands at 12·7 inches; but which, however, does not exceed that of the loftiest summit of the Himalaya. It is a remarkable physiological phenomenon that the same bird, which wheels for hours together through these highly rarefied regions, should be able suddenly, as for instance on the western declivity of the volcano of Pichincha, to descend to the sea-shore, and thus in the course of a few hours traverse, as it were, all climates. At heights of 23,000 feet and upwards the membranous air-sacs of the Condor must undergo a remarkable degree of inflation after being filled in lower regions of the atmosphere.