My expedition into northern Asia (to the Ural, the Altai, and the shores of the Caspian Sea) in the year 1829, with Ehrenberg and Gustavus Rose, at the command of the Emperor of Russia, took place between the second and third editions of my work. This expedition has essentially contributed to the enlargement of my views in all that concerns the formation of the earth’s surface, the direction of mountain-chains, the connexion of the Steppes and Deserts, and the geographical distribution of plants according to ascertained influences of temperature. The ignorance which has so long existed respecting the two great snow-covered mountain-chains, the Thian-schan and the Kuen-lün, situated between the Altai and Himalaya, has (owing to the injudicious neglect of Chinese sources of information) obscured the geography of Central Asia, and propagated fancies instead of facts, in works of extensive circulation. Within the last few months the hypsometric comparisons of the culminating points of both continents have unexpectedly received important and corrective illustration, of which I am the first to avail myself in the following pages. The measurement (now divested of former errors) of the altitude of the two mountains, Sorata and Illimani, in the eastern chain of the Andes of Bolivia, has not yet, with certainty, restored the Chimborazo to its ancient pre-eminence among the snowy mountains of the new world. In the Himalaya the recent barometric measurement of the Kinchinjinga (26,438 Parisian, or 28,178 English feet) places it next in height to the Dhawalagiri, which has also been trigonometrically measured with greater accuracy. To preserve uniformity with the two former editions of the _Views of Nature_, the calculations of temperature, unless where the contrary is stated, are given according to the eighty degrees thermometer of Reamur. The lineal measurement is the old French, in which the _toise_ is equivalent to six Parisian feet. The miles are geographical, fifteen to a degree of the equator. The longitudes are calculated from the first meridian of the Parisian Observatory. _Berlin, March, 1849._ CONTENTS Page PUBLISHER’S PREFACE v AUTHOR’S PREFACE, TO THE FIRST EDITION ix AUTHOR’S PREFACE, TO THE SECOND AND THIRD EDITIONS xi SUMMARY OF CONTENTS xvii STEPPES AND DESERTS 1 Illustrations and Additions 22 CATARACTS OF THE ORINOCO 153 Illustrations and Additions 174