including the discovery of the long-sought northwestern passage, and of its inutility. The exploration of the antarctic circle as far as the 73° of south latitude, and the remarkable discovery that the ice-bound regions, both of the Arctic and Antarctic, were, at a former period of the world's history, covered with a luxuriant vegetation, and that plants and animals then existed there in great abundance, which are found now only in the tropics, or in the more southern parts of the temperate zone.
And finally our own explorations of the great Western region, between the Mississippi and the Pacific, by Fremont, Emory, Simpson, Marcy, Stansbury, Sitgreaves, Gunnison, Beckwith, Whipple, Williamson, Parke, Warren, Ives, Reynolds, Macomb, Mullen, Wheeler, and other gallant, efficient, and distinguished military officers conducting reconnoissances or expeditions across its plains, deserts, and mountains, accompanied in these expeditions by scientific civilians, to whose labors we are indebted for our knowledge of its geology, agricultural resources, and natural history. Among strictly scientific works by civilians I should also enumerate Whitney's survey of California, followed by King and Gardner's belt of geological and topographical survey across the North American Cordilleras, Hayden and Gardner's survey in the Rocky Mountains, and Powell and Thompson's of the great canons of the Colorado, through whose united labors so much of the geography of this vast region has become known; its great mountain-ranges, extraordinary canons, wonderful geysers, deeply interesting ruins of a prehistoric and semi-civilized people of whom we know but little; its lakes, rivers, majestic cataracts, broad areas of cultivable land, already largely and to be still more extensively settled, and finally the millions it has yielded in gold and silver; a region so vast beyond the one hundredth meridian, that it will be twenty years before we obtain proper maps of it, unless the Government is more liberal in providing for its exploration and survey than it has hitherto been.
To these geographical labors and explorations within this period in various parts of the globe must also be added extensive researches of a geographical character, such as deep-sea dredgings, for the investigation of the temperature of the ocean, the movements of submerged currents, the plant and animal life existing at great depths, and the configuration of the bottom of the seas. The observation and study of oceanic currents and their cause. The distribution of heat north and south of the equator by the instrumentality of these currents, and its effects upon climate, as well as the effect of the currents from polar regions in modifying the heat of the equator. The meteorological observations in respect to the course of the winds; and the investigations of the laws and of the cause of hurricanes, cyclones, and other aerial disturbances. The magnetic observations in elucidation of the difficult subject of terrestrial magnetism. The numerous measure-
