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Rh $160,000, with a ground-plan of 115 feet by 100. It will be of brick, with cut-stone trimmings, and strictly fire-proof; of three stories, with high basement, making, virtually, four stories. This basement will be largely devoted to the exhibition of fossil footprints. The first story will be devoted to a lecture-room and a mineralogical cabinet; the second to geology, with the fossil vertebrates from the Rocky Mountains; the third to zoology, and the attic to archaeology and ethnology. The funds for the erection and maintenance of this institution were furnished, in 1866, by the late George Peabody, who, by deed of gift dated October 22d of that year, gave $150,000 to Profs. J. D. Dana, O. C. Marsh, B. Silliman, G. J. Brush, and three others, in trust "to found and maintain a Museum of Natural History, especially of the departments of zoology, geology, and mineralogy, in connection with Yale College." The present curators of the several departments of the Museum are Prof. Brush, of the mineralogical, Prof. Marsh, of the geological, and Prof. A. E. Verrill, of the zoological department.

The Movement of Storms.—The American Journal of Science for July contains Part I. of an able paper, by Prof. Loomis, entitled "Results derived from an Examination of the United States Weather Maps for 1872 and 1873," read before the National Academy of Sciences in April last. The weather-maps which furnished the data for his examination exhibit storm-paths for 314 days. These he has carefully tabulated and classified. The course and velocity of the storms for each month are given, showing that the average velocity in forward movement was 26.6 miles per hour, that the greatest average velocity in any month was in February, it being 31 miles per hour; the lowest was in August, when the rate was 17.7 miles an hour. It also appears that their forward movement is greater in winter than in summer. But some atoms move with exceptional velocity. Thus, in May 15, 1873, a storm-centre advanced 1,200 miles in twenty-four hours, while, in other cases, there was no forward movement, and the storm-centre remained stationary for twenty-four hours. The average direction of the storm-paths for two years was 8° north of east; in summer, nearly due east; in winter, more northward; but most northward in fall and spring. In October the direction was 21° north of east. Instances occurred, however, in which storms moved north-northwest; and, on the 6th of April, 1873, a storm in the Mississippi Valley moved in every direction in a little more than twenty-four hours.

Prof. Loomis carefully studied the causes which appear to influence the velocity and direction of storms. Of these, rainfall is important. It is found that the area of rainfall extends farther on the eastern than it does on the western side of a storm-centre; so that the rain-area is a long oval, the longer diameter of which is in or nearly in the direction in which the storm is moving. This is true of most of the storms which traverse the United States. This rain-area extends to an unusual distance on the eastern side of a storm when it is advancing—the average extent being about 500 miles.

By the condensation of vapor eastward of the storm, it, in a measure, makes its own way. Thus the barometer continually falls in advance of it, announcing its approach, but rises as the storm-centre is past. The conditions by which a storm is sustained, and which are present before or in front of it, cease to exist in its wake. Instances occur, however, in which increased velocity and condensation in the western quadrant of a storm set back the storm's centre, and give it, for a time, a retrograde motion. The wind on the western quarter of a storm usually blows with greater velocity by about 22 per cent. than it does on its eastern quadrant, and this is a means by which the forward motion is retarded; and it is found that, when the wind's velocity in the western quadrant is 44 per cent. greater than in the eastern, the storm's forward motion is seven miles an hour less than its average rate of progress.

The atmosphere in the storm circuit moves inward, but also upward, to the central region of the storm, which is supposed to be from one to two miles above the earth's surface. At this elevation atmospheric movements are greatly increased in velocity. Thus, at the summit of Mount Washington, the velocity was 29 miles an