be not a nebula at all, but a cluster of stars so enormously remote as to be unanalyzable by the most powerful of modern telescopes. In relation to nebulæ, a word may be said on Mr. Lockyer's ingenious "meteoric theory," submitted to the scientific world in 1887. Nebulæ, he asserts, "are composed of spare meteorites, the collisions of which bring about a rise of temperature sufficient to render luminous one of their chief constituents, magnesium." But the spectroscopic coincidences upon which this theory is based are by no means verified, nor has any comprehensible theory of the origin of these meteorites—very complex bodies, according to the samples that have reached our earth—been offered. If, following the indications of recent chemical and physical research, we consider the elements as molecular differentiations of the ether, the nebulæ may present stages in this differentiation in which the molecular states of some of the elements are not identical with those with which we are familiar in the laboratory, in which, indeed, certain of the elements may not yet have been evolved.—The Spectator.
|SKETCH OF WILLIAM EDWARD WEBER.|
WITH the death of Weber, June 23, 1891, passed away, as M. Mascart, of the Central Meteorological Bureau of France, has well said, the last representative of that generation of men of science that cast so much luster on the first half of this century. He was also the last survivor of that group of experimenters in Europe and America whose labors gave the world the electric telegraph; the one among them who first demonstrated that communication by electricity was possible and practicable.
William Edward Weber was born in Wittenberg, Prussia, October 24, 1804. He was the second of three sons of the learned theologian, Michael Weber, Professor of Theology at Wittenberg. The other two sons became doctors, both contributed to science, and both co-operated with the subject of this sketch in some important investigation. Weber studied at the Frankean School and the University of Halle, received his doctor's degree in 1826, became privat-docent at Halle in the next year, and Professor-Extraordinary of Physics there in 1828. In 1831 he was appointed to succeed John Tobias Mayer as Professor of Physics in the University of Göttingen. Ho remained there till 1837, when a political event caused his retirement. On the death of King William IV of England and Hanover, the kingdom of Hanover was separated from England by the operation of the Salic law, and fell to Ernest Augustus, Duke of Cumberland, uncle of King