* GROVE, William Robert, Q.C., an eminent electrician, colleague of Dr. Faraday in the Royal Institution, and vice-president of the Royal Society, was born on the 14th July, 1811, at Swansea. He was sent at an early age to Oxford, where he graduated in 1835. His career as a barrister was marked by distinguished success, and in 1852 he was made queen's counsel. But while the highest prospects were thus opened to him in the legal profession, the natural tendency of his mind to scientific pursuits led him to devote every moment of his leisure to experimental investigations, chiefly in electro-chemistry, which have resulted in discoveries of the highest importance to science. In 1839 he invented the nitric acid battery, which is commonly known by his name, and is the most powerful voltaic combination in use. In the same year (1839) Mr. Grove effected the recomposition of water by means of the voltaic current produced by its decomposition. In experimenting on the passage of the electric discharge through the vapour of phosphorus, in 1852, he observed for the first time that the discharge was traversed by a number of dark bands or striæ, a phenomenon not yet understood, but which has lately assumed a deep interest in connection with the brilliant phenomena of Ruhmkorff's coil. In an interesting lecture on this subject which he delivered at the Royal Institution in January, 1859, Mr. Grove hazarded the conjecture that these remarkable stratifications are due to waves or pulsations in the rarefied medium produced by the conflict of opposing secondary currents in the induced wire. But to mention in detail his numerous discoveries would be quite incompatible with the limits of this work. They are chiefly to be found in the Transactions of the Royal Society, the Journal of the Royal Institution, the Philosophical Magazine, and other scientific journals. The only work which Mr. Grove has published in a separate form is an essay on the "Correlation of Physical Forces," the views contained in which were first advanced in a lecture delivered at the London Institution in January, 1842, and subsequently more fully developed in a course of lectures in 1843. This work, of which a third edition was published in 1855, and a French translation by the Abbé Moigno in 1856, contains a masterly elucidation of the modern dynamic theory, which attributes the effects of the chemico-physical forces to molecular motion. The position which the writer endeavours to establish is, that "the various affections of matter which constitute the main objects of experimental physics, namely, heat, light, electricity, magnetism, chemical affinity, and motion, are all correlative, or have a reciprocal dependence; that neither, taken abstractedly, can be said to be the essential cause of the others, but that either may produce or be convertible into any of the others." According to this view the so-called imponderables are mere affections or conditions of ordinary matter; there is no luminous ether, no material caloric, no electrical fluid. The motion or vibration of the particles of ordinary matter produces under certain conditions light, heat, and electricity, and electricity produces magnetism and chemical affinity. Mr. Grove therefore rejects Dr. Black's theory of latent heat—an expression which he considers to be equivalent to latent matter or invisible light. The non-conduction of electricity in vacuo—a fact established by Mr. Gassiot, and first decisively announced by Mr. Grove in his lecture at the Royal Institution in January, 1859—affords a remarkable confirmation of these views, as showing that the presence of matter is essential to the transmission of electricity. The same views have long been held by Faraday; they have already received the sanction of the highest names in science, and their able advocacy by Mr. Grove promises to give a powerful impulse to their dissemination.—G. BL.
GRUBER, Johann Gottfried, a distinguished German litterateur, was born at Naumburg, 29th November, 1774, and studied at Leipsic, where he began his literary career by the publication of his essay on the destiny of Man, and his "Versuchseine pragmatischen Anthropologie." In 1805 he settled at Jena as a lecturer, and as one of the editors of the Allgemeine Literatur Zeitung. Here he published conjointly with Danz his "Charakteristik Herder's." In 1811 he obtained a chair in the university of Wittenberg, whence in 1815 he was translated, together with the university, to Halle. He now entered upon the most comprehensive and most important work of his life—the celebrated Cyclopædia of Science and Arts; which was originated by Professor Ersch and himself in 1818, and has not yet been completed. This is, perhaps, the grandest literary undertaking of its kind, and will secure its editors a lasting fame. At the same time Gruber again edited the Allgemeine Literatur Zeitung, one of the most influential organs of German literature. Notwithstanding the arduous tasks thus imposed upon him, so untiring was his industry, that he still found leisure for a number of miscellaneous works, among which we note the biographies of Wieland, 2 vols.; of Herm. Aug. Niemeyer (begun by Jacobs) and of Lafontaine; a dictionary of classical mythology, 3 vols.; and a "History of the Human Race," 2 vols. Gruber died at Halle, August 7, 1851.—K. E.
GRUENEWALD, Matthæus, a good old German painter of Asschaffenburg in Bavaria, of whom, however, nothing more is known than is given in the vague account of Sandrart. He is said to have been the pupil of Albert Dürer; but as his time does not accord with such a possibility, he was most probably the rival of Albert. Sandrart fixes his death at about 1510, and says he was inferior to none of his contemporaries. Fiorillo assumes him to have been a generation younger. Though, by no means equal to Albert Dürer, Grünewald was a good painter for his time, and an important work by him, an altarpiece, was exhibited by the prince consort at Manchester in 1857. He was established and died at Frankfort; he lived also some time at Mayence. Sandrart speaks very highly of his drawings, and calls Grünewald the German Correggio, an unintelligible compliment, unless referring to his chalk drawings only. There are several of his pictures in the gallery at Munich; but they have as little of the graceful in them as is well possible. His heads are correct, but hard and minute in their details; his colouring is positive. He is said to have cut in wood, but this is doubtful. Hans Grünewald, a contemporary and probably relative, did engrave in wood; of this painter also, we are in almost total ignorance.—R. N. W.
* GRUNDTVIG, Nicolai Frederik Severin, one of the most colossal intellects of Denmark, antiquarian, poet, and preacher, was born at the parsonage of Udby in South Zealand, 8th September, 1783. In his ninth year he was sent from the pleasant idyllian country of his birth, to the wild and dreary moorlands of Jutland, to be educated for the church. Here he spent six years, after which he went to the Latin school at Aarhuus. In 1803 he passed his theological examination, and attended the lectures of his cousin Steffens on natural philosophy and the poetry of Göthe. Soon after becoming acquainted with Saxo and Snorre, he began a profound study of the literature and language of Iceland. From 1805 to 1808 he was private tutor in Langeland, where he first read Shakspeare, Göthe, Schiller, Fichte, Schelling, &c. This was the spring-time of his life; and he published many articles in Rahbek's Minerva on the songs of the Edda, and the principles of the Odinic mythology; but notwithstanding their power and originality, they attracted but little notice. The same year he came to the capital, taught history in a school, and made the acquaintance of the first men of the time, amongst whom were Sibbern and the brothers Oersted. He also published his "Nordens Mythologie, eller udsigt over Eddalaren," the first work in which the Scandinavian mythology is placed in a poetic and philosophical light; and the following year, "Optrin af Kjæmpelivets undergang i Nord." In the meantime he became the subject of deep religious conviction; and after preaching a probationary sermon, which provoked the wrath of the rationalistic clergy, he retired to his father's house, and became his assistant. Here he laboured industriously; and the next year produced his "Kort Begreb af Werdens Krönike." After the death of his father in 1813, he returned to Copenhagen, where he lived a hermit's life amongst his books and the few friends who remained to him. For eight years, pursued by the wrath of his brethren in the ministry whom his first sermon had provoked, he sought in vain for a clerical appointment, and could scarcely obtain even a pulpit in Copenhagen in which to preach occasionally. But his literary industry was unwearied, and he brought out "En liden Bibel-Krönike;" "Roeskilda Rüm," and "Roeskilda Saga;" "Kvœdlinger eller Smaaquad;" a collection of his smaller poems, "Bibelsk Prædikener" (Scripture Sermons), and various other works, besides editing the periodical Dannevirke. From the year 1815, Grundtvig had applied himself to Anglo-Saxon literature—for some time in connection with Rask—and now, in 1820, appeared his free translation of Biörvulf's Drapa, and in 1822 he completed his largest and most laborious work, his translations from Saxo and Snorre. In 1818 he married, and in 1820 was appointed pastor of Præstö, and the following
