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Rh For twenty years lie performed faithfully and impartially the duties of his office in one of the classes of the Institute. His annual reports, his historical eloges, which have been published, and his exposition of the progress of science are eminently distinguished by profound erudition, literary skill, and, above all, by generous appreciation of the works cf others. His literary and scientific labours were very numerous, and, in respect of excellence, of the highest order. His History of Astronomy, published at intervals, and forming when complete six quarto volumes, is a work of prodigious research. It puts the modern astronomer in possession of all that had been done, and of the methods employed by those who lived before him. His Methodes Analytiques pour la Determination d un Arc du Meridien, his numerous memoirs in the additions to the Connaissances des Temps, and his Astronomic Theorique et Pratique exhibit the finest applications of modern analysis to astronomy and geography. It is a remarkable fact that Delambre did not apply him self to astronomical observations until he had reached the comparatively late age of thirty-five. He was appointed a member of the Royal Council of Public Instruction in 1814; but he lost the place in 1815. He was in Paris when it was taken by the allied armies ; and, in a letter written at tha,t time to a friend and pupil, he says that on the day of the siege, in the hearing of the cannon ade, he laboured with tranquillity in his study from eight in the morning till midnight. He had a happier fate than Archimedes in a like position, for he was not molested by the victors, and no one was billeted on him, probably from respect to his high reputation. At the creation of the Legion of Honour in 1802 Delambre was made a member of that order. He was appointed chevalier of St Michael in 1817, an officer in the Legion of Honour in 1821 ; but a long time before, he had been created an hereditary chevalier, with an endowment, which was decreed as a national reward. The life of continued and hard study which Delamt&amp;gt;re led at last affected his health. The disease by which he was cut off became apparent in the month of July 1822. His total loss of strength, with frequent and long continued fainting-fits, gave warning of a fatal result, which occurred on the 19th August 1822. The following is a list of his works which appeared separately : Tables de Jupiter et de Saturn (1789) ; Tables du Soleil, de Jupiter, de Saturn, d Uranus, ct dcs Satellites de Jupiter, pour scrvir d la 3mc edition I Astronomic dc Lalandc (1792) ; Mithodcs Analytiques pour la Determination d un Arc du Meridien (1799) ; Tables Trigonometriques Decimates, par Borda, revues, augmentees, et publites par M. Delambre, (1801) ; Tables du Soleil, publiees par le Bureau dcs Longitudes (1806) ; Base du Systeme Metrique De cimal, &c. (3 vols. in 4to, 1806-1810) ; Rapport Historique sur les Progres des Sciences Mathematiques depuis 1789, &c. (1810) ; Abrcge d Astronomic, ou Lecons JtZlemcntaires d Astronomic Theorique ct Pratique, in 8vo ; Astronomic Theorique ct Pratique (3 vols. in 4to, 1814); Tables Ediptiqucs dcs Satellites de Jupiter (1817) ; Histoire de V Astronomic Ancienne (2 vols. in 4to, 1817) ; Histoire dc I Astronomic du Moyen Age (1819, 1 vol. in 4to) ; His toire dc V Astronomic Moderne (1821, 2 vols. in 4to) ; Histoire de T Astronomic au Dixhuitiemc Siecle (1 vol. 4to, 1827). In addition to these, he furnished a very considerable number of memoirs (about 28) on various points of astronomy to the Connaissances de Temps, beginning with the year 1788. He also contributed to the Memoirs of the Academies of Stockholm, St Petersburg, Berlin, and Turin, and to those of the first class of the French Institute ; and he composed eloges on many of his contemporaries at their death.

 DE LA RIVE, AUGUSTE (1801-1873), a Swiss physicist, distinguished chiefly for his researches on the subject of electricity, was born at Geneva on the 9th October 1801. He belonged to a good family closely connected with that of the Count Cavour, and he inherited his taste for natural science from his father, an eminent physician and chemist. After an unusually brilliant career as a student, he was ap pointed at the early nge of twenty-two to the chair of natural philosophy in the Academy of Geneva. For some years after his appointment he devoted himself specially to the investigation of the specific heat of gases, and to obser vations for determining the temperature of the earth s crust. In the latter inquiry he availed himself of an artesian well that had been bored to a depth of 700 feet, and his ebser- vations were adopted by Poisson as the basis of his calcula tions. The comparatively new subject of electricity, how ever, received much of his attention from the first, and it gradually became the chief object of his scientific work. His name is associated with original discoveries in connec tion with magnetism, electro-dynamics, the connection of magnetism with electricity, the properties of the. voltaic arc, and the passage of electricity through extremely rarefied media. His researches ou the last-mentioned subject led him to form a new theory of the aurora borealis, which, though not free from difficulties, is on the whole the most probable explanation of a very obscure phenomenon. The most valuable practical result of his scientific discoveries was the process of electro-gilding carried out by Messrs Elkington & Ruolz from a memoir which he communicated to the Academic des Sciences. By making it known in this way he voluntarily renounced all the profits of his discovery. Between 1853 and 1858 De la Rive published a complete treatise en electricity in three octavo volumes, which was regarded as a work of high authority, and was at once translated into English, German, and Italian. Its author s scientific reputation received the usual recognition in his election to the membership of most of the learned societies of Europe. In 1842 he received the grand prize of 3000 francs from the Academic des Sciences for his dis covery of the electro-gilding process ; and in 1864 he received the highest honour open to the scientific men of Europe in his nomination as one of the eight foreign associates of the Academy. De la Rive s birth and fortune gave him considerable social and political influence. He was distinguished for his hospitality to literary and scientific men, and for his interest in the welfare and independence of his native country. In 1860, when the annexation of Savoy and Nice had led the Genevese to fear French aggression, De la Rive was sent by his fellow-citizens on a special embassy to England, and succeeded in securing a declaration from the English Government, which was communicated privately to that of France, that any attack upon Geneva would be regarded as a casus belli. On the occasion of this visit the university of Oxford confejrred upon De la Rive the honorary degree of D.C.L. When on his way to pass the winter at Cannes he died suddenly at Marseilles, on the 28th November 1873.

 DELAROCHE, HIPPOLYTE, commonly known as PAUL (1797-1856), one of the most accomplished painters of the eclectic modern school, was born in Paris, 17th July 1797. He is always spoken of as one of the most fortunate and successful of men, as well as one of the ablest, since he never appeared to encounter any obstacles or to feel any difficulties. The father of Delaroche was an expert who had made & fortune, to some extent, by negotiating and cataloguing, buying and selling. He was proud of his son s talent, and able to forward his artistic education. The master selected was Gros, then painting life-size histories, and surrounded by many pupils. In this atelier Delaroche met Bonington (an English youth of whose work we see little, but who has had a very considerable influence in France), Roqueplan, Bellange, Eugene Lami, and others. In no haste to make an appearance in the Salon, his first exhibited picture was a large one, Josabeth saving Joas, 1822. This picture led to his acquaintance with Gericault and Delacroix, with whom he remained on the most friendly terms, the three VII. 6

