"LEVERRIER, URBAN-JEAN-JOSEPH, was born at St. Lo, in the department of La Manche, in France, on March 11, 1811. He was educated successively at the college of St. Lo, at Caen, and at Paris, and was admitted to the Polytechnic School in 1831. His early inclination seems to have been towards chemistry, as he published in 1837 two essays on the combination of phosphorus with hydrogen and with oxygen, and contributed some chemical papers to the tionnaire de la Conversation.' He began next to distinguish himself as an astronomer, and his ' Tables de Mcrcure,' and some essays ' eur les inegalites seculaires,' which appeared in the Connaissance des Temps,' procured his admission to the Acaddmie des Sciences in January 1846, where he succeeded Jean-Dominique Cassini. In this year ho made his grand discovery of the new planet Neptune. Ho had begun in 1845, at the instance of Arago, to investigate the orbit of Uranus, and from certain perturbations, which he reduced to calculation, proved the necessary existence of a new planet to account for them, and indicated the place where it would probably bo found. After a few previous papers to the Institute on the results of his investigations on November 10, 1845, June 1, and August 1, 1S46, on the 5th of October 1846, in the 'Connaissance des Tempe' for 1849, his theory was fully developed. Suspicions of the existence of such a cause for the disturbance had been previously expressed by Messrs. Bouvard and Hessen. We have already mentioned that in England Mr. Adame had been pursuing a similar course, sod had arrived at tho same results somewhat earlier, but had printed nothing. [ADAMS.] Alexander von Humboldt, in a note to his Cosmos ' (n. 690, vol. iii.), thus notices the dates of the steps in the discovery of Adams and Leverrier—Leverrier'a we have given : "Adams, without printing any thing, laid the first results which he obtained for the perturbing planet before Professor Challis in September 1845, and the same, with some modification, in the following month, October 1845, before the astro nomer-royal, still without publishing anything. The astronomerroyal
received from Adams his final results, with some fresh corrections relating to a diminution of the distance, in the beginning of September 1846. The young Cambridge geometrician has expressed himself with noble modesty and self-denial on the subject of this chronological suc cession of labours, which were all directed to the same great object.
mention these earlier dates merely to show that my results were arrived ot independently and previously to the publication of M. Leverrier, and not with the intention of interfering with his just claims to the honour of the discovery ; for there ie no doubt that his researches veers first published to the world and led to the actual discovery of the planet by Dr. Galie : so that the facts stated above cannot detract in the slightest degree from the credit due to M. Leverrier.' '' On the verification of Leverrier's discovery honours of all kinds were showered upon him ; be was created Professor of the Faculty of Sciences, member of the Bureau de Lou gitude, director of the observatory, an officer of the Legion of Honour, and was chosen member of the Legislative Assembly by the depart ment of La Manche; the Duke of Tuscany presented him with the works of Galileo, and the Royal Society of England bestowed on him the gold Copley medal and elected him a member. On the revolu tion of December 2, 1851, he took part with the present Emperor of the French, was shortly after named a senator, and on the death of Arago succeeded him as astronomer to the Bureau de Longitude.