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 LEVERRIER LE VERT 379 at the same conclusion about the same time, but who was less fortunate than his French rival in making it known to the world. (See ADAMS, JOHN COUCH.) In 1848 Leverrier made some ineffectual efforts to distinguish himself as a democratic leader, but it was not till 1849 that he was elected from La Manche to the legislative assembly. He modified his liberal views, took his place among the coun- ter-revolutionary members, and occupied him- self principally with questions of public in- struction and with laws relative to scientific discoveries. He was in consequence appointed to prepare several important reports relative to the construction of electric telegraphs, the organization of the polytechnic school, and re- cruiting for the corps of engineers. When a decided division into parties took place in the assembly, Leverrier joined the imperialists. After the coup d'etat of Dec. 2, 1851, he was appointed senator, and some time after in- spector general of public instruction. He exerted a decided influence on public instruc- tion in France, particularly with regard to the polytechnic school. In 1849-'50 he read to the academy of sciences an account of new investigations into the movements of the planets, and in 1853 presented to it tables of the sun's rotation, with the complete system of the small planets situated between Mars and Jupiter. In 1853, on the death of Arago, Le- verrier succeeded to the title and authority of director of the observatory. During his tenure of this office he was much occupied in urging upon government a reform of the old method of observations, which caused much dispute between himself and his colleagues. In Sep- tember, 1859, he communicated to the academy of sciences a movement of the perihelion of Mercury, which could be accounted for only by the supposition of another planet, or per- haps a series of small bodies, moving between it and the sun. This communication called forth Dr. Lescarbault's revelation of a dis- covery which he asserted that he had made at Orgeres as early as March 25, 1859, of a new planet, which received the name of Vulcan, and which was announced through Leverrier to the academy of sciences in the beginning of 1860. But subsequent researches have failed to establish the existence of such a planet. On June 3, 1861, Leverrier communicated to the academy of sciences a letter on the constitution of the planetary system, and on the theory and tables of Mars. The following are the results presented in this paper: 1. There is between Mars and the sun a ring of asteroids whose united mass is comparable to that of Mercury. 2. At the distance of the earth from the sun there is a second ring of asteroids, whose mass is nearly equal to the 10th part of that of the earth. 3. The united masses of the asteroids between Mars and Jupiter is nearly equal to the third part of the mass of the earth. 4. The masses of the last two groups are complementary to each other. Ten times the mass of the group at the earth's distance added to three times the united mass of the zone between Mars and Jupiter is nearly equal to twice the mass of the earth. In 1870 Le- verrier found it desirable to withdraw from the office of director of the observatory, differ- ences having arisen between himself and other eminent astronomers. Delaunay succeeded to the post, which he retained till his death by drowning, Aug. 5, 1872, soon after which Leverrier was reappointed. Shortly before this he had published an important memoir on the theories of the four exterior planets. This is noteworthy as in part withdrawing the ideas promulgated in the paper of 1861, above mentioned. " It has been proved," says Leverrier, "that the matter of which no ac- count had hitherto been taken in the theory of Mars ought to have been added to the earth itself, the estimate of the mass of our planet being one eighth too small." This of course relates to the recognition of the fact that the sun's distance is not so great as has been sup- posed. For the diminution of the sun's dis- tance and of all the distances within the solar system (save the moon's alone), in the propor- tion of about 143 to 149, corresponds to the reduction of the relative masses of the sun and all the planets as compared with the earth in the proportion of (143) 3 to (149) 3, or roughly as 137 to 155 ; which is the same as saying that the earth's mass is increased relatively in the proportion of 155 to 137, or by about an eighth piart. "With regard to Mercury," Leverrier proceeds, "this confirmation is not yet com- plete. Several astronomers have placed on record the passage over the sun's disk of va- rious small bodies, which could be nothing else but very small planets, but it has not been pos- sible to determine the orbit of any one of them. Whether we have to deal with the action of a certain number of small masses, or with that of matter distributed in the neighborhood of the sun, the theory of Mercury has been de- termined with considerable care, and the tran- sits of the planet over the sun's disk furnish us with observations too precise to admit of any doubt of the accuracy of our results, espe- cially as they have been obtained in the same manner as for Mars ; and for this latter plan- et the confirmation which the theory has re- ceived leaves nothing more to be desired." He then recommends corresponding researches into the theory of the four large planets, as they would furnish us with data concerning any matter still unknown to us that may be situated in those regions. It is probable that the greater part of Leverrier's time will here- after be given to this important subject. LE VERT, Octavia Walton, an American au- thoress, born near Augusta, Ga., about 1810. She is a granddaughter of George Walton, one of the signers of the Declaration of Indepen- dence. Her father removed to Pensacola in 1821, having been appointed territorial secre- tary for Florida, under Gen. Jackson as gov-