ASTRONOMY AND METEOROLOGY. 345 



however minute the excess, they would pass from the system. Le- 

 verrier has shown that the action of Jupiter upon Lexell's comet had 

 changed its orbit into the hyperbolic form. So, with this excess 

 of motion, they would pass into another system, and thus pass from 

 system to system, until they would pass so near some planet as to have 

 their orbit reduced to the parabola or ellipse. 



One remark with regard to the direction from which they come. 

 Out of 90 direct comets, there were 57 which came from the south, 

 and 33 from the north. The retrograde comets were nearly in the 

 same proportion. Out of 94, there were 55 from the south, and 39 

 from the north. This difference, however, might simply be the acci- 

 dent of observation. 



AMERICAN NAUTICAL ALMANAC. 



CONGRESS at its last session passed an act authorizing the preparation 

 of a Nautical Almanac, and appropriating $6,000 to commence the 

 work. Lieut. Charles H. Davis was appointed, by the Secretary 

 of the Navy, to take charge of it, and he entered upon his duties as 

 soon as possible. The office is at present situated in Cambridge, 

 Mass., but it will probably soon be removed to Washington. We 

 learn from the report of the Secretary of the Navy, that Lieut. Davis 

 asks for an appropriation of $13,000 to defray the expenses of the 

 work during the ensuing year ; this sum will enable him to enlarge 

 considerably the present corps of computers. Lieut. D. has, we are 

 informed, secured the valuable services of Prof. Peirce, of Harvard 

 University, whose acknowledged ability as a man of science, and world- 

 wide reputation as a mathematician, cannot fail to inspire increased con- 

 fidence in the correctness of the work. Two such men as Lieut. Davis 

 and Prof. Peirce cannot fail to produce a valuable volume. The theory 

 of Mars is now in progress. In the first number, which, on account of 

 the immense amount of labor to be performed, cannot be published 

 till about 1852, the ephemerides of some of the planets will be based 

 upon new theories, which will make them much more reliable than any 

 heretofore published. Editors. 



ASTRONOMICAL JOURNAL. 



THE American Association, at its meeting at Cambridge, voted that 

 a journal is needed in this country, to be devoted especially to recording 

 the results obtained by our astronomers, and they referred the subject 

 to a committee, who drew up a prospectus. They say, " An Astro- 

 nomical Journal for the publication of original researches has long been 

 needed in the United States, and the want is growing more urgent every 

 day. American astronomy demands an organ, in which important in- 

 vestigations and observations may be published without delay, and which 

 may serve especially as a magazine for astronomical researches made in 

 this country, as a vehicle of information concerning the labors of indi- 

 viduals, and as an exponent of the general progress of science." They 



