A. MATHEMATICS AND ASTRONOMY. 15 



our system. As observatories have their regular work, which 

 will not permit them to search for these bodies, it is expected 

 that professors and private parties in possession of good tele- 

 scopic instruments will enter the field in competition for the 

 prize. 15 A, July 29, 148. 



NEW ASTEROID. 



A new planet was discovered on the night of September 13 

 last, at Marseilles, by M. Borelli, and named by him Lomia. 

 This constitutes the one hundred and seventeenth in the se- 

 ries of asteroids found between Mars and Jupiter. 



NEW ASTEROID. 



Another was discovered on the 11th of September by Dr. 

 Peters, of Hamilton College, New York, the same body hav- 

 ing been observed six days afterward by Luther, at Bilk. 

 This will be the one hundred and sixteenth of the series. 



THE NATURE OF COMETS. 



M. Faye, of the French Academy of Sciences, has lately 

 read to that society two elaborate papers on the history and 

 present state of the theory of comets. He commences with 

 some critical remarks on- a passage in the address of Sir Wil- 

 liam Thompson before the British Association last summer, 

 in which the Tatter spoke of the comet's tail as having been 

 one of the insoluble mysteries of astronomy. M. Faye con- 

 cludes from this view that the Continental astronomers have 

 not spread the knowledge of their labors in England, and 

 that the English have forgotten Newton's " Principia." Ac- 

 cording to Faye, it is an established principle that the tails 

 of comets, whether simple or compound, are due to a repul- 

 sive force exerted by the sun. The principal characteristics 

 of this force have been clearly determined. Far from contra- 

 dicting the received laws of mechanics, as Herschel seemed 

 to suppose, it is precisely by means of these laws that the 

 most complicated phenomena of the tails have been account- 

 ed for on the hypothesis of a repulsive force. All that is 

 wanting is to learn the exact nature of this force, and, if pos- 

 sible, exhibit its action experimentally. This is what the au- 

 thor has attempted. He lays down a law, or, rather, until it 

 is proved experimentally, a hypothesis, which he calls the 



