Scientific Intelligence. — Astrcmomy. 181 



astronomers, M. Damoiseau, member of the Academic des 

 Sciences. All that has been said in Germany respecting this 

 comet, is founded on the results obtained at Paris. Now, these 

 results are so far from being terrifying, that they do not even 

 leave the smallest possibility of an accident. The comet of 1832, 

 in its shortest distance from the earth, will remain more than 

 sixteen millions of leagues from it. It might come a thousand 

 times nearer before any danger could be apprehended. In 

 1770, a comet came so near as 750,000 leagues (about nine 

 times nearer than the moon). Lalande estimates the distance at 

 which a comet might produce sensible effects on the earth, at 

 13,000 leagues. Whence, then, comes the error of the journalists, 

 of whom the author of the letter speaks ? Without doubt, solely 

 from the circumstance, that the comet in question will pass very 

 near the earth's orbit (at 4| diameters, from 13000 to 14000 

 leagues) ; so that, in fact, were the earth to be at the time in the 

 part of its orbit nearest the comet, some alarming disturbances 

 might ensue. It is unnecessary to say that so gross a misappre- 

 hension as that which we have just pointed out, was not com- 

 mitted by any astronomer. The only respectable publication in 

 Germany on the subject is a letter of M. Olbers, in which that 

 astronomer gives an account of the results obtained by M. Da- 

 moiseau ; and it is without doubt, because ignorant persons have 

 seen in this letter that a comet will approach very near the 

 earth's orbit in 1832, that they have persuaded themselves of its 

 collision with the earth. M. G * * ♦'s letter contains an assertion 

 with reference to Lalande, which we think it our duty to refute. 

 That astronomer was but the very innocent cause of the general 

 terror which pervaded the public mind in 1773. The following 

 is the real case : — Newton, in speaking of the consequences that 

 might result from a comet's coming in contact with the earth, 

 had said that Providence had so arranged as to render such a 

 collision impossible. Lalande thought differently. No orbit, it 

 13 true, was known that might interfere with that of the earth ; 

 but the orbits might be sensibly altered by the planetary attrac- 

 tions. Besides, the orbits of all the comets were very far from 

 being known. Was it not rash to pronounce it certain, that 

 none of the orbits hitherto not calculated, could come into con- 

 tact with that of the earth, and that, of those known, none could 



