On the Meteors of 13th November, 1833. 347 



First. — If the meteors were generated under the control of ter- 

 restrial influences — whether atmospheric, electrical, magnetic, or even 

 unknown and merely imaginable — it would seem to be a necessary 

 result that the bodies so generated should conform, in arrangement 

 or motion, to geodesic lines. For example, had the meteors been 

 formed in the upper regions of the atmosphere, and drawn to the 

 earth by gravity, the line of descent ought to have exhibited a change, 

 at different points of observation, corresponding with the change in 

 the place of the zenith : — no such change, however, was observed. 

 We are aware that Prof. Olmsted, in his third proposition (p. 147) 

 has assigned the force of gravity, as "an adequate cause" of the me- 

 teoric motions ; but, besides the total independence of the vertical 

 which those motions exhibited, we think it has been shown that the 

 amount of motion was twice as great, at least, as that which terres- 

 trial gravity is adequate to create. Again, had the meteors been 

 generated, or set in motion, by the cause, whatever it be, of the 

 north-lights, or the auroral arch, or of terrestrial magnetism, we should 

 certainly look for a regular coincidence with the magnetic dip and 

 variation : — but the reverse of such a coincidence do we find.* And 

 in like manner the supposition of any terrestrial origin seems to be 

 cut off and made untenable by the same circumstances, in the ob- 

 served motions of the meteors, by which a similar supposition is 

 made untenable in the case of gravity and magnetism. It must, 

 however, be admitted that the change of declination, in a fixed ratio 

 to the change of the spectator's latitude, which there is reason to be- 

 lieve existed, may chance to turn the point of this argument against 

 us ; unless that change shall appear to have been a result of the po- 

 sition of the earth's axis relatively to the plane of the meteors' prop- 

 er motion — in case such motion existed. 



But when we consider that the meteors were actually seen by 

 many individuals to manifest an independence of the earth's rotation, 

 for two hours and a half — if we compute from the earliest observa- 

 tion in the east, and the latest in the west — and for still an hour more, 

 if we compute from Capt. Parker's observation in the Gulf of Mex- 



* It may be observed, in passing, tbat a scientific gentleman of our acquaintance 

 observed, both during the meteoric shower, and through the day succeeding, a mag- 

 netic needle which was very delicately suspended by a film of silk, without detecting 

 any change ofvaiiationor of dip, or any of those agitations which the needle is subject 

 to, during the prevalence of auroral lights. This observation was made upon the 

 banks of the Hudson river, fifty miles above New York. 



Vol. XXVI.— No. 2. 45 



