METEORS OF AUGUST AND NOVEMBER. 105 



velocities of the meteors. The degree of deflection of single shooting stars 

 from the theoretic convergent point, affords a classification of these meteors 

 into sporadic and convergent, the former having a greater normal velocity 

 than the latter, and hence, the effect of the other component of their relative 

 velocity and direction being less manifest. This difference of velocities, natu- 

 rally suggests a further classification of the orbits of these bodies, according 

 to the cosmical theory, into very inferior asteroids, visible near their aphelion, 

 and having small true velocities, and therefore conforming closely with the 

 principal component of their relative directions, namely, the observer's tangential 

 motion extended in an opposite direction. The sporadic meteors in contra-dis- 

 tinction from the others, may then be regarded as asteroids, superior to the con- 

 vergent class, and, in many instances, superior to the earth. Then their true 

 velocities being great, this component causes so great a deflection of their 

 relative paths, that their relation to the other component is overlooked. 



2. It is possible that the above classification may apply to the meteors of the 

 12th and 13th November, seen since 1833; since the supposed deflection of 

 the convergent point of only 8° or less, may be ascribed to the errors of obser- 

 vation. 



3. The convergent point of the great shower of 1833, which exhibited a simi- 

 lar deflection of about 8°, was much better ascertained, since telescopes were di- 

 rected towards it,*^ and its height was measured with a quadrant. ^^ This doubt- 

 less presents an exception to the last remark, in which case we must regard it as 

 an extraordinary group, or cluster, or flock of these bodies, having a common, 

 small normal velocity, and according to Twining's computations, a great relative 

 velocity, nearly the same as that of the observer taken with an opposite sign. 

 Such a cluster must then have had the other component or true velocity of the 

 group very small, and hence its perihelion must have been near the sun. In 

 fact, Prof. Olmsted's convergent point, and Twining's relative velocity, taken as 

 data, would give an orbit coming nearly or quite in contact with the sun, and 

 presenting the singular circumstance of the ballistic curve, so called with 

 respect to the sun, in the same manner, as projectiles from gunpowder, or 

 other forces on the surface of the earth. 



4. The groups composing the displays on the same anniversary, in 1799, 



«^ Sill. XXV., p. 374. "8 Idem, xxvi., p. 331. 



vm. — 2 B 



