19 



November," had been referred, reported in favour of its publi- 

 cation in the Transactions; which was thereupon ordered. 



The paper contains — 1st, Tabular statementsoft.be relative veloci- 

 ties derived from corresponding observations of the same meteor at 

 different stations, chiefly from Quetelet's Catalogue. 2d. A cata- 

 logue of remarkable appearances of shooting stars, also from Quete- 

 let, with additions. 3d. Bessel's position of the earth, in the ecliptic 

 at the date of the principal November showers. 4th. The conver- 

 gent points hitherto observed for the relative paths of the meteors of 

 August, and — 5th. Of those of November. The term periodical is 

 restricted to the meteors, which, at a particular season of the year, 

 tend towards the convergent point for that season. Sporadic is ap- 

 plied to the unconformable meteors seen on the same occasions. Ex- 

 traordinary showers of the second table are placed in the former 

 class, and are considered as differing from periodical meteors only 

 in numbers. The convergent point, as far as noticed for the periodi- 

 cal meteors, is not far from the antipode of the earth's tangential 

 direction. The average relative velocities in table first, with the 

 known convergent points, for August and November, and other 

 parts of the year, as far as observed, afford on the cosmical theory, 

 the most plausible estimate of the elliptic elements of the orbit of 

 periodical meteors. The well-known formulae for computing these 

 elements are stated; and the differential formulae are investigated 

 for computing the probable errors of such elements, arising from 

 errors of the relative velocities and directions derived from the fore- 

 going tables. The most plausible elements of the periodical me- 

 teors, are thus found to have their perihelia inferior to that of Mer- 

 cury, and hence are only seen by us when near their aphelia ; 

 the orbits being necessarily very eccentric, or flattened, and their 

 inclinations very great. Since many millions of these bodies are 

 annually encountered by the earth, including cniefly those which 

 move in orbits having small parameters, analogy leads to the infer- 

 ence, that the planetary spaces inferior to Venus, abound in these bo- 

 dies, of which only a small proportion ever reach the earth's mean 

 distance, or become visible to us. This suggestion of a far greater 

 aggregation of these bodies near the sun, is supported by the analogy 

 of the resisting medium encountered by Encke's comet, which is only 

 sensible at a distance from the sun below that of Venus. Bessel's ob- 

 jections to the theory of the resisting medium, that it is indicated by 

 no other phenomenon in nature, may be in some degree obviated by 

 this analogy; since a very thin, light body, might be sensibly resisted 



