METEORS OF AUGUST AND NOVEMBER. hq 



5. That in such a plane there may be an indefinite number of these irregu- 

 lar groups at various mean distances from the sun ; or there may be a tendency 

 to the formation of a continuous, or imperfect and interrupted ring, the ring 

 itself being a conic section, probably an ellipse. The ring of Saturn furnishes 

 such an analogy in a secondary system, and, according to Cassini^^ and Laplace, 

 most probably the zodiacal light in the solar system. 



Of the degree of plausibility of these hypotheses, a priori, every one must 

 judge from such analogies as have been pointed out, and others which natu- 

 rally suggest themselves. It will readily appear that if we admit them as the 

 basis of the theory of shooting stars, we may readily infer from them the ne- 

 cessity of all the phenomena which I have pointed out as deductions from the 

 established facts and statistics of meteorology. 



By the general prevalence of the first and second law we should expect that 

 a great portion of the shooting stars seen on ordinary nights, being small 

 planets or asteroids, having their perihelia inferior to Mercury, must, at the 

 time of visibility, be generally near their aphelia, and have a small space velo- 

 city, and, moving in all directions, the mean relative direction must be nearly 

 opposite the observer's true direction, and the actual velocity of any single 

 meteor resolved in the plain normal to the observer's direction must be small, 

 and must exhibit itself as a small discrepancy from the mean convergent point 

 for the evening. This character must prevail throughout the year, indepen- 

 dent of any clusters or flocks which the earth may fall in with in its orbital 

 motion. 



On the same principle of distribution of perihelia, supposing all varieties of 

 eccentricity to occur, some of these bodies, having perihelia inferior to that of 

 Mercury, must have their aphelia far superior to the earth, and, by their mean 

 distance and period, must belong to the class of superior planets. This class 

 of superior asteroids of great eccentricity, and other asteroids having perihelia 

 superior to the former, must, even with moderate eccentricities, still be consi- 

 dered as superior planets; and have, at the earth's mean distance, a true velo- 

 city greater than that of the earth; and moving in all varieties of directions, 

 though the observer's true motion in space serves to impress on them a rela- 

 tive tendency opposite to his own, still the velocity of the asteroid in the normal 

 plane being very great, the deflection of its relative direction from the mean 



«8 Schumacher's Jahrb. 1837, p. 281. 



