626 Transactions of the American Institute. 



ters from Schiaparelli, of the Brera Observatory, at Milan, to 

 Father Secchi, which have been published in the Meteorological Bul- 

 letin of Rome. He believes matter is disseminated in celestial 

 spaces in all possible grades of division, from the larger stars to the 

 cosmical clouds formed in space by the local concentration of 

 celestial matter, in a manner analagous to the crystallization of sub- 

 stances chemically dissolved in liquids. A cosmical cloud cannot 

 really penetrate the interior of the solar system, unless in the form 

 of a parabolic current, which may be myriads of years in passing 

 its perihelion, like a long river having comparatively small trans- 

 verse dimensions. That part of such a current, encountered by 

 the earth in its orbital motion, appears to us in the form of 

 showers of meteors diverging at a certain radiant. A great num- 

 ber of these meteoric currents are probably moving at various 

 distances, and in various directions within the solar system, 

 sometimes passing through each other without disturbance, and in 

 other cases, by interruption, forming multiple currents, and under 

 some circumstances forming closed elliptical rings. The Novem- 

 ber meteroroids appear to be portions of such a ring now in the 

 process of formation. 



Shooting stars cannot be accounted for by supposing the exis- 

 tence of cosmical clouds having short periods of revolution, for 

 such clouds cannot, in obedience to the known laAvs of universal 

 gravitation, have a permanent existence. 



The state of dispersion of matter forming paraliolic cuiTents is 

 increased after passing the perihelion. When the current meets a 

 planet, in particular cases great perturbations may ensue, resulting 

 in a separation of some of the meteoric stars into special orbits, 

 w^hich may then be distinguished as sporades. Thus, meteoric stars 

 which were regarded by many as atmospheric phenomena, by 

 Olbers and Laplace as matter from the moon, and by more recent 

 investigators, as members of the planetary system, truly belong to 

 the category of the fixed stars; they have the same relation to comets 

 that the asteroids do to the larger planets, their great number com- 

 pensating for the smallness of the mass. A falling star, bolis, and 

 aerolite differ only in their magnitude. They are fragments of the 

 matter of which the stellar universe is formed; they contain no 

 chemical element not found on the earth; and as the revelations 

 of the spectroscope render it probable that there is a similarity of 

 composition of all visible bodies of the universe, they add a new 

 argument in favor of this view of the origin of shooting stars. 



