eS ea ee: 
Recent contributions to Astro-Meteorology. 291 
gust shall be one or two days after the shower, and in February 
five or six days after the earth crosses the plane of the August 
ring? 
3. The paths and probable origin of Shooting Stars. 
The most important recent contribution to the theory of shoot- 
ing stars is by Mr. Schiaparelli of the Brera Observatory at 
Milan. It is contained in a series of five letters to P. Secchi, 
published in the Bullettino Meteorologico of Rome. 
y a course of reasoning similar to that which led the writer 
to the same conclusion,t+ he argues that the mean velocity of the 
meteoroids, is considerably greater than that of the earth in its 
eae Hence their orbits are in general, long ellipses, or parab- 
olas. 
Assuming then (which is not improbable) that the meteoroids 
form in the planetary spaces a multitude of currents, or continu- 
ous rings, having all possible inclinations to the ecliptic, he pro- 
ceeds to inquire in what way so singular a form of grouping of 
cosmical matter, could have been produced. is ae 
Notwithstanding the uncertainty of the determinations of the 
velocity of the solar system and of the stars in space, he consid- 
ers it reasonable to assume that the velocities relative to the sun 
of the various bodies which are scattered through stellar spaces, 
ane comparable in magnitude to those of the planets in their 
orbits. 
A >. ‘. 
Suppose now one of these bodies, a comet for instance, to come 
by its proper motion so near to the sun, that solar attraction far 
tance from the earth. , 
* Vol. v, Nos. 8, 10, 11, 12, and vol. vi, No. 2. oe . 
This tats xxxix, 205-7, and Mem. Nat, Acad. of Sciences, vob i, p. 309-811. 
