986 -; Mr. R. P. Greg on Meteorolites or Aerolites, 



^se to be somewhat of the same character as that existing be- 

 tween planet and comet; the former composed of matter in a 

 solid form and revolving round the sun in orbits less elliptical 

 than the lattei'y but more so than those of the larger planets, the 

 latter having also a gaseous or perhaps fluid nature. 



Some attempts have been made to ascertain the orbirs of the 

 periodically recurring meteor showers of August and September, 

 and Professor Olmstead calculated that the one seen on the night 

 of the I3th of November 1833, had its apkelionneav the earth's 

 orbit, and its perihelion within the orbit of Mercury ; that is, its 

 mean distance from the sun lies within the earth's orbit. (See 

 Note TIL) 



An examination of Table F. will, I am persuaded, convince 

 most people that there are periodic epochs for aerolites as well 

 as for luminous meteors. This, if true, as I feel convinced 

 the sequel of future observations will prove to be the case, is 

 a new and important step gained towards a just consideration 

 of these bodies, and determines for them a place in our solar 

 system. 



I have just expressed the opinion that there probably existed 

 a difference between aerolites and luminous meteors or meteoric 

 showers, and based that opinion partly on the fact that there is 

 no increase in the number of aerolites or meteoric stones which 

 have fallen to the earth at those periods most remarkable as 

 epochs for luminous meteors; and on comparing the aerolite 

 epochs (see notes a and b, Table F.) with those for luminous 

 meteors, this opinion is still further borne out. There is, how- 

 ever, distinctly one exception, and that is November 27-29, 

 an epoch apparently common to both classes alike. It remains, 

 however, to be seen if their periods as well as epochs agree, and 

 whether those years in which the aerolites fall are also unusually 

 rich in meteors. (See Note IV.) 



Connecting as I do aerolites with the system of the asteroids, 

 and allowing that the earth, at the period of aphelion or greatest 

 distance from the sun, may be most liable to come near or in 

 contact with them, we must also consider them, like the aste- 

 roids, as having a greater mean distance than the earth from 

 the sun, i. e, as lying principally without the earth's orbit. 



I am not now proposing any new theory, but only supporting 

 and carrying out the supposition long ago entertained by 

 Dr. Chladni, and since then advocated by most astronomers, that 

 meteoric stones are true, though minute, planetary fragments ; 

 but from want of data, no serious attempt at anything amount- 

 ing to demonstrative j)roof has yet been made ; and there are 

 now many scientific men who attribute to them an atmospheric 

 or lunar origin. When, therefore, there is still so much conjee- 



