Vol. VIII, No. 9.) The Origin of Meteorites. 323 
[V.S.] 
of our original sphere. This spiral nebula will have as nucleus 
a nova or new star consisting of the core of the primordial dark 
body. As the disturbing body moves away in its course 
through space, the central nova or sun will gradually obtain 
gravitational control over its spiral nebula, forcing the constitu- 
ent parts of the nebula into closed circuits round itself as 
centre. Wherever the meteorites of the nebula are thickest 
(the knots of the nebula) they will aggregate together, forming 
‘small hot bodies that subsequently cool down into planets, 
whilst other portions of the meteoritic debris will fall into the 
central sun. 
hus, according to Lowell, was our solar system born. 
But many fragments of our primitive sphere have fallen neither 
into the sun nor into any of the planets and are still pursuing 
their course round the sun as integral units of the solar system. 
Numbers of these small bodies daily enter our atmosphere an 
are burnt up during their rapid flight. Occasionally a larger 
fragment succeeds in reaching the earth’s surface before it is 
entirely dissipated. Such fragments constitute the meteorites 
of our museums. 
hey are, as we see, if Lowell’s story is to be accepted, 
Cais ce ae ; fragments of a world that existed 
acid meteorites ”-—sPrior to the birth of the solar system, 
and are therefore older than any portion 
of this system. Our petrological investigations have demanded 
the disruption of a solid body to account for the various 
own types of meteorites. Lowell’s story of the evolution 
of the solar system provides us with such an event, and 
highest, namely 5°53.! Consequently, the ungarnered fragments 
of the original disruption'that still course round the sun between 
the inner planets must represent lower and denser shells of the 



1 Part, of course, of this difference of specific gravity is to be attri- 
buted to different degrees of condensation attained by the various 
planets. 
