1885J Comet Systems. xgx 
seems, formed after the manner detailed above; but the 
former, although they may have been in some cases formed 
similarly, must obviously have been formed after a somewhat 
different manner. 
Let us inquire into this : — 
The orbit of Jupiter is found to be exceedingly rich in 
cometic aphelions. So thickly, indeed, do they congregate 
that not in the instance of any other planet in the Solar 
System is the peculiarity so marked. Now the eruption 
theory claims that this circumstance is thoroughly confirm- 
atory of the fadt that the Jovian comet system had its 
genesis in the interior of Jupiter’s mass. On the other 
hand, the advocates of the capture theory maintain that the 
fadts prove that comets are captured from space, and brought 
under the Sun’s attradtion in consequence of the disturbing 
adtion of the larger planets ; and certainly of the two the 
latter seems the more probable, albeit arguments have been 
recently adduced which entirely weaken its credit. But if 
comets are enlisted into the Solar System in the manner I 
have supposed, we can easily see that the mighty Jupiter 
would possess an influence over the new arrivals greater 
than that of all the other planets put together. Hence we 
should expedb their aphelions to lie in the vicinity of J upiter’s 
orbit. And thus would arise the Solar Comet Systems, 
which could easily, as in the case of Biela’s comet, increase 
the number of its component members by duplication. 
Note . — It is necessary, perhaps, to explain more fully 
those passages in which reference is made to the earlier ages 
of Solar Systems. To put the matter shortly — How do we 
know that loose matter is drawn into a planetary system 
from outer space ? In the first place, we can trace a process 
which is nothing if it is not a graduated series of world de- 
velopment. On every hand we have sure signs that evolution 
is not confined to animals and vegetables alone. And al- 
though we have never yet been able to observe the adtual 
transformation of a nebula into a star system, we have, 
nevertheless, something which amounts to almost the same 
thing, when we remember that from the irregular nebulae to 
the perfedtly formed star, or star system, the gradation of 
world development is without a break. None of those 
“ missing links ” trouble the student of the star-depths as 
they trouble those enthusiasts who — without being either 
