62 
meaning of the word, evolution, when it is made to denote the 
tendency of an inert nebula to roll itself up into one mig y 
06 LetuT now take Professor Haeckel's account of the nebular, 
or as he calls it, Kant’s cosmological gas theory. It leads a 
^“Kant’s cosmogony maintains that the whole universe, in- 
conceivable ages ago, consisted of a gaseous c ^os. All 
substances found at present deposited on the eaith, and other 
bodies, originally constituted one single homogeneous mass, 
equally filling up the space of the universe, which, in con- 
sequence of an extremely high degree of temperature, was m 
an exceedingly thin gaseous or nebulous state. I he millions 
of bodies which at present form the different solar systems 
did not then exist. They originated in consequence ot a 
universal rotation, during which a number of masses acquired 
a o-reater density than the remaining mass, and these acted as 
central points of attraction. There arose a separation of the 
primary nebula into a number of rotating nebulous spheres 
While the centripetal force attracted the rotating particles 
nearer and nearer to the central point of the nucleus, the 
centrifugal force always tended to separate the peripheral pa - 
Ss farther from it. . . . As these simple processes repeated 
themselves over and over again, there arose the different solai 
systems, the planets revolving round their suns, and the 
satellites, or moons, round the planets.” i, q 
Such is the outline given of Kant s, more usually ca 
Laplace’s, theory. The merit is claimed for it that it is purely 
monistic, and entirely excludes every supernatural process, 
and pre-arranged and conscious action ot a personal Creator. 
But its high excellence as an atheistic theory is not without 
its shadow. Some weak points, Professor Haeckel observes, 
still remain, which prevent our placing m it unconditiona 
confidence, and these are stated as follows . 
“ The theory furnishes no starting-point at all m explana- 
tion of the impulse which caused the first rotary motion m the 
ffas-filled universe. In seeking for such an impulse, we are 
involuntarily led to think of a first beginning. But we can as 
little imagine a first beginning of the motion of the universe 
as of its final end. The universe is unlimited and immeasur- 
able, both in space and time. It is eternal, and it is infinite. 
Nor can we imagine a beginning or an end to the eternal 
motion, in which all the particles of matter are always engaged. 
The great laws of the conservation of force and ot matter 
admit of no othor supposition. The universe is a connected 
