428 THE BEAUTIES OF NATURE CHAP, 
lapse of time is a grander element in Astron- 
omy even than in Geology, and dates back 
long before Geology begins. We must figure 
to ourselves a time when the solid matter 
which now composes our Earth was part of 
a continuous and intensely heated gaseous 
body, which extended from the centre of the 
Sun to beyond the orbit of Neptune, and 
had, therefore, a diameter of more than 
6,000,000,000 miles. 
As this slowly contracted, Neptune was 
detached, first perhaps as a ring, and then as a 
spherical body. Ages after this Uranus broke 
away. 
Then after another incalculable period 
Saturn followed suit, and here the tendencies 
to coherence and disruption were so evenly 
balanced that to this day a portion circulates 
as rings round the main body instead of being 
broken up into satellites. Again after succes- 
sive intervals Jupiter, Mars, the Asteroids, 
the Earth, Venus, and Mercury all passed 
through the same marvellous phases. The 
time which these changes would have re- 
quired must have been incalculable, and they 
ee ee ee os 4 a Say 
