384 THE BEAUTIES OF NATURE CHAP. 
the meteors, which fall in showers on to the 
Sun, replace the heat which is emitted. To 
some slight extent perhaps they do so, but the 
main cause seems to be the slow condensation 
of the Sun itself. Mathematicians tell us 
that a contraction of about 220 feet a year . 
would account for the whole heat emitted, and 
as the present diameter of the Sun is about 
860,000 miles, the potential store of heat is 
still enormous. 
To the Sun we owe our light and heat; it 
is not only the centre of our planetary system, 
it is the source and ruler of our lives. It 
draws up water from the ocean, and pours it 
down in rain to fill the rivers and refresh the 
plants; it raises the winds, which purify the 
air and waft our ships over the seas; it draws 
our carriages and drives our steam-engines, 
for coal is but the heat of former ages stored 
up for our use; animals live and move by the 
Sun’s warmth; it inspires the song of birds, 
paints the flowers, and ripens the fruit. 
Through it the trees grow. For the beauties 
of nature, for our food and drink, for our 
clothing, for our light and life, for the very 
