148 FORMATION OF CORAL REEFS. 
CHAPTER XI. 
FORMATION OF CORAL REEFS. 
Amone the astounding discoveries of modern 
science is that of the immense periods which 
have passed in the gradual formation of our 
earth. So vast were the cycles of time preceding 
even the appearance of man on the surface of 
our globe, that our own period seems as yester- 
day when compared with the epochs that have 
gone before it. Had we only the evidence of the 
deposits of rock heaped ‘above each other in regu- 
lar strata by the slow accumulation of mate- 
rials, they alone would convince us of the long 
and slow maturing of God’s work on the earth; 
but when we add to these the successive popu- 
lations of whose life this world has been the 
theatre, and whose remains are hidden in the 
rocks into which the mud or sand or soil of what- 
ever kind on which they lived has hardened in 
the course of time, —or the enormous chains of 
mountains whose upheaval divided these periods 
of quiet accumulation by great convulsions, — 
or the changes of a different nature in the con- 
