year； so that you might very safely double the period as the time
during which the Pacific Ocean； the general state of the climate； and
the sea； and the temperature has been substantially what it is now； and
yet that state of things which now obtains in the Pacific Ocean is the
yesterday of the history of the life of the globe。 Those pyramids of
coral rock are built upon a foundation which is itself formed by the
deposits which the geologist has to deal with。 If we go back in time
and search through the series of the rocks； we find at every age of the
world's history which has yet been examined； accumulations of
limestone； many of which have certainly been built up in just the same
way as those coral reefs which are now forming the bottom of the
Pacific Ocean。 And even if we turn to the oldest periods of geologic
history； although the nature of the materials is changed； although we
cannot apply to them the same reasonings that we can to the existing
corals； yet still there are vast masses of limestone formed of nothing
else than the accumulations of the skeletons of similar animals； and
testifying that even in those remote periods of the world's history； as
now； the order of things implies that the earth had already endured for
a period of which our ordinary standards of chronology give us not the
slightest conception。 In other words； the history of these coral reefs；
traced out honestly and carefully； and with the same sort of reasoning
that you would use in the ordinary affairs of life； testifies； like
every fact that I know of； to the prodigious antiquity of the earth
since it existed in a condition in the main similar to that in which it
now is。
End