"During the epoch of the phosphorites, great changes took place in animal
forms, and almost the same types as those which now exist became defined
from one another.
"Under the influence of natural conditions of which we have no exact
knowledge, though traces of them are discoverable, species have been
modified in a thousand ways: races have arisen which, becoming fixed, have
thus produced a corresponding number of secondary species."
In 1859, language of which this is an unintentional paraphrase, occurring
in the "Origin of Species," was scouted as wild speculation; at present, it
is a sober statement of the conclusions to which an acute and
critically-minded investigator is led by large and patient study of the
facts of palæontology. I venture to repeat what I have said before, that so
far as the animal world is concerned, evolution is no longer a speculation,
but a statement of historical fact. It takes its place alongside of those
accepted truths which must be reckoned with by philosophers of all schools.
Thus when, on the first day of October next, "The Origin of Species" comes
of age, the promise of its youth will be amply fulfilled; and we shall be
prepared to congratulate the venerated author of the book, not only that
the greatness of his achievement and its enduring influence upon the
progress of knowledge have won him a place beside our Harvey; but, still
more, that, like Harvey, he has lived long enough to outlast detraction and
opposition, and to see the stone that the builders rejected become the
head-stone of the corner.