true, for I occasionally sounded not a few naturalists, and never
happened to come across a single one who seemed to doubt about
the permanence of species. Even Lyell and Hooker, though they
would listen with interest to me, never seemed to agree. I tried
once or twice to explain to able men what I meant by Natural
Selection, but signally failed. What I believe was strictly true
is that innumerable well-observed facts were stored in the minds
of naturalists ready to take their proper places as soon as any
theory which would receive them was sufficiently explained.
Another element in the success of the book was its moderate size;
and this I owe to the appearance of Mr. Wallace's essay; had I
published on the scale in which I began to write in 1856, the
book would have been four or five times as large as the 'Origin,'
and very few would have had the patience to read it.

I gained much by my delay in publishing from about 1839, when the
theory was clearly conceived, to 1859; and I lost nothing by it,
for I cared very little whether men attributed most originality
to me or Wallace; and his essay no doubt aided in the reception
of the theory. I was forestalled in only one important point,
which my vanity has always made me regret, namely, the
explanation by means of the Glacial period of the presence of the
same species of plants and of some few animals on distant
mountain summits and in the arctic regions. This view pleased me
so much that I wrote it out in extenso, and I believe that it was
read by Hooker some years before E. Forbes published his
celebrated memoir ('Geolog. Survey Mem.,' 1846.) on the subject.
In the very few points in which we differed, I still think that I
was in the right. I have never, of course, alluded in print to
my having independently worked out this view.