gh the
intervention of intermediate causes. I left this rather to be
inferred, not thinking it worth while to offend a certain class of
persons by embodying in words what would only be a speculation." (In
the same sense, see the letter to Whewell, March 7, 1837, volume ii.,
page 5:--

"In regard to this last subject [the changes from one set of animal and
vegetable species to another]...you remember what Herschel said in his
letter to me. If I had stated as plainly as he has done the
possibility of the introduction or origination of fresh species being a
natural, in contradistinction to a miraculous process, I should have
raised a host of prejudices against me, which are unfortunately opposed
at every step to any philosopher who attempts to address the public on
these mysterious subjects." See also letter to Sedgwick, January 12,
1838 ii. page 35.) He goes on to refer to the criticisms which have
been directed against him on the ground that, by leaving species to be
originated by miracle, he is inconsistent with his own doctrine of
uniformitarianism; and he leaves it to be understood that he had not
replied, on the ground of his general objection to controversy.

Lyell's contemporaries were not without some inkling of his esoteric
doctrine. Whewell's 'History of the Inductive Sciences,' whatever its
philosophical value, is always worth reading and always interesting, if
under no other aspect than that of an evidence of the speculative
limits within which a highly-placed divine might, at that time, safely
range at will. In the course of his discussion of uniformitarianism,
the encyclopaedic Master of Trinity observes:--

"Mr. Lyell, indeed, has spoken of an hypothesis that 'the successive
creation of species may constitute a regular part of the economy of
nature,' but he has nowhere, I think, so described this process as to
make it appear in what department of science we are to place the
hypothesis. Are these new species created by the production, at long
intervals, of an offspring different in species from the parents? Or
are the species so created produced without parents? Are they
gradually evolved from some embryo substance? Or do they suddenly
start from the ground, as in the creation of the poet?...

"Some selection of one of these forms of the hypothesis, rather than
the others, with evidence for the selection, is requisite to entitle us
to place it among the known causes of change, which in this cha