teeth the universally admitted theory of the undulation of light,--neither
the undulation nor the very existence of ether being proved, yet admitted
because the view explains so much. You are one of the very few who have
seen this, and have now put it most forcibly and clearly. I am much
pleased to see how carefully you have read my book, and, what is far more
important, reflected on so many points with an independent spirit. As I am
deeply interested in the subject (and I hope not exclusively under a
personal point of view) I could not resist venturing to thank you for the
right good service which you have done.

I need hardly say that this note requires no answer.


LETTER 125. TO J.D. HOOKER.

(125/1. Parts of this letter are published in "Life and Letters," II.,
page 362.)

Down, [April] 23rd, [1861].

I have been much interested by Bentham's paper in the "Natural History
Review," but it would not, of course, from familiarity, strike you as it
did me. (125/2. This refers to Bentham's paper "On the Species and Genera
of Plants, etc." "Nat. Hist. Review," April, 1861, page 133, which is
founded on, or extracted from, a paper read before the Linn. Soc., November
15th, 1858. It had been originally set down to be read on July 1st, 1858,
but gave way to the papers of Darwin and Wallace. Mr. Bentham has
described ("Life and Letters," II., page 294) how he reluctantly cancelled
the parts urging "original fixity" of specific type, and the remainder
seems not to have been published except in the above-quoted paper in the