inquiry, that you would undoubtedly be the best, or one of the very few
men who could do so effectively.

* * * * *

_Down, Beckenham, Kent, S.E. March 24, 1871._

My dear Wallace,--Very many thanks for the new edition of your Essays.
Honour and glory to you for giving list of additions. It is grand as
showing that our subject flourishes, your book coming to a new edition
so soon. My book also sells immensely; the edition will, I believe, be
6,500 copies. I am tired with writing, for the load of letters which I
receive is enough to make a man cry, yet some few are curious and
valuable. I got one to-day from a doctor on the hair on backs of young
weakly children, which afterwards falls off. Also on hairy idiots. But I
am tired to death, so farewell.

Thanks for your last letter.

There is a very striking second article on my book in the _Pall Mall_.
The articles in the _Spectator_[87] have also interested me much.--Again
farewell.

C. DARWIN.

* * * * *

_Holly House, Barking, E. May 14, 1871._

Dear Darwin,--Have you read that very remarkable book "The Fuel of the
Sun"? If not, get it. It solves the great problem of the almost
unlimited duration of the sun's heat in what appears to me a most
satisfactory manner. I recommended it to Sir C. Lyell, and he tells me
that Grove spoke very highly of it to him. It has been somewhat ignored
by the critics because it is by a new man with a perfectly original
hypothesis, founded on a vast accumulation of physical and chemical
facts; but not being encumbered with any mathematical shibboleths, they
have evidently been afraid that anything so intelligible could not be
sound. The manner in which everything in physical astronomy is explained
is almost as marvellous as the powers of Natural Selection in the same
way, and naturally excites a suspicion that the respective authors are
pushing their theories "a little too far."

If you read it, get Proctor's book on the Sun at the same time, and
refer to his coloured plates of the protuberances, corona, etc., which
marvellously correspond with what Matthieu Williams's theory requires.
The author is a practical chemist engaged in iron manufacture, and it is
from furnace chemistry that he has been led to the subject. I think it
the most original, most thoughtful and most carefully-worked-out theory
that has appeared for a long time, and it does not say much for the
cri