GHD explains conduction, radiation, and convection.

His paper on political economy for Royal Institution lecture has reached 60 pages. Plans to send it to Contemporary Review.

Writes about instructions to compositor and return of proofs [of Descent]. Requests return of 2d volume of Descent, to which he may want to refer.

Thanks GHD for clear lecture on heat.

Will keep paper on proportion of sexes, in case GHD wants it again.

Wants him to translate some pages of Swedish or Norwegian sent by A. W. Malm, "a good man".

Glad to see the statistical paper ["Theory of exchange value", Fortn. Rev. n.s. 17 (1875): 243–53].

Thanks CD for Descent, 2d ed.

Comments on German edition of CD’s collected works.

Sales of his Anthropogenie [1874] in various countries.

Anticlericalism and progress of Darwinism in Germany.

On German translation of Descent [3d German, 2d English ed.]. Lists some misprints in proofs.

Forwards a photograph he thought had been lost. Has noticed that the two sides of the face are often asymmetric in portrait busts and statues.

Discusses expression on two halves of the face. Mentions photograph [of picture by Rubens].

Thanks for CD’s favourable opinion of his book [Les fourmis de la Suisse (1874)]. Habits of ants; observations on their carrying empty eggs.