[Responding to HS's 1859-12-31,] JH presents additional problems in the nebular hypothesis, critiques in detail HS's views of the distribution of cometary orbits, and argues against HS's theory of sunspot formation.

[Responding to JH's 1860}-1-12,] HS admits some of JH's objections to HS's views on distribution of cometary orbits, but attempts to salvage HS's cyclonic theory of sunspot formation.

Has prepared a historical sketch [of writers on origin of species] for foreign editions of Origin. It includes HS. He was too ill to provide it for the 1st ed.

Sorry Murray has not sent HS his copy of Origin, as he was instructed.

Huxley will put CD and E. A. Darwin down for HS’s gigantic [publishing] programme. Suggests Dr Drysdale be approached about it.

CD has caused a great change in HS’s views, in showing how a great proportion of adaptation should be explained by natural selection not direct adaptation to changing conditions. HS had remarked on the survival of the best individuals as a cause of improvement in man, but he "& every one" overlooked selection of spontaneous variation. Believes so many kinds of indirect evidence must add up to a conclusive demonstration of the doctrine.

HS put the case of selection strikingly and clearly in his article [Anonymous, "A theory of population, deduced from the general law of animal fertility", Westminster Rev. 57 (1852): 468–501]. Of CD’s numerous private critics only HS has rendered the philosophy fairly: his argument is an hypothesis that explains groups of facts.

Asks JH to become a subscriber to a work that HS is bringing out. Lists prominent persons who have already done so.

Thanks JH for agreeing [1860-3-17] to be a subscriber to HS's project and for JH's critique of HS's use of the term 'Absolute.' Admits that it has difficulties.