Pleased by W. Stanley Jevons’ letter.

Has ordered Dr Cohn’s book.

Is sure that GHD’s energy will lead to success with work on viscous fluids.

Asks that a copy of GHD’s paper on cousin marriage be sent to Hermann Müller. J. F. McLennan admires it "as a model".

Has sent a copy [of his article on cousin marriage] to Hermann Müller.

Problem he is now working on is a tough nut: "It does not do what [James Clerk] Maxwell said it wd or ought to do".

Gives further explanations of his theory of stirps and his objections to Pangenesis, in answer to a question of CD’s.

Asks GHD to calculate average or mean heights of crossed and self-fertilised plant species.

Provides CD with a method of obtaining a numerical ratio that expresses the superiority in heights of crossed plants to self-fertilised plants.

Cancelled: duplicate of FL-1392.xml.

Personal news – is unwell.

Mentions "Twin-papers" ["Short notes on heredity, etc., in twins", J. Anthropol. Inst. 5 (1876): 324–9] sent by Galton.

Is elated by his work on the alteration in the earth’s axis and the displacement of the poles. [See 10689.]

Sends Mind. Henry Sidgwick’s article ["The theory of evolution in its application to practice", Mind 1 (1876): 52–67] is so clear it makes CD feel "a muddle-headed man". But he disagrees with Sidgwick on the origin of morality within tribes.

Is sure mathematical discussion of elevation of continents will be valued by geologists.

Writes of his "geo-mathematical" work.

Comments on the reaction of geologists to GHD’s work on elevation of continents.

His paper on the alterations of the poles and changes in level of continents is in shape.

Sends Cambridge news.

Greatly excited by the astronomical implications of his work.

Further comments on GHD’s work on the influence of geological changes on the earth’s axis.

Frank [Francis Darwin] has made a fine zoological discovery.

Is determined not to believe in GHD’s astronomical work until J. C. Adams accepts it, for he would be so disappointed if it breaks down.

Comments on an address by William Thomson (‘On the rigidity of the earth’?), which is about the same problem that GHD is working on. Is confident Thomson has overlooked some points.

All rejoice that J. C. Adams thinks well of GHD’s work and will present his paper to the Royal Society.

Gives news of his other sons.

Has received a baffling article on God, immortality, and socialism under a Darwinian point of view.

Clerk Maxwell has disagreed with CD on molecular calculations in relation to Pangenesis in Encyclopaedia Britannica article ["Atom", Encyclopaedia Britannica, 9th ed. (1875) 3: 36–49].