Pleased ACR likes Origin. Every geological believer is most important. A long, stiff battle is ahead for the new doctrine.

Discusses poultry crosses, "what a hopelessly difficult subject is that of inheritance!" Gives details of some pigeon crosses he made; cannot positively recall which produced the blue bird.

Last sheets of AG’s review of Origin have arrived. CD’s comments and criticisms.

Comments on CL’s reaction to the Origin. Mentions reactions of other scientists.

Discusses fertility of Aspicarpa.

Criticises Herbert Spencer’s views on population.

Applauds JDH’s reply [25 Feb 1860] to W. H. Harvey in Gardeners’ Chronicle.

Asks JDH for some Goodenia.

Suggests Daniel Oliver try to cross Mimosa, noted for sterility.

Believes in the "perfect indefiniteness & frequently the vast length of the interval" between consecutive geological formations. Thus has little respect for arguments against CD based on the absence of transitional forms in the geological record. States that species found through series of beds do vary: some Silurian species have many synonyms which are really varieties of greatly differing ages. CD’s theory accounts for the progressive inprovement, multiplication and increase in complexity that can be seen, but which may often be only relative.

Returns paper by Asa Gray [? "Review of Darwin’s theory", Am. J. Sci. 2d ser. 29 (1860): 153–84].

Greatly admires Origin.

Can follow effects of natural selection in Carex, but when CD brings millions of years into play, he is like Church which demands faith. FB cannot believe in divinity of Christ, resurrection, or miracles.

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.

Sends a lithograph of the 4-ft. aperture equatorial. Has made no observations with it yet. Had difficulty with the surface of the speculum. Comments on the drawing and on the use of the instrument. Cannot recollect seeing any of the irregularities pointed out by JH in his letter.

Pointing out the reasons for some apparent discrepancies in the drawing of his telescope. The drawing was hurriedly done by his daughter.

Thanks for signing his certificate for the R.S.L. Has promise of support from members of Council. Has just contrived a new ozone box; gives details. Carrying out observations with underground thermometers.

Comments on WL's 4-foot equatorial telescope of which WL sent JH a lithograph [see WL's 1860-2-8].

Received JH's letter and enclosure of yesterday. Gave instructions to refuse newspapers arriving for JH without postage from Cape of Good Hope.

Has a foreigner staying at his house. Has seen letter by this man addressed to JH. TR wants to know if the foreigner is respectable. Thinks his name is [B.] Birkenthal.

Asks JH's opinion of a tuning fork design; includes plan of the instrument.

Thanks JH for advice on tuning fork. Further enquires about the instrument.

Sends his personal scientific journal to JH. Charles Babbage has already given JS much help.

Claims if he had known certain informations concerning discovery of Neptune, he would have ranked J. C. Adams's claim equal with U. J. J. Leverrier's.

Asks JH's opinion of placement of some of William Herschel's documents. Agrees with JH on Neptune case, although he claims to have difficulty formulating an argument.