Will send village carrier for volumes [of the Trans. Agric. & Hortic. Soc. India].

Will visit JDH on Friday. Coming by phaeton to save five changes of conveyance.

Bernhard Studer has been at Down. Studer will not be able to join HDelaB’s Ordnance Survey working party.

CD is glad to hear about very old rocks under Silurians. "There is something grand and mysterious at these depths."

Writes concerning Charles Stokes’s purchase of stock in the Leeds and Bradford Guaranteed Railway.

Is glad that JW III is settled for life at Leith Hill Place.

Returns JFR’s copies of Transactions [Agric. & Hortic. Soc. India]. Has not found quite as much as he thought he might on varieties of Indian domestic animals and plants; "the attempts at introduction have been too recent for the effects, if any, of climate to have been developed". Is impressed by the work of the English in India.

Questions Mrs W on difference in flight capacity of male and female silkworm moths and asks her for results of experiments he suggested she do with silkworms to determine hereditariness of dark "eyebrows". [See Variation 1: 302.]

Discusses David Milne’s Glen Roy paper ["On the parallel roads of Lochaber", Trans. R. Soc. Edinburgh 16 (1849): 395–418]. Rejects Milne’s theory that outlet of Glen Roy is blocked by detritus. Impressed by Milne’s discovery of an outlet at the level of the second shelf. Believes this strengthens theory that lakes were formed by glacier blocking Glen Roy. Offers arguments against glacier theory.

Agrees to lease land to Mr Mason. Discusses arrangements for bank draft.

David Milne’s attack on his Glen Roy paper ["On the parallel roads of Lochaber", (1847) Trans. R. Soc. Edinburgh 16 (1849): 395–418] made CD horribly sick.

Wants Thomas Thomson to establish geographical range of erratic boulders in India.

Comments on David Milne’s paper ["On the parallel roads of Lochaber" (1847), Trans. R. Soc. Edinburgh 16 (1849): 395–418]. CD still believes in marine origin. Rejects barrier of detritus at mouth of Glen Roy. If roads were formed by lake, it must have been ice-lake.

Comments on evidence of glaciers and icebergs in North Wales. Thinks pass caused by tidal channel, not river. Suggests that RC make altitude measurements at various points.

Comments on paper by DM ["On the parallel roads of Lochaber", (1847) Trans. R. Soc. Edinburgh 16 (1849): 395–418]. "I am not in the least convinced about the Barriers … [but] I am very much staggered in favour of the ice-lake theory of Agassiz & [William] Buckland." Will "send a letter to the Scotsman, in which I give briefly my present impression".

Cites facts mentioned in South America possibly of use to DM.

Comments on article by David Milne ["On the parallel roads of Lochaber" (1847), Trans. R. Soc. Edinburgh 16 (1849): 395–418]. Refers to his paper on Glen Roy [Collected papers 1: 87–137]. Comments on Louis Agassiz’s article ["The glacial theory and its recent progress", Edinburgh New Philos. J. 33 (1842): 217–83]. Cites his own observations on glaciers in N. Wales. Discusses possibility of ice barrier creating lake. Notes objections to theory of an ice barrier. Defends his own theory that the roads are sea-beaches. Suggests questions for further investigation.

Mystified by the origin of coal-plants.

Milne’s Glen Roy theory is absurd but, oddly, it has staggered CD in favour of Agassiz’s ice-lake theory.

Flattered by JBJ’s discussion of coral reefs [in Voyage of H.M.S. "Fly" 1 (1847): 347–8]. CD has always thought his Coral reefs "too bold and speculative", so he is gratified "when anyone who has had opportunities of observation does not give his verdict against it".

Discusses enclosed figures on elevation of terraces in several Scottish glens as surveyed by William Kemp and David Stevenson. Comments on Robert Chambers’ view of the terraces. Mentions a letter on the terraces, originally written for publication, which he has asked Robert Jameson [editor of the Edinburgh New Philos. J.] to destroy.

Difficulty of scheduling visit before JDH departs on Himalayan expedition.

Thanks for a suite of male and female specimens of Lepidoptera. Lack of difference in size of wings surprises CD; the female’s being smaller than male’s in early growth is new to him. Will ask a friend in India for comparable facts.

On scheduling farewell meeting.

Continued problems in scheduling farewell meeting.

CD very ill; tries to arrange departure meeting with JDH.

CD’s guess at composition of Maldive flora.