Wants to go over remainder of species sketch when he sees JDH.

Urges JDH to go to Scotland.

Pleased JDH works on geographical distribution of Van Diemen’s Land flora.

Planning a visit to Kew. Wishes to meet H. C. Watson.

Invites BS to visit Down. Advises him to call on Daniel Sharpe. Suggests he see the work of the Ordnance Survey in Wales.

Offers to lend him Murchison’s The Silurian system [3 vols. (1839)].

CD thanks JFR for remembering about the work he wanted to borrow [Trans. Agric. & Hortic. Soc. India].

Does JFR have Ambrose Blacklock, Treatise on sheep [1838]?

Sends a letter for JW to forward to Charles Stokes concerning the purchase of Leeds and Bradford railway shares for Emma Darwin’s trust fund.

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."

Discusses the buying and selling of certain railway shares.

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.

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.

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 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.

Reorders six 2–oz bottles with corks.

Thanks Mrs Lyell for barnacle specimens.

Mentions Agassiz’s classification of saurians.

Discusses letter from Chambers on "roads" in Scottish glens; views of Agassiz and Buckland on the glens.

Is reading Hugh Miller [First impressions of England and its people (1847)].

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.