To Archibald Geikie 20 December [1871]
Summary
Asks to borrow AG’s paper on denudation of flat or nearly flat surfaces ["On modern denudation", Trans. Geol. Soc. of Glasgow 3: 153-90]. CD has recently been making some observations he thinks throw a little light on the subject.
Author: | Charles Robert Darwin |
Addressee: | Archibald Geikie |
Date: | 20 Dec [1871] |
Classmark: | The University of Edinburgh Centre for Research Collections (Gen.1425/71) |
Letter no: | DCP-LETT-8112 |
To Archibald Geikie 27 December [1871]
Summary
His admiration for the papers of AG [see 8119].
Relates his recent discovery that earthworms have brought to surface no less than 161 tons of dry earth over an area of 10 acres, thus creating the conditions for significant denudation. Would welcome information about the persistence of ridges and furrows in old pasture lands ploughed centuries ago. Do they run down the slopes or transversely? Refers to [A. C.] Ramsay, [James] Croll, Elie de Beaumont, and [Henry] Johnson.
Author: | Charles Robert Darwin |
Addressee: | Archibald Geikie |
Date: | 27 Dec [1871] |
Classmark: | DAR 185: 132 |
Letter no: | DCP-LETT-8122F |
To Archibald Geikie 30 December 1871
Summary
Is obliged for valuable letter [see 8123] and encloses queries about the manner of gradual obliteration of ridges or furrows in old pasture lands in various parts of England.
Gives details of his experiment to test his observations of the downward flow of worm-casts.
Refers to [Lyon] Playfair, [A. C.] Ramsay, and AG’s edition of [J. B.] Jukes, [A student’s manual of geology, 3d ed., 1872].
Author: | Charles Robert Darwin |
Addressee: | Archibald Geikie |
Date: | 30 Dec 1871 |
Classmark: | DAR 185: 133 |
Letter no: | DCP-LETT-8125F |