RECORD: Darwin, C. R. 1857.03. [Note on denudation of the Weald]. CUL-DAR205.9.346. Edited by John van Wyhe (Darwin Online, http://darwin-online.org.uk/)

REVISION HISTORY: Transcribed by Christine Chua and edited by John van Wyhe 8.2020. RN1

NOTE: Darwin made and revised estimates in chapter IX of Origin, most famously in his discussion of the denudation of the Weald.

Reproduced with the permission of the Syndics of Cambridge University Library and William Huxley Darwin. The volume CUL-DAR205.9 contains notes on palaeontology and geology [regarding theory of evolution].


1

North side Wealden Denudation

Chalk at North side    600 ft                    600

Upper Greensand      60-80 ft                 70

Gault                      80 to 110 ft            90

Lower Greensand      350 ft                     350                        22 miles                                                                                     --------

                                                          1115

South side  March 1857 [In] almost seen with V [illeg]

Chalk on S side        700 to 800                                  750

Upper Greensand      50 feet (outside)                         40

Gault    Greensand at 80 to 100                                    90

Lower Greensand probably about 200 ft                        200

                                                                             -------

                                                                             1080

1 y [year] 1100 feet thick, & the denudation of Wealden seen not included. – It is 22 miles

From edge to edge of Wealden is & much further

East [edge to edge] & then is strips of miles or two on each side to Chalk, but we will say only 22 miles.    

Miles from edge to edge of Wealden. 

Land                                                   1760 yards to north

-  22   as we suppose & [with] of cliff – 500 ft

3520             in century cliff of 1100 feet wide

3520.            take 220 years

                             Rivers [illeg] when dry  38720

                                                               36

232320

Land   116160.

1393926 inches

       220

27878400

2787840.306, 862, 400 million years times [illeg]


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Citation: John van Wyhe, ed. 2002-. The Complete Work of Charles Darwin Online. (http://darwin-online.org.uk/)

File last updated 25 September, 2022