RECORD: Darwin, C. R. 2.1833. Geological diary: Bay. N. of Orange bay. CUL-DAR34.181-182. Edited by John van Wyhe (Darwin Online, http://darwin-online.org.uk/)

REVISION HISTORY: Transcribed by Kees Rookmaaker, corrections and editing by John van Wyhe 4.2011. RN1

NOTE: See record in the Darwin Online manuscript catalogue, enter its Identifier here. This document, part of the largest scientific document composed by Darwin during the voyage of the Beagle, is written mostly in ink. Marginal notes are here integrated into the text.

Reproduced with the permission of the Syndics of Cambridge University Library and William Huxley Darwin.

See the introduction to the Geological Diary by Gordon Chancellor.


181

Bay. N. of Orange bay. —

Rock. generally feldspathic with few few crystals of feldspar. Sometimes slaty — Othertime with angular cleavage, showing a tendency to become columnar. — (795 ?)

Traversing the Hardy peninsula

Hills not lofty, become quite irregular & generally in rough paps. protruded irregularly from the outline of the hills. A slate range would appear to run in a line with Cape Weddell & bearing from West coast WNW. All the southern part would appear to be of the following description:

rocks. very various. of 5 or 6 small hills which I ascended: one was fine hornblende: — another feldspathic with crystals of feldspar & [acecular] one of hornblende. —

Another good trap (988.) with hornblende rock with much pyrite: — another hill. was greenstone

181 verso

& feldspathic rock. — The most lofty hill was slaty feldspathic rock. — cleavage running about SE by E (true). — This is very remarkable as showing the intimate relation between this rock & the slate. — NB. these hills were surrounded on all sides by the crystalline rock. —

Another hill of large size was of a most singular nature being basaltic (easily fusible) with numerous yellow crystals. & dividing into an angular small concretionary pieces: decomposing easily the detritus consisting of their pieces. rem on a large scale columnar. but not very regular — the rock very constant in character. reminded me of volcanic rock. — I have reason to believe. that

(991. —2. 3:

182

precisely similar rock (specimen & memory of Mr Bynoes) in the gulf of Penas: This hill. as the others is quite unconnected with all others & entirely formed of this rock. Yet the surface was covered by angular fragments of several varieties of greenstone:

There is a mass of rock lying between all these hills. & which would appear to be syenite. & resembling that on the southern arm of Beagle Channell. — The irregular form of hills, if submerged would explain the numberless islands of West coast. —

I imagine all these rocks, & the whole S. — Trap formation to be slate altered: (where the hills are conical mostly fused). — Perhaps when after all the central granite chain was upheaved. we may suppose this great attention & disturbance in

182 verso

in the slate formation:

((the quantity of pyrites in hornblende rock, accounted for by the iron formation in the slate))

Guanaco by the disjunction of alluvium in Navarin island. —

The anticlinal arches & dykes of greenstone show that since the SSW elevation there has been grand disturbance

The islands in [illeg] bay greenstone (?)

T. del Fuego. —

T. del Fuego. —] written perpendicular to other entries on the page, as a heading or title to these notes.


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

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