165A[.1]

[sketch]

N
45°
X
slate slate
Berkeley Sound
Slate & Sandstone
extensive low country intersected by arms from St. ??
Slate
45° 30° 40°
60°
10° 45 40°
Shale
Great valley of fragments

W E
70°
Hill 962 ft
700ft
Valley of fragments
Slate

N.B. Generally. where dips are opposite small lateral dip might also be moved in the cross valleys: but I have only put them down where best seen. —

Main range 1400 ft?
many 90°

S

Further in this direction. hills turn up in NW by W lines & quartz dips to SW by S. 40°

pencil and ink sketch, with blue watercolour.

[verso blank]

165A[.2-4]

[sketch]

[Drawn on thin tracing paper that is backed with card. These are separate slips although they were microfilmed together. The sketch is in black ink. The versos of the cards are blank.]

Fig: 1

Sandstone
Slate
Slate
NB: This not an exact representation of nature, only an illustration.

[sketch]

[Drawn on thin tracing paper that is backed with card.]

Fig: 6
A 960 ft
B
C 700 ft

useless

[sketch]

Fig: 7. [sketch in black ink on thick cream-coloured paper, verso is blank, no watermarks]

South North
Section of the great central range

useless] both instances in pencil.

165

1

My observations on the geology of the Falkland Islands were made during two visits to the Eastern Isle in the Beagle, in the months of March 1833 & 1834. At the latter of these periods I crossed from Berkle Berkeley's Sound, to Choiseul bay & returned by a longer circuit. From a series of specimens which, M^r Kent, when in the Adventure, had the kindness to collect for me at the Western island. I feel assured that the structure & geology of the whole group is of a very uniform nature. The Falkland Islands cover a space of 130 miles of Longitude by 60 of Latitude; which may be compared to the dimensions of the Isd of — Sardinia. The land is much intersected by numerous winding arms from the sea: with the exception of a few naked ridges of naked grey rock, which never attain any great elevation, the whole surface is covered by a peaty soil bearing a brown withered vegetation.

[in margin:] M^r Austen in a paper read to Geolog. Soc. says that no shells in clay-slate owing change superinduced by cleavage undermining sandstone full of shells S.Devon¹

I will now first describe the geology of the Eastern Island & particularly of the part in the neighbourhood of Berkeley's Sound. A little way inland. on the South side of this deep bay, is situated the central chain or axis of the Island; — it runs about E & W, has

¹ Austen 1842.

[continued in CUL-DAR33.166-216]