RECORD: Darwin, C. R. Geological diary: 'Scattered facts communicated to me by different people'. (11.1832) CUL-DAR34.12-13 Transcribed by Kees Rookmaaker, edited by John van Wyhe (Darwin Online,

REVISION HISTORY: Transcribed by Kees Rookmaaker, corrected and edited by John van Wyhe 1.2011, corrections by Jeff Ollerton 6.2011. RN3

NOTE: This document, part of the largest scientific document composed by Darwin during the voyage of the Beagle, is written mostly in ink.

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.


Scattered facts, communicated to me by different people: Novemb: 1832

The waters of the Parana are very black, as seen mingling with that of the Uruguay. — (Mr. Meggett)1 (a)

The waters of the Rio Negro very black & clear, excellent for drinking. — possess medicinal qualities causing a slight loosness at first: attribute to the Sarsaparilla. (Mr. Hughes)2

The waters of the Uruguay into which both the latter flow, pale coloured. In it, it is sand. Turtles & Crocodiles live.

Mrs. Meggett & Hughes

Riding up the West bank of the Uruguay: till you arrive in Lat: 32°. the country is flat & drinking water muddy. — at this part the soil is sandy. water. clear — the country is covered (Hence Arora del Palmas) with forests of Palm trees: it is a species with an edible tip & between 20 & 30 feet high: the land is composed of a succession of undulatory chains of granite rock these run in a North & South direction:

—Mr. Meggett.

1 John Meggett was also mentioned in the Buenos Ayres notebook, p. 10b.

2 Charles Hughes, a school fellow of Darwin's, attended Shrewsbury School, 1818-1819 and resident in Buenos Ayres, 1832-1833. He was also mentioned in the Buenos Ayres notebook.

12 verso

(a) Those who gave me this information had never read Humboldt. — How singularly do many of the facts agree, even to the popular explanation of the cause. —

The occurrence of crocodiles in the pale waters is perhaps owing to the high Lat 32° where they are found & not to the change of waters: —

Humboldt states that all the black waters are very near to the Equator: —1

Lyell. refers to Buckland about silicifying rivers P 214 Vol I1

I have seen in Mr [Rymans] possession a beautiful specimen of white silicified bone evidently of some large animal

1 Humboldt 1819-1829, vol. 5, p. 188 states: "In the vast system of rivers which we have traversed (and this fact appears to me striking) the black waters are principally restricted to the equatorial band."

2 Lyell 1830, p. 214.


The bed of the Uruguay contains abundance of silicified wood (V specimens 831 ... 834) & Concretians. — They are found at Salto & other places. — (Mr Meggett & Morris).

Also at the Rio Negro (Mr Hughes) & it is said by many that at both places. such things. as ostriches eggs, — tobacco, peach. stones, cows hoofs. &c, are also silicified?? are they only encrusted or is it an imaginary resemblance; instances which I have seen?

About 6 leagues northwards of "Bajada" (opposite Santa Fe on the Parana) "there project from a ferruginous sandstone pieces of substance resembling petrified wood." — (Mr Tweedee)1

Is it not probable that those occurring in the Uruguay owe their origin to being washed out of such beds?

There occurs in the B. Oriental South of the R. Negro. a rock which rings. — (Greenstone?)
(Mr Lumb)2

1 John Tweedie (1775-1862), Scottish gardener and plant collector based at Buenos Ayres, who owned a garden at Retiro. Tweedie was also mentioned in the Beagle field notebooks.

2 Edward Lumb (1804-75), English merchant in Buenos Ayres, also mentioned in the Beagle field notebooks.

13 verso

Salt is found in the ground south of the Plata

Mr Lumb

The Madrid Megatherium was found at Luxan said in Griffith1 to be near B. Ayres. —

Mr Oakley2 states there is a Villa de Luxan within some few leagues of the city.

Off M: Video. Beds of muscles shells. above surface of river. are they of same date as Ensenado. —

or do they denote a fall in bed of the river? —

1 Cuvier 1830 (edited by Edward Griffith), p. 133, discussed recently published bones of the head assigned to the Megatherium.

2 Mr Oakley, an American, was the agent of Woodbine Parish (1796-1882), the British consular representative. This information was first recorded in the Buenos Ayres notebook, p. 15b.

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