of these brilliantly white and level expanses in the midst of the brown
and desolate plain, offers an extraordinary spectacle. A large
quantity of salt is annually drawn from the salina: and great piles,
some hundred tons in weight, were lying ready for exportation. The
season for working the salinas forms the harvest of Patagones; for on
it the prosperity of the place depends. Nearly the whole population
encamps on the bank of the river, and the people are employed in
drawing out the salt in bullock-waggons. This salt is crystallized in
great cubes, and is remarkably pure: Mr. Trenham Reeks has kindly
analyzed some for me, and he finds in it only 0.26 of gypsum and 0.22
of earthy matter. It is a singular fact, that it does not serve so
well for preserving meat as sea-salt from the Cape de Verd islands; and
a merchant at Buenos Ayres told me that he considered it as fifty per
cent. less valuable. Hence the Cape de Verd salt is constantly
imported, and is mixed with that from these salinas. The purity of the
Patagonian salt, or absence from it of those other saline bodies found
in all sea-water, is the only assignable cause for this inferiority: a
conclusion which no one, I think, would have suspected, but which is
supported by the fact lately ascertained, [3] that those salts answer
best for preserving cheese which contain most of the deliquescent
chlorides.
The border of this lake is formed of mud: and in this numerous large
crystals of gypsum, some of which are three inches long, lie embedded;
whilst on the surface others of sulphate of soda lie scattered about.
The Gauchos call the former the "Padre del sal," and the latter the
"Madre;" they state that these progenitive salts always occur on the
borders of the salinas, when the water begins to evaporate. The mud is
black, and has a fetid odour. I could not at first imagine the cause
of this, but I afterwards perceived that the froth which the wind
drifted on shore was coloured green, as if by confervae; I attempted to
carry home some of this green matter, but from an accident failed.
Parts of the lake seen from a short distance appeared of a reddish
colour, and this perhaps was owing to some infusorial animalcula. The
mud in many places was thrown up by numbers of some kind of worm, or
annelidous animal. How surprising it is that any creatures should be
able to exist in brine, and that they should be crawling among crystals
of sulphate of soda and lime! And what becomes of these worms when,
during the long summer, the surface is hardened into a solid layer of
salt? Flamingoes in considerable numbers inhabit this lake, and breed
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