Alfred Russel Wallace – The Voyages on the AmazonAnd murders gentle sleep.
Till, wary grown and peevish,
We’ve half a mind to weep!
But still although they torture,
We know they cannot kill –
All breathe to us in whispers
That we are in Brazil.Unaware of his brother’s fate, Alfred Wallace set out in August 1850 to explore the
upper reaches of the Rio Negro. The ‘Black River’ was so called because its waters
are coloured by tannin derived from decaying vegetation which comes from the old
and flat Guiana Shield, whereas the Amazon is a muddy white because of the huge
volumes of sediment being eroded off the mountains in the Andes. The good news is
that mosquito larvae cannot breed in the black acidic waters of the Rio Negro, hence
they were absent and Wallace noted ‘this great luxury’:
After the muddy, monotonous, mosquito-swarming Amazon, it was with great pleasure we
found ourselves in the black waters – black as ink they are, and well deserve their name;
the shores are rugged and picturesque – and greatest luxury of all, mosquitos are unknown
except on the islands.An endearing characteristic of Alfred Russel Wallace is his endless enthusiasm
under the most difficult of conditions, and
now he was excited to collect specimens
of the rare and spectacular umbrellabird
found another three days journey up the
Rio Negro. The birds have an umbrella
shaped lid of black feathers which is
perhaps the most fully developed and the
most beautiful crest of any bird known
and as Wallace writes:The Umbrella Bird is about the size of a crow,
averaging about 18 inches in length. Its colour
is entirely black, but varied with metallic
blue tints on the outer margin of its feathers
... Were it not for its crest and neck plume it
would appear to an ordinary observer nothing
more than a short-legged crow.Zoological drawing of the umbrellabird, The Descent
of Man, Charles Darwin, 1871
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