The universal geography : earth and its inhabitants

25G . AMAZONIA
AND LA PLATA.
from the eastern uplands. In its upper course the Taquary is joined by the
Coxim, described by all travellers as one of the most romantic streams in Brazil.
The Miranda, itself a lovely river, is also joined by a picturesque affluent, the
Aquidauana, or Mondego, which the Paraguayans claimed as the northern limit of
their territory. Descending from the Amambahy heights, it winds in long mean-
derings between wooded banks to its junction with the Miranda at the entrance
to the marshy plains of Lake Xarayes.
From the western or Chiquito side the Paraguay receives only one important
affluent, the Tucabaca or Oliden, which, after its junction with the San Rafael,
develops a chain of lagoons much obstructed bj^ dense masses of drifting vegetation.
The Otuquis, spoken of by D'Orbigny as affording a convenient navigable route
from the Argentine plains to Bolivia, was ascended in 1854 in the Wafer Witch
by Page a distance of 34 miles, when he had to return, not for lack of depth,
but because he was unable to force a passage through the dense floating vegetation.
In 1886 Fernandez reached a point 25 miles farther, when he also had to return
for the same reason. Were its discharge regulated, and its current kept clear of
aquatic plants, the Otuquis might probably become an outlet for the trade of
Bolivia. South of the Bahia Negra confluence, the section of Gran Chaco included
in the territory of Paragiiay begins on the right bank of the river. But on the
left side, the Brazilian frontier is not indicated beyond the confluence of the
river Apa, 155 miles farther south.
Climate.
The inhabited parts of Matto Grosso, lying in the heart of the continent in a
sort of trough between the Andean and Brazilian highlands, present peculiar
climatic conditions, characterised especially by a very high mean annual tempera-
ture, higher even than on the banks of the Amazons under the equator. At the
same time the oscillations of the thermometer are far more abrupt than in other
tropical regions, amounting at times to as many as 28° and even 'i'-i'^ Fahr., in the
space of twelve hours. These sudden changes are due to the winds veering round
from north-west to south-east ; or in the reverse direction from south-east to
north-west. Thus the moist currents from the Amazonian selva are often suddenly
replaced in winter by cold currents from the Argentine pampas.
On the uplands the glass falls at times to freezing point, and wayfarers have
often perished of cold in crossing the Araxa range. In March, 1822, that is, at
the end of summer, a caravan from Rio de Janeiro lost over twenty negroes in
the Rio Manso valley west of Cuj'aba.*
The rainfall, regular in summer and frequently accompanied by thunderstorms,
has not yet been accurately gauged, but appears to average at least 120 inches.
* Meteorological conditions of Cuyaba :
—
Meau.
Temperature.
Max. Jlin.
EainfaU. Eainv Days.
TO'Tahi-. 10G= Fiilir. 45^ Fahr. 4 j inches 85