446 NATURAL HISTORY MISCELLANY. 
however, on the coast, by hot and almost impassable deserts, and in the 
interior by lofty mountains, or cold and trackless punas. They had but 
little intercourse or political dependence, and they all, when by means of 
alliance or conquest the enterprising families around Cuzco became con- 
solidated, fell an easy prey to those inhabitants of the high, strong fast- 
"icta or Mns of iym ndes. From their dominating position the 
Inc ere enabled to throw overwhelming forces successively on the 
Vom ses edu from their mountain centre, hes one by one 
inold them into the grandest of aboriginal American Empires. Itis easy 
o see how ambition, and the exigences arising out of cipit aggressions, 
Should have poe gents that astute policy or statesmanship, that 
ability in organization and admimistration, of which the Incas furnished 
nple. 
That portion of a Andean plateau lying ara the Pass of La Raya, 
at the northern extremity of the Titicaca basin and the Pass of la Banda, 
near Pasco, is a great mountain-encircled region, drained by the River 
viais itself, as we have seen, formed by the hierga Apsaons and 
as flowin 
n 
the waters collected in numberless vales among the mountains. Nothing 
better describes these vales than the Spanish word bolson, or pocket. 
nd, as I have said, while the valleys of the coast are separated by des- 
erts, de ese bolsones are isolated by ranges of bills, mountains, or unin- 
habitable punas, and all these are divided into groups by the great rivers, 
which, like the Apurimac, are intransitable except by the aid of bridges 
of mimbres, or ropes swinging dizzily in mid-air 
The olsones are of varying altitudes and dosssdueatly of various 
climates and productions. Some are well-drained, others are marshy, 
and contain considerable lakes. They discharge their gathered waters, 
often in large streams that plunge, in numberless cataracts, through dark 
and narrow ravines into the gorges of the great rivers. The passage 
one b a 
punas, frequently among frost and snow, mea y ways by rocky and diffi- 
cult paths, fit only for the goat and the llam 
It was in precisely one of these bolsones, D central one of a group or 
cluster lying between the Vileamayo River and the Apurimac, that the 
their career of conquest by reducing the people of the bolson of Anta or 
Xaxiguana on the north, and of Urcos or Andahuaylillas on the south. 
