subterraneous galleries communicated with the city and the palaces of the
Inca.21

The fortress, the walls, and the galleries were all built of stone, the heavy
blocks of which were not laid in regular courses, but so disposed that the
small ones might fill up the interstices between the great. They formed a
sort of rustic work, being rough-hewn except towards the edges, which
were finely wrought; and, though no cement was used, the several blocks
were adjusted with so much exactness and united so closely, that it was
impossible to introduce even the blade of a knife between them.22 Many
of these stones were of vast size; some of them being full thirty-eight feet
long, by eighteen broad, and six feet thick.23

We are filled with astonishment, when we consider, that these enormous
masses were hewn from their native bed and fashioned into shape, by a
people ignorant of the use of iron; that they were brought from quarries,
from four to fifteen leagues distant, 24 without the aid of beasts of burden;
were transported across rivers and ravines, raised to their elevated
position on the sierra, and finally adjusted there with the nicest accuracy,
without the knowledge of tools and machinery familiar to the European.
Twenty thousand men are said to have been employed on this great
structure, and fifty years consumed in the building.25 However this may
be, we see in it the workings of a despotism which had the lives and
fortunes of its vassals at its absolute disposal, and which, however mild in
its general character, esteemed these vassals, when employed in its
service, as lightly as the brute animals for which they served as a
substitute.

The fortress of Cuzco was but part of a system of fortifications established
throughout their dominions by the Incas. This system formed a prominent