We will describe one more class of ruins found abundantly in the Collao
region. These are burial towers, or chulpas. A view of one is here
presented. The chulpas are common in the Titicaca basin, and usually
occur in groups, and almost always in positions from which a large
extent of country can be viewed. The great mass of a chulpa is solid,
but within is a dome-shaped chamber, into which the opening seen in the
cut leads. Sometimes the chulpas are round, and in some the masonry is
of that variety we have already mentioned, called the Cyclopean. Another
view of burial towers is given earlier in this chapter.

Illustration of Burial Tower.--------------------

As a mere description of ruins becomes tiresome, we will now pass to
Cuzco, and see of what we can learn of the architecture of the Incas.
The Incas were, of course, a very rich and a very powerful tribe. All
the tribes of ancient Peru had to pay them tribute. We way therefore
suppose that the pueblo of Cuzco was well built, the houses large,
and imposing, and that the official buildings for worship and tribal
business would be commensurate with their importance as a tribe. Yet
we have but very few accounts of these buildings. Immediately after the
conquest, many of the Spanish leaders settled in Cuzco. They made
many changes in the various edifices, and introduced into them many
improvements. At present in the modern city we still find portions of
ancient walls, and can trace the foundation of various buildings.

Illustration of Terrace Wall at Cuzco.---------------

The site of the city of Cuzco is very uneven. It stands on the slopes of
three hills, where as many rivulets come together. The ancient builders
had to resort to extensive terracing in order to secure level surfaces
on which to build. These terraces, built in a substantial manner,
and faced with stone, are still standing in many places. In this
illustration we have a view of such a wall. Observe that the stones are
not laid in regular courses, nor is there any regularity as to their
size. This is a good example of a Cyclopean wall. Some of the stones
must weigh several tons, and they are fitted together with marvelous
precision, one stone having as many as twelve angles.

All accounts agree that the temple of the sun was the grandest structure
in Cuzco. We present an illustration of one end of it. This end is
slightly curving. It is necessary to remark that this end now forms part
of