in fact, a distinct line on the hillside which looks as though an azequia had once passed that way.  In the valley back of Lucre are also faint indications of old azequias.  There has been, however, a considerable amount of erosion on the hills, and if, as seems likely, the water-works have been out of order for several centuries, it is not surprising that all traces of them have disappeared in places.  I regret very much that circumstances over which I had no control prevented my making a thorough study of the possibilities of such a theory.  It remains for some fortunate future investigator to determine who were the inhabitants of Piquillacta, how they secured their water supply, and why the city was abandoned.

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Figure

Sacsahuaman:  Detail of Lower Terrace Wall
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Figure

Ruins of the Aqueduct of Rumiccolca
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Until then I suggest as a possible working hypothesis that we have at Piquillacta the remains of a pre-Inca city; that its chiefs and people cultivated the Lucre Basin and its tributaries; that as a community they were a separate political entity from the people of Cuzco; that the ruler of the Cuzco people, perhaps an Inca, finally became sufficiently powerful to conquer the people of the Lucre Basin, and removed the tribes which had occupied Piquillacta to a distant part of his domain, a system of colonization well known in the history of the Incas; that, after the people who had built and lived in Piquillacta departed, no subsequent dwellers in this region cared to reoccupy the site, and its aqueduct fell into decay.  It is easy to believe that at first such a site would have been considered unlucky.  Its houses, unfamiliar and unfashionable in design, would have been considered not desirable.  Their high walls might have been used for a reconstructed city had there been plenty of water available.  In any case, the ruins of the Lucre Basin offer a most fascinating problem.

In the Oropesa Basin the most important ruins are those of Tipon, a pleasant, well-watered valley several hundred feet above the village of Quispicanchi.  They include carefully constructed houses of characteristic Inca construction, containing many symmetrically arranged niches with stone lintels.  The walls of most of the houses are of rough stones laid in clay.  Tipon was probably the residence of the principal chief of the Oropesa Basin.  It commands a pleasant view of the village and of the hills to the south, which to-day are covered with fields of wheat and barley.  At Tipon there is a nicely constructed fountain of cut stone.  Some of the terraces are extremely well built, with roughly squared blocks fitting tightly together.  Access from one terrace to another was obtained by steps made each of a single bonder projecting from the face of the terrace.  Few better constructed terrace walls are to be seen anywhere.  The terraces are still cultivated by the people of Quispicanchi.  No one lives at Tipon now, although little shepherd boys and goatherds frequent the neighborhood.  It is more convenient for the agriculturists to live at the edge of their largest fields, which are in the valley bottom, than to climb five hundred feet into the narrow valley and occupy the old buildings.  Motives of security no longer require a residence here rather than in the open plain.