They had a good deal of knowledge of geometry, because it was necessary for them in measuring their lands, and for adjusting and settling the boundaries. But this was not done by measuring arcs in degrees, nor by any speculative method, but by their cords and small stones, with which they marked boundaries. I will not relate what I knew concerning them, because I did not fully understand their practices. With respect to geography, they understood very well how to paint and make models of each kingdom, and I have seen these models, with the towns and provinces depicted on them. I saw a model of Cuzco, with part of its province, and the four principal roads, made of clay and small stones and sticks. The model was according to scale, and showed the large and small squares, the streets, whether broad or narrow, the wards down to the most obscure houses, and the three streams which flow through the city. It was, indeed, a piece of work well worthy of admiration; as well as the model of the surrounding country, with its hills and valleys, ravines, and plateaux, rivers and streams with their windings, so well delineated that the best cosmographer in the world could not have done it better. They made this model that it might be seen by a person named Damian de la Bandera, who had a commission from the Royal Chancellery, to ascertain how many towns and Indians there were in the district of Cuzco.