The rock walls between these are banked up and faced with rock, coated with plaster and mud; there are many pyramids and mounds; there are also curious subterranean, stone-faced, graves.

Many curious disks of stone were found, a foot or eighteen inches in diameter, and three or four inches thick; these were all reddish grit, and had plainly been piled one upon another to form pillars.

Along the forward edge of some of the terraced platforms, we found the lower discs of some columns still in place.

While the amount of work, represented in these cut terraces, banked rocks, and subterranean constructions, impressed us greatly, it was difficult to get a clear idea of the relationship of the parts.
[Illustration: CACTUS NEAR CUICATLAN] [Illustration: VIEW IN A TLAXCALAN BARRANCA] When, however, we found ourselves at the station, waiting for the train, we looked back across the river to our three ruin-crowned hills.

Then, for the first time, having visited the spot, we could clearly make out the relations.