20 ABORIGINAL MONUMENTS
able than we, in our ignorance of the military system of the ancient people, would suppose. From the manifest judgment with which their military positions were chosen, as well as from the character of their entrenchments, so far as we understand them, it is safe to conclude that all parts of this work were the best calculated to secure the objects of the builders, under the mode of attack and defence then practised. On the assumption that the embankments of this work were crowned with palisades, it is easy to com- prehend that it afforded entire security against any assault by rude or savage foes.
The coincidences between the guarded entrances of this and similar works throughout the West, and those of the ancient Mexican defences, are singularly strik- ing. The wall on the eastern side of the Tlascallan terri- tories, mentioned by Cortez and other early writers, was six miles long, having a single entrance thirty feet wide, which was formed as shown in the supplementary plan A. The ends of the walls overlapped each other in the form of semicircles, having a common centre.*
The work above described may be taken as a very fair example of this class of structures, although nearly every work has interesting individual features, which can only be exhibited in connection with plans of the works themselves. Many are of vast dimensions ; indeed, the works of greatest magnitude are those which are most clearly of defensive
- “On leaving the territory (of Clempoallan) I met with a large wall of
dry stone, about nine feet in height, which extended across from one moun- tain to the other: it was twenty feet in thickness, and surmounted throughout its whole extent by a breastwork a foot and a half thick, to enable them to fight from the top of the wall. There was but one entrance, about ten paces wide, where one portion of the wall was encircled by the other, in the manner of a ravelin, for about forty paces. Thus the entrance was circuitous and not direct. Having inquired into the origin of this wall, I was informed it was erected on account of the place being the frontiers of the province of Tlascallas whose inhabitants were enemies of Montezuma and always at war with him.” —Second Letter of Cortez ; see also Bernal Diaz, De Solis, and Clavigero.
