After looking at the sculptures, and the coloured stucco figures which adorned the piers and inner walls, I endeavoured to establish some standard of comparison by which I might be able to form well-founded conjectures regarding their age. I thought of various ruins in Egypt and Asia Minor, then of those belonging to later periods in Italy and Great Britain, but there were such essential differences in the materials used, and the influences of the atmosphere, that it was not possible to establish any assured conclusions. Opinions formed upon the results of an examination of the temples on the mounds would be equally unsatisfactory, for some of them, especially in their interiors, were in a comparatively good condition, others were in ruins. But, there are proofs of a moderate antiquity. The lintels that once supported the walls over the doorways and other openings have completely disappeared. In only one instance, which came under my notice, were there any signs of the thick, hard beams of zapote wood which had been employed for that purpose. A broad lintel in the monastery had left its impress upon the under surface of the wall which had weighed downwards upon it. The marks of the fibre and the shape of the lintel were clearly defined upon the mortar. Dr. Coller found amongst the ruins a piece of this wood. It was exceedingly heavy and close-grained, and was of the nature of what is known, in the East Indies, by the name of iron wood. The zapote trees grow chiefly in the forests in the valley of the Usamacinta and towards the lake of Peten. When the evening drew near, I called my Indians together and entered the forest on the way back to the village. As I rode slowly forward I felt that these mysterious ruins contained a secret which has yet to be unravelled. The priests of a powerful race, having strange and unknown forms of religion, had been for centuries worshipping at these shrines. Within the sanctuaries were graven upon tablets of stone those records which, when interpreted, may throw some light upon what is now obscure.[84] CHAPTER XVI. Mounds in the valley of the Usamacinta. — Lacandones. — Catasaja. — Canoe voyage. — Rivers and Lagoons. — Alligators. — Jonuta. — Cortes’s March to Honduras. — Cannibalism. — The Mexican Emperor Guatimozin. — Palisada. — Laguna de Terminos. — Island of Carmen. — Campeachy. — Yucatan. — Pyramidal Altar. — Human sacrifices. — Tzibalché. — Maya Indians. — Arrival at Uxmal.