No fossil bones have been found in the cavern, nor human remains except in one of the passages far within, where a little wooden cross still marks the spot where the skeleton of an Indian was found. Whether he went alone for mere curiosity to explore the cave, or, what is more likely, with an idea of finding treasure, is not known; nothing is certain but that his candle was burnt out while he was still far from the entrance, and that he died there. I said no fossil remains had been found, but the level floors of the great halls are continually being raised by fresh layers of stalagmite from the water dropping from the roof, and no one knows what may lie under them. These floors are in many places covered with little loose concretions like marbles, and these concretions in the course of time are imbedded in the horizontal layers of the same material. As we left the entrance hall and began to ascend the sloping passage that leads to daylight, we saw an optical appearance which, had we not seen it with our own eyes, we could never have believed to be a natural effect of light and shade. To us, still far down in the cave, the entrance was only illuminated by reflected light; but as the Indians reached it, the direct rays of sunlight fell upon them, and their white dresses shone with an intense phosphoric light, as though they had been self-luminous. It is just such an effect that is wanting in our pictures of the Transfiguration, but I fear it is as impossible to paint it upon canvas as to describe it in words. Next morning our friend Don Guillermo said good-bye to us, and started to return post-haste to his affairs in the capital. We stayed a few days longer at Cocoyotla, never tiring of the beautiful garden with its groves of orange-trees and cocoanut-palms, and the river which, running through it, joins the stream that we heard rushing along in the cavern, to flow down into the Pacific. On Sunday morning the priest arrived on an ambling mule, the favourite clerical animal. They say it is impossible to ride a mule unless you are either an arriero or a priest. Not that it is by any means necessary, however, that he should ride a mule. I shall not soon forget the jaunty young monk we saw at Tezcuco, just setting out for a country festival, mounted on a splendid little horse, with his frock tucked up, and a pair of hairy goat-skin _chaparreros_ underneath, a broad Mexican hat, a pair of monstrous silver spurs, and a very large cigar in his mouth. The girls came out of the cottage doors to look at him, as he made the fiery little beast curvet and prance along the road; and he was evidently not insensible to the looks of admiration of these young ladies, as they muffled up their faces in their blue rebozos and looked at him through the narrow opening.