The plate opposite represents a pyramidal mound, holding aloft the most curious and extraordinary structure we had seen in the country. It put us on the alert the moment we saw it. We passed an entire day before it, and, in looking back upon our journey among ruined cities, no subject of greater interest presents itself to my mind. The mound is forty-five feet high. The steps had fallen; trees were growing out of the place where they stood, and we reached the top by clinging to the branches; when these were cleared away, it was extremely difficult to ascend and descend. The maguey plants cut down in making the clearing appear fallen on the steps.

A narrow platform forms the top of the mound. The building faces the south, and when entire measured forty-three feet in front and twenty feet in depth. It had three doorways, of which one, with eight feet of the whole structure, has fallen, and is now in ruins. The centre doorway opens into two chambers, each twenty feet long and six feet wide.

Above the cornice of the building rises a gigantic perpendicular wall to the height of thirty feet, once ornamented from top to bottom, and from one side to the other, with colossal figures and other designs in stucco, now broken and in fragments, but still presenting a curious and extraordinary appearance, such as the art of no other people ever produced. Along the top, standing out on the wall, was a row of death's heads; underneath were two lines of human figures in alto relievo (of which scattered arms and legs alone remain), the grouping of which, so far as it could be made out, showed considerable proficiency in that most difficult department of the art of design. Over the centre doorway, constituting the principal ornament of the wall, was a colossal figure seated, of which only a large tippet and girdle, and some other detached portions, have been preserved. Conspicuous over the head of this principal figure is a large ball, with a human figure standing up beside it, touching it with his hands, and another below it with one knee on the ground, and one hand thrown up as if in the effort to support the ball, or in the apprehension of its falling upon him. In all our labours in that country we never studied so diligently to make out from the fragments the combinations and significance of these figures and ornaments. Standing in the same position, and looking at them all together, we could not agree.

Mr. Catherwood made two drawings at different hours and under a different position of the sun, and Dr. Cabot and myself worked upon it the whole day with the Daguerreotype. With the full blaze of a vertical sun upon it, the white stone glared with an intensity dazzling and painful to the eyes, and almost realizing the account by Bernal Dias in the expedition to Mexico, of the arrival of the Spaniards at Cempoal. "Our advanced guard having gone to the great square, the buildings of which had been lately whitewashed and plastered, in which art these people are very expert, one of our horsemen was so struck with the splendour of their appearance in the sun, that he came back at full speed to Cortez, to tell him that the walls of the houses were of silver."

Our best view was obtained in the afternoon, when the edifice was in shade, but so broken and confused were the ornaments that a distinct representation could not be made even with the Daguerreotype, and the only way to make out all the details was near approach by means of a ladder; we had all the woods to make one of, but it was difficult for the Indians to make one of the length required; and when made it would have been too heavy and cumbersome to manage on the narrow platform in front. Besides, the wall was tottering and ready to fall. One portion was already gone in a perpendicular line from top to bottom, and the reader will see in the engraving that on a line with the right of the centre doorway the wall is cracked, and above is gaping, and stands apart more than a foot all the way to the top. In a few years it must fall. Its doom is sealed. Human power cannot save it; but in its ruins it gave a grand idea of the scenes of barbaric magnificence which this country must have presented when all her cities were entire. The figures and ornaments on this wall were painted; the remains of bright colours are still visible, defying the action of the elements. If a solitary traveller from the Old World could by some strange accident have visited this aboriginal city when it was yet perfect, his account would have seemed more fanciful than any in Eastern story, and been considered a subject for the Arabian Nights' Entertainments.

At the distance of a few hundred feet from this structure, in sight at the same time as we approached it, is an arched gateway, remarkable for its beauty of proportions and grace of ornament The plate opposite represents this gateway. On the right, running off at an angle of thirty degrees, is a long building much fallen, which could not be comprehended in the view. On the left it forms an angle with another building, and on the return of the wall there is a doorway, not shown in the engraving, of good proportions, and more richly ornamented than any other portion of the structure. The effect of the whole combination was curious and striking, and, familiar as we were with ruins, the first view, with the great wall towering in front, created an impression that is not easily described.

The gateway is ten feet wide, passing through which we entered a thick forest, growing so close upon the building that we were unable to make out even its shape; but, on clearing away the trees, we discovered that this had been the principal front, and that these trees were growing in what had once been the area, or courtyard. The doors of the apartments on both sides of the gateway, each twelve feet by eight, opened upon this area. Over each doorway was a square recess, in which were the remains of a rich ornament in stucco, with marks of paint still visible, apparently intended to represent the face of the sun surrounded by its rays, probably once objects of adoration and worship, but now wilfully destroyed. The plate opposite represents this front The buildings around the area formed a great irregular pile, measuring in all two hundred feet in length. The plan was different from that of any we had seen, but, having so many subjects to present, I have not had it engraved.