Of the Aztec city of Tenochtitlan, or Mexico, but little of antiquity remains, as, according to the historian of the Conquest, the place was almost entirely razed to the ground by Cortes. It is probable, however, that enduring stone edifices formed a much less considerable part of this city than has been supposed. Nevertheless, modern excavations continually lay bare portions of Aztec masonry, as well as sculptured monoliths. A short time ago a sculptured tiger, weighing eight tons, was unearthed and deposited in the museum in the capital. The principal building of the Aztec city was the great Teocalli, upon whose site the existing cathedral was built. This huge truncated pyramid has been described already. It was surrounded by a great wall, upon the cornice of which huge carved stone serpents and tigers were the emblematic ornaments. From this wall four gates opened on to the four main streets, which radiated away towards the cardinal points of the compass. Its dimensions are given as 365 feet long by 300 feet wide at the base, whilst the summit-platform was raised more than 150 feet above the level of the streets and square. Here was set the great image of the Aztec war-god, the idol of the abominable Huitzilopochtli which Cortes and his men, after their frightful hand-to-hand struggle with the Aztecs on this giddy platform, tumbled down the face of the pyramid into the streets below, among the astonished Indians. The grandeur, architecturally, of the ancient City of Mexico has probably been somewhat exaggerated by the _Conquistadores_ and subsequent chroniclers, whose enthusiasm sometimes ran riot. The ruins of Teotihuacan are situated in the north-eastern part of the valley of Mexico, some miles from the shores of Lake Texcoco and twenty-five miles from the modern City of Mexico. They are generally ascribed to the Toltecs, or, at any rate, to a civilised nation greatly previous to the Aztecs; for the ruins were abandoned and their origin unknown when these people arrived. Cortes and his Spaniards, defeated and fleeing after the terrible struggle of the _Noche Triste_, passed near to the great earth pyramids of the Sun and the Moon, which are the main structures of Teotihuacan; but even at that time they were--as they are to-day--mere mounds of earth, in which the pyramidal form has been partly obliterated by the action of time. [Illustration: PREHISTORIC MEXICO: THE PYRAMID OF THE SUN AT TEOTIHUACAN, IN THE VALLEY OF MEXICO, SEEN FROM THE PYRAMID OF THE MOON.]