Calendar Stone, which embodies evidence of greater knowledge, was believed by Humboldt to indicate unmistakable relations to the ancient science of South-Eastern Asia. It is of more importance here to note the shortness of the Mexican cycle, and the small amount of error in their deviation from true solar time, as compared with the European calendar at the time when the Spaniards first intruded on Montezuma’s rule. That the Spaniards were ten days in error, as compared with the Aztec reckoning, only demonstrates the length of time during which error had been accumulating in the reformed Julian calendar of Europe; and so tends to confirm the idea that the civilisation of the Mexicans was of no very great antiquity. The whole evidence supplied by Northern archæology proves that in so far as it had any civilisation of foreign origin, it must have been derived from the South, where alike in Central and in Southern America, diverse races, and a native civilisation replete with elements of progress, have left behind them many enduring memorials of skill and ingenuity. But the extremely slight and very partial traces of its influence on any people of the northern continent would of itself suffice to awaken doubts as to its long duration. The civilisation of Greece and Rome did indeed exercise no direct influence on transalpine Europe; but long centuries before the Romans crossed the Alps, as the disclosures of the lake villages, the crannoges, the kitchen middens, and the sepulchral mounds of Central and Northern Europe prove, the nations beyond their ken were familiar with weaving, and with the ceramic and metallurgic arts; were far advanced as agriculturists, had domesticated animals, acquired systems of phonetic writing, and learned the value of a currency of the precious metals. Midway between North America with its unredeemed barbarism, and the southern seats of a native American civilisation, Mexico represents, as I believe, the first contact of the latter with the former. A gleam of light was just beginning to dawn on the horizon of the northern continent. The long night of its Dark Ages was coming to a close, when the intrusion of the Spaniards abruptly arrested the incipient civilisation, and began the displacement of its aborigines and the repetition of the Aryan ethnical revolution, which had already supplanted the autochthones of prehistoric Europe.