The Aztecs had no useful domesticated animals. And we have seen that they employed bronze, as a substitute for iron, for all mechanical purposes. The bison, or wild cow of America, however, which ranges in countless herds over the magnificent prairies of the west, yields milk like the tame animal of the same species in Asia and Europe;[454] and iron was scattered in large masses over the surface of the table-land. Yet there have been people considerably civilized in Eastern Asia who were almost equally strangers to the use of milk.[455] The buffalo range was not so much on the western coast as on the eastern slopes of the Rocky Mountains;[456] and the migratory Aztec might well doubt whether the wild, uncouth monsters whom he occasionally saw bounding with such fury over the distant plains were capable of domestication, like the meek animals which he had left grazing in the green pastures of Asia. Iron, too, though met with on the surface of the ground, was more tenacious, and harder to work, than copper, which he also found in much greater quantities on his route. It is possible, moreover, that his migration may have been previous to the time when iron was used by his nation; for we have seen more than one people in the Old World employing bronze and copper with entire ignorance, apparently, of any more serviceable metal.[457]--Such is the explanation, unsatisfactory, indeed, but the best that suggests itself, of this curious anomaly. The consideration of these and similar difficulties has led some writers to regard the antique American civilization as purely indigenous. Whichever way we turn, the subject is full of embarrassment. It is easy, indeed, by fastening the attention on one portion of it, to come to a conclusion. In this way, while some feel little hesitation in pronouncing the American civilization original, others, no less certainly, discern in it a Hebrew, or an Egyptian, or a Chinese, or a Tartar origin, as their eyes are attracted by the light of analogy too exclusively to this or the other quarter. The number of contradictory lights, of itself, perplexes the judgment and prevents us from arriving at a precise and positive inference. Indeed, the affectation of this, in so doubtful a matter, argues a most unphilosophical mind. Yet where there is most doubt there is often the most dogmatism. The reader of the preceding pages may perhaps acquiesce in the general conclusions,--not startling by their novelty,-- First, that the coincidences are sufficiently strong to authorize a belief that the civilization of Anahuac was in some degree influenced by that of Eastern Asia. And, secondly, that the discrepancies are such as to carry back the communication to a very remote period; so remote that this foreign influence has been too feeble to interfere materially with the growth of what may be regarded in its essential features as a peculiar and indigenous civilization.[458] BOOK II DISCOVERY OF MEXICO