History indicates mysterious laws in the progress of the typical stocks of the human families; and it shows, in the colonization of the past, how frail are human calculations in migration and settlement unless based upon science. "It is not unknown to me," said the Roman soldier, two thousand years ago, when about to attack the remnant of the army of Brennus, that had passed over into Asia Minor, and conquered the land by the fierceness of their attack, and the terror of their name,--"it is not unknown to me," said Manlius, "that of all the nations inhabiting Asia, the Gauls have the highest reputation as soldiers. "A fierce nation, after overrunning the face of the earth with its arms, has fixed its abode in the midst of a race of men the gentlest in the world. Their tall persons; their long, red hair; their vast shields, and swords of enormous length; their songs also when they are advancing to action; their yells and dances, and the horrid clashing of their arrows while they brandish their shields in a peculiar manner practised in their original country,--all these are circumstances calculated to strike terror. But let Greeks, and Phrygians, and Carians, who are unaccustomed to and unacquainted with these things, be frightened by such. The Romans, long acquainted with Gallic tumults, have learned the emptiness of their parade. Our forefathers had to deal with genuine native Gauls; but they are now a degenerate, a mongrel race, and in reality what they are named, Gallogrecians. Just so is the case of vegetables, the seeds not being so efficacious for preserving their original constitution as the properties of the soil and climate in which they may be reared, when changed, are towards altering it. The Macedonians who settled at Alexandria, in Egypt, or in Seleucia, or Babylonia, or in any other of their colonies scattered over the world, have sunk into Syrians, Parthians, or Egyptians. "What trace do the Tarentines retain of the hardy, rugged discipline of Sparta? Everything that grows in its own natural soil attains the greater perfection: whatever is planted in a foreign land, by a gradual change in its nature degenerates into a similitude to that which affords it nurture. Brutes retain for a time, when taken, their natural ferocity; but after being long fed by the hands of men, they grow tame. Think ye then that Nature does not act in the same manner in softening the savage tempers of men? Do you believe these to be of the same kind that their fathers and grandfathers were? * * * "By the very great fertility of the soil, the very great mildness of the climate, and the gentle dispositions of the neighboring nations, all that barbarous fierceness which they brought with them has been quite mollified."