Sometimes we find a character appearing here and there as the sole remnant of a once numerous race, for example, the rare appearance in European populations of a skull of the Neanderthal type, a race widely spread over Europe 40,000 years ago, or of the Cro-Magnon type, the predominant race 16,000 years ago. Before the fossil remains of the Neanderthal and Cro-Magnon races were studied and understood such reversional specimens were considered pathological, instead of being recognized as the reappearance of an ancient and submerged type. These physical characters are to all intents and purposes immutable and they do not change during the lifetime of a language or an empire. The skull shape of the Egyptian fellaheen, in the unchanging environment of the Nile Valley, is absolutely identical in measurements, proportions and capacity with skulls found in the pre-dynastic tombs dating back more than six thousand years. There exists to-day a widespread and fatuous belief in the power of environment, as well as of education and opportunity to alter heredity, which arises from the dogma of the brotherhood of man, derived in its turn from the loose thinkers of the French Revolution and their American mimics. Such beliefs have done much damage in the past and if allowed to go uncontradicted, may do even more serious damage in the future. Thus the view that the Negro slave was an unfortunate cousin of the white man, deeply tanned by the tropic sun and denied the blessings of Christianity and civilization, played no small part with the sentimentalists of the Civil War period and it has taken us fifty years to learn that speaking English, wearing good clothes and going to school and to church do not transform a Negro into a white man. Nor was a Syrian or Egyptian freedman transformed into a Roman by wearing a toga and applauding his favorite gladiator in the amphitheatre. Americans will have a similar experience with the Polish Jew, whose dwarf stature, peculiar mentality and ruthless concentration on self-interest are being engrafted upon the stock of the nation. Recent attempts have been made in the interest of inferior races among our immigrants to show that the shape of the skull does change, not merely in a century, but in a single generation. In 1910, the report of the anthropological expert of the Congressional Immigration Commission gravely declared that a round skull Jew on his way across the Atlantic might and did have a round skull child; but a few years later, in response to the subtle elixir of American institutions as exemplified in an East Side tenement, might and did have a child whose skull was appreciably longer; and that a long skull south Italian, breeding freely, would have precisely the same experience in the reverse direction. In other words the Melting Pot was acting instantly under the influence of a changed environment.