As the valley of the river from age to age grew in elevation by deposits of sediment, a new growth of cypress was produced, and is now supervened by the live-oak plain, so called, which has had an existence, as estimated by the annual rings of the oaks, of fourteen thousand years.
In excavating for gas-works at New Orleans, a human skull was found beneath the roots of a cypress belonging to the fourth-forest level, in a good state of preservation, while the other bones of the skeleton crumbled to dust on exposure to the air. The type of the cranium was that of the aboriginal American. Now, if we take the period required to form the live-oak level, and add it to the time required to produce the next three subterranean growths of cypress, which overlie the fourth growth, in which the cranium was found, it clearly proves that the human race existed in the great valley of the Mississippi more than fifty-seven thousand years ago.
Not only in the valley of the Mississippi have fossil remains of man and animals been discovered at depths and in formations that prove their remote antiquity, but in many other parts of the world. Not many years ago, a human skull was found in Brazil, embedded in a sandstone rock overgrown with lofty trees. There is still preserved, in the museum at Quebec, a human skull which was excavated from the solid schist-rock on which the citadel now stands. Human skeletons have also been found in the island of Guadeloupe, embedded in a rock said to be as hard as the finest statuary marble. Even so recently as the year 1868, while sinking a well at the Antelope station, on the Union Pacific Railroad, the workmen penetrated a rock six feet thick, and at eighty feet below the rock discovered a human skeleton in such a state of preservation as to be readily recognized as such.
In another instance it is said that a human skull was discovered in Calaveras County, Cal., at the bottom of a shaft which had been sunk one hundred and thirty feet below the surface. It was found deposited in a bed of gravel with other organic remains, and beneath the eighth distinct geological layer of earth and gravel, where it must have lain, according to the estimate of Professor Whitney, the geologist, for a period of at least one hundred thousand years. This remote antiquity of man is also confirmed by discoveries in every part of the world of the fossil remains of domestic animals as well as of man, including implements of human invention, such as flint arrow-heads, stone axes, war-weapons, cooking-utensils, in localities which preclude the idea of their belonging to an age that has a written history.