Some recent ethnologists have borrowed the "glacier theory" from the science of geology, in order to trace the development of civilization among certain races. In Switzerland and Greenland the signs of the action of a glacier can be traced and recognized just as we trace the proofs of the action of water in a dry channel. Visit the front of a glacier in autumn after the summer heat has made it shrink back, you will see (1) rounded rocks, as if planed on the top, with (2) a mixed mass of stones and gravel like a rubbish-heap, scattered on (3) a mass of clay and sand, containing boulders. The same three tests are frequently found in countries where there have been no glaciers within the memory of man.
Such traces, found not only in England, Scotland, and Ireland, but in northern Germany and Denmark, prove that the mountain mass of Scandinavia was the nucleus of a huge ice-cap "radiating to a distance of not less than 1,000 miles, and thick enough to block up with solid ice the North Sea, the German Ocean, the Baltic, and even the Atlantic up to the 100-fathom line." In North America the same thing is proved by similar evidence. A gigantic ice-cap extending from Canada has glaciated all the minor mountain ranges to the south, sweeping over the whole continent. The drift and boulders still remain to prove the fact, as far south as only 15° north of the tropic. A warm oceanic current, like the Gulf Stream of the Atlantic, would shorten a glacial period. Speaking of Scotland, one authority states that "if the Gulf Stream were diverted and the Highlands upheaved to the height of the New Zealand Alps, the whole country would again be buried under glaciers pushing out into the seas" on the west and east.
The theory is that as the climate became warmer, the ice-fronts retreated northward by the shrinking of the glaciers, and therefore the animals, including man, were able to live farther north. The men of that very remote period were "Neolithic," and some of the stone monuments are attributed to them that were formerly called "Druidic." A recent writer asks; with reference to Stonehenge:
Did Neolithic men slowly coming northward, as the rigors of the last glacial period abated, domicile here, and build this huge gaunt temple before they passed farther north, to degrade and dwindle down into Eskimos wandering the dismal coasts of arctic seas?
Another writer, with reference to the American ice-sheet, says:
During the second glacial epoch when the great boreal ice-sheet covered one-half of the North American continent, reaching as far south as the present cities of Philadelphia and St. Louis, and the glaciated portions were as unfit for human occupation as the snow-cap of Greenland is to-day, aggregations of population clustered around the equatorial zone, because the climatic conditions were congenial. And inasmuch as civilization, the world over, clings to the temperate climates and thrives there best, we are not surprised to learn that communities far advanced in arts and architecture built and occupied those great cities in Yucatan, Honduras, Guatemala, and other Central American states, whose populations once numbered hundreds of thousands.
An approximate date when this civilization was at the acme of its glory would be about ten thousand years ago. This is established by observations upon the recession of the existing glacier fronts, which are known to drop back twelve miles in one hundred years.
With the gradual withdrawal of the glacial ice-sheet the climate grew proportionately milder, and flora and fauna moved simultaneously northward. Some emigrants went to South America and settled there, carrying their customs, arts, ceremonial rites, hieroglyphs, architecture, etc.; and an immense exodus took place into Mexico, which ultimately extended westward up the Pacific coast.
In subsequent epochs when the ice-sheet had withdrawn from large areas, there were immense influxes of people from Asia via Bering Strait on the Pacific side, and from northwestern Europe via Greenland on the Atlantic side. The Korean immigration of the year 544 led to the founding of the Mexican Empire in 1325.
To trace then the gradations of ascent from the native American—called "Indians" by a blunder of the Great Admiral, as afterward they were nicknamed "redskins" by the English settlers—to the Mexicans, Peruvians, or Colombians is a task far beyond our strength. Leaving the question of race, therefore, we now turn to the antiquarian remains, especially the architectural.
The prehistoric civilization which was developed to the south of Mexico is generally known as "Mayan," although the Mayas were undoubtedly akin to the Aztecs or early Mexicans. The Maya tribes in Yucatan and Honduras, from abundant evidence, must have risen to a refinement in prehistoric times, which, in several respects, was superior to that of the Aztecs. In architecture they were in advance from the earliest ages not only of the Aztec peoples, but of all the American races.
In Yucatan the Mayas have left some wonderful remains at Mayapan, their prehistoric capital, and near it at a place called Uxmal which has become famous from its vast and elaborate structures,[13] evidencing a knowledge of art and science which had flourished in this region for centuries before the arrival of the Spanish. The chief building in Uxmal is in pyramidal form, the principal design in the ancient Aztec temples (as well as those of Chaldea, etc.), consisting of three terraces faced with hewn stone. The terraces are in length 575, 545, and 360 feet respectively; with the temple on the summit, 322 feet, and a great flight of stairs leading to it. The whole building is surrounded by a belt of richly sculptured figures, above a cornice. At Chichen, also in Yucatan, there is an area of two miles perimeter entirely covered with architectural ruins; many of the roofs having apparently consisted of stone arches, painted in various colors. One building, of peculiar construction, proves an enigma to all travelers: it is more than ninety yards long and consists of two parallel walls, each ten yards thick, the distance between them being also ten yards. It has been conjectured that the anomalous construction had reference to some public games by which the citizens amused themselves in that long-forgotten period. Among other memorials of Mayan architecture in this country is the city of Tuloom on the east coast, fortified with strong walls and square towers. A more remarkable "find" in the dense forests of Chiapas, in the same country, is the city recorded by Stephens and other travelers. It is near the coast, at the place where Cortés and his Spanish soldiers were moving about for a considerable time, yet they do not appear to have ever seen the splendid ruins, or to have at all suspected their existence. Even if the natives knew, the Spaniards might have found the toil of forcing a passage through such forests too laborious. The name of the city which had so long been buried under the tropical vegetation was quite unknown, nor was there any tradition of it; but when found it was called "Palenque," from the nearest inhabited village. There were substantial and handsome buildings with excellent masonry, and in many cases beautiful sculptures and hieroglyphical figures.
Merida, the capital of Yucatan, is on the site of a prehistoric city whose name had also become unknown. When building the present town, the Spaniards utilized the ancient buildings as quarries for good stones.