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110 50 feet, by 12 or 15. The usual dimensions, however, are from 5 to 8 feet.

Not the least remarkable of the American antiquities are the Animal Mounds, which are principally, though not exclusively, found in Wisconsin. In this district thousands of examples occur of gigantic basso rilievos of men, beasts, birds, and reptiles, all wrought with persevering labor on the surface of the soil, while enclosures and works of defence are almost entirely wanting, the ancient city of Azatlan being, as is supposed, the only example of the former class.

One remarkable group in Dale County, close to the Great Indian Warpath, consists of a man with extended arms, seven more or less elongated mounds, one tumulus, and six quadrupeds. The length of the human figure is 125 feet, and it is 140 feet from the extremity of one arm to that of the other. The quadrupeds vary from 90 to 126 feet in length.

"But," says Mr. Lapham, "the most remarkable collection of lizards and turtles yet discovered is on the school section about a mile and a half southeast from the village of Pewaukee. This consists of seven turtles, two lizards, four oblong mounds, and one of the remarkable excavations before alluded to. One of the turtle mounds, partially obliterated by the road, has a length of 450 feet, being nearly double the usual dimensions. Three of them are remarkable for their curved tails, a feature here first observed."

When, why, or by whom these remarkable works were erected, as yet we know not. The present Indians, though they look upon them with reverence, can throw no light upon their origin. Nor do the contents of the mounds themselves assist us in this inquiry. Several of them have been opened, and, in making the streets of Milwaukee, many of the mounds have been entirely removed; but the only result has been to show that they are not sepulchral, and that, excepting by accident, they contain no implements or ornaments.

Many computations have been made in respect to the actual antiquity of the various prehistoric remains that we have described. Sir Charles Lyell, one of the most cautious of geologists, thinks that 100,000 years is a moderate estimate of the time that has been required to form the alluvial delta of the Mississippi; and he considers that the alluvium of the Somme, containing flint implements and the remains of the mammoth and hyena, is no less ancient.

Many astronomical and climatic proofs are found of the extreme antiquity of the globe; and all geologists, indeed, are now prepared to admit that man has existed on our earth for a much longer period than was until recently supposed to have been the case.

But it may be doubted whether even geologists yet realize the great antiquity of our race. Sir Charles Lyell himself thinks that we may expect to find the remains of man in the pliocene strata, but there he draws the line, and says that in miocene time, "had some other