no THE POPULAR SCIENCE MONTHLY. 



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 Ani- 

 mal Hounds, 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 per- 

 severing labor on the surface of the soil, while enclosures and works 

 of defence are almost entirely wanting, the ancient city of Azfcalan 

 being, as is supposed, the only example of the former class. 



One remarkable group in Dale County, close to the Great Indian 

 War-path, 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 remark 

 able excavations before alluded to. One of the turtle-mounds, partial- 

 ly 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 con- 

 tents 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 an- 

 tiquity 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 re- 

 quired 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 ration- 



