vii THE ANTIQUITY AND ORIGIN OF MAN 425 



The island containing these remarkable works of art has 

 only an area of about thirty square miles, or considerably less 

 than Jersey. Now, as one of the smallest images (eight feet 

 high) weighs four tons, the largest must weigh over a 

 hundred tons, if not much more ; and the existence of such 

 vast works implies a large population, abundance of food, and 

 an established government. Yet how could these coexist on 

 a mere speck of land wholly cut off from the rest of the 

 world ? Mr. Mott maintains that these facts necessarily 

 imply the power of regular communication with larger islands 

 or a continent, the arts of navigation, and a civilisation much 

 higher than now exists in any part of the Pacific. Very 

 similar remains in other islands scattered widely over the 

 Pacific add weight to this argument. 



North American Earthworks 



The next example is that of the ancient mounds and 

 earthworks of the North American continent, the bearing of 

 which is even more significant. Over the greater part of the 

 extensive Mississippi valley, four well-marked classes of these 

 earthworks occur. Some are camps, or works of defence, 

 situated on bluffs, promontories, or isolated hills ; others are 

 vast inclosures in the plains and lowlands, often of geometric 

 forms, and having attached to them roadways or avenues 

 often miles in length ; a third are mounds corresponding to 

 our tumuli, often seventy to ninety feet high, and some of 

 them covering acres of ground ; while a fourth group consists 

 of representations of various animals modelled in relief on a 

 gigantic scale, and occurring chiefly in an area somewhat to 

 the north-west of the other classes, in the plains of Wisconsin. 



The first class the camps or fortified inclosures re- 

 semble in general features the ancient camps of our own 

 islands, but far surpass them in extent. Fort Hill, in Ohio, 

 is surrounded by a wall and ditch a mile and a half in length, 

 part of the way cut through solid rock. Artificial reservoirs 

 for water were made within it, while at one extremity, on a 

 more elevated point, a keep is constructed with its separate 

 defences and water-reservoirs. Another, called Clark's Work, 

 in the Scioto valley, which seems to have been a fortified 

 town, incloses an area of 127 acres, the embankments measur- 



