392 PROCEEDINGS OF THE OHIO ACADEMY OF SCIENCE. 



brachycephalic and dolycocephalic forms were found together. 

 On the whole the evidence supports the theory that the prehis- 

 toric earthworks of Ohio represent the outposts occupied by in- 

 vaders from the south who brought into our fertile valleys a 

 civilization higher than that attained by the tribes farther north, 

 but that their occupation was cut short by pressure of the more 

 warlike dolycocephalic tril^es. But it is no longer necessary to 

 maintain with Lewis Morgan that the mound builders were in- 

 .vaders from the far southwest and even from Mexico, who vainly 

 attempted to maintain here their village habits and organizations, 

 but found the natural conditions so unfavorable that they at 

 length abandoned the region. All the facts are sufficiently satis- 

 fied if we connect them, as Cyrus Thomas was confident we 

 should, with the Cherokees of the southern states. 



It is of more interest to note the facts bearing upon the 

 actual stage of civilization that had been attained by the mound 

 builders. Some of these facts have been known from the first 

 comprehensive explorations of the field by Squier and Davis 

 and others, who noted all the principal mounds and earthworks 

 and gave details of their form and size. Such is their size 

 and extent that they could have been constructed only by in 

 organized society of large extent. The largest mound in Ohio 

 is that at Miamisburg, which is 68 feet in perpendicular height 

 with a circumference at the base of 852 feet, which would give 

 as much as 1.300,000 cubic feet of material necessary for its 

 construction. As there is no ditch around it, or depression near 

 it from which the material could have been obtained, it must 

 have been gathered from a wide spreading surface. 



The construction of such a mound involves some interesting 

 calculations concerning the organization of society which could 

 have accomplished it. As the mound builders had no iron im- 

 plements the dirt required in the construction of the mound 

 must have been obtained and carried in a most primitive wav. 

 Allowing that each individual employed would carry a half a 

 cubic foot of soil in his basket and that he would deposit thirty 

 baskets a day, this Miamisburg mound would represent approxi- 

 mately 1,000,000 days' work so that 1000 men would be occupied 



