The Navajos are fairly good labourers, and the Mokis carry all their wood from forests fifteen miles away. It is work to carry water up the cliffs where the Mokis live, it is work to hoe the corn, it is work to tend and herd sheep. On full investigation it seems strange that it should ever have been thought that the mounds were not “Indian” because they represented work. Fowke has estimated that a mound a hundred feet in diameter and twenty feet high could have been erected by the “Indians” in forty-two days. I have seen Uingkaret Utes in Arizona carry on their backs with ease for twelve or fifteen miles loads that would average about thirty or forty pounds. People who can do this could carry earth in short stretches for forty or fifty days. It is probable, however, that the mounds were not built by steady and consecutive labour, but rather by intermittent effort, after the usual fashion of Amerindian work. [Illustration: BACK OF VOTIVE ADZ For front and side see page 339 From _Monumental Records_ ] [Illustration: PATTERNS OF ANCIENT FABRICS FROM POTTERY From New York From Illinois From Tennessee See page 108 ] Many mounds and earthworks were erected for defensive purposes at points controlling river passages or trails, where the advance of foes invading a country could be checked. There were also fortification works like the so-called “hill-forts” of the eastern portion of the United States, and the “cérros trinchéras” of northern Mexico. Quoting again from Thomas,[308] one of the best authorities on mounds and “Moundbuilders”: “The most extensive example of the ‘hill-forts’ is that known as Fort Ancient, in Warren County, Ohio. This crowns a spur of the bluff some two hundred and fifty or three hundred feet high, which here overhangs the Miami River. The area embraced is only some seventy-five or eighty acres, but the length of the wall, which follows all the windings and zigzags of the margin of the bluff and of the side ravines, is a little over three miles and a half. This is one of the best-preserved monuments of the Ohio valley, the surrounding wall being uninjured save at points where the turnpike cuts through it, and at a few places where ravines have been formed since it was abandoned. This wall, which is partly of stone, but chiefly of dirt thrown up from the inner or upper side, varies in height from three or four to nineteen feet, and from twenty-five to seventy feet in width at the base. As the earth has all been taken from the inside (except along the high wall which crosses the level at the rear) and thrown outward on the crest of the slope, this has left an inside ditch. As a rule, the wall is strongest and highest at the points of easiest approach; and at some places the outside slope has been artificially steepened, proving beyond any reasonable doubt that the work was one of defence.” [Illustration: ESKIMO MECHANICAL TOY.]