H. C. Shetrone, Primer of Ohio Archaeology: The Mound Builders and the Indians
“ Later, when they learned that by breaking, pounding and pecking, they could change the shape and form of other stones, in making tools, the Hammer Stone was once more their servant. It was used by primitive peoples the world over, including of course the Mound-builders and the Indians. From the humble Hammer Stone, as a beginning, we may trace without a break all the inventions and progress that man has made, from the very earliest times up to the present. Therefore the Hammer Stone may be rightly called the father of civilization. ”
