Page:Popular Science Monthly Volume 55.djvu/349

This page has been validated.
THE ANTIQUITY OF MAN IN NORTH AMERICA.
333

pendicular, as would be the case if it had fallen down some root-hole, animal's or insect's burrow, or opening in the earth from any cause, and now obliterated.

Fig. 3.—Occurrence of an Argillite Implement in Glacial Stratified Sand.