The fine-grained quartzite was also in request, especially for the manufacture of the largest class of implements, including hoes and spades, equally needed by the primitive agriculturist, and by the navvies to whose industrious toil the vast earthworks of the Ohio valley are due. The site of the old quartzite quarry appears to be about eight miles from the banks of Saline river; but there are many other localities scattered over the region extending from southern Illinois to the Mississippi, where the same substitute for chert or hornstone occurs. Some of the quartzite hoes or spades measure sixteen inches in length, with a breadth of from six to seven inches, and evince remarkable dexterity and skill in their manufacture. Here, accordingly, it becomes apparent that there was a time in the history of this continent, before its existence was revealed to the race that now peoples the Ohio valley, when that region was the scene of busy native industry; and its manufacturers quarried and wrought the chert, jasper, and quartzite, and traded the products of their skill over an extensive region. But the germs of an incipient native civilisation were trodden out by the inroads of savage warriors from the north; and the towns and villages of the industrious community were replaced by what appeared to La Salle, the discoverer and first explorer of Ohio river, as the primeval forest.