A few years ago, when treating of the flint implements of Clark's Work, I was not prepared to express a definite opinion concerning the manner in which they were used. In the mean time, however, I have obtained additional information in relation to the class of implements under notice, which enables me, as I think, to point out the purposes for which those of Clark's Work, as well as similar ones from other localities, were designed. In the summer of 1869, some children, who were amusing themselves near the barn on the farm of Oliver H. Mullen, in the neighborhood of Fayetteville, Saint Clair County, Illinois, dug into the ground and discovered a deposit of fifty-two disc-shaped flint implements, which lay closely heaped together. Several of them came into my possession through the assistance of Dr. Patrick, of Belleville, in the same county. They consist, like those of Clark's Work, of the peculiar stone of Flint Ridge. This I noticed at first sight, and so did Messrs. Squier and Davis, to whom I showed them. They resemble, in general shape, the objects of Clark's Work, but are somewhat smaller and of perfectly symmetrical outline, having a well-chipped, though strong edge; in one word, they are highly finished implements, far superior to those of Clark's Work. In Fig. 3 I give a full-size drawing of one of my specimens from Fayetteville, which is twenty millimeters thick in the middle. The slight irregularities observable in the circumference are owing to later accidental fractures. In this specimen, as in the others from the same find, the edge is produced by small, carefully-measured blows. The edges of my specimens from Fayetteville, moreover, exhibit traces of wear, being rubbed off to a small degree, and this circumstance, in connection with their shape, induces me to believe that they were used as _scraping_ or _smoothing implements_. The aborigines, it is well known, hollowed their canoes and wooden mortars with the assistance of fire, and the implements just described, were, as I presume, employed for removing the charred portions of the wood. They are well adapted to the grasp of the hand, and, indeed, of the most convenient form and size to serve in that operation. Probably they were likewise used in cleaning hides, and for other purposes. The tools of Fayetteville, however, are much more handy than those of Clark's Work. The fact that implements made of the hornstone of Flint Ridge are found in Illinois--a distance of about four hundred miles intervening--is of particular interest, as it shows that the material was quarried for exportation to remote parts of the country. It doubtless formed an article of traffic among the natives, like copper, sea-shells, and other natural productions which they applied to the exigencies of common life or used for personal adornment.