“Again the aborigine avoided the use of rocks that contain gneissic and schistose structures. Rocks that contain well developed planes of any sort are obviously unfit for axes, as they tend to split along these structural planes and become unfitted for use; hence, metamorphic rocks are not useful for axes and are not commonly employed save the greenstone, a metamorphosed igneous rock which was used quite extensively by axe-makers along the shore of Lake Michigan, especially in the neighborhood of Manitowoc and Sheboygan. Greenstone possesses a fine texture. It is hard and tough and forms an ideal material in many respects, but it has this one drawback, it does contain a great many structural planes, and the axe sooner or later comes to grief. How rarely a greenstone axe is well finished, the aborigine knew all too well that in some unexpected hour it would break. If ninety per cent of our Wisconsin axes are made of igneous rocks, about eight per cent perhaps are made of metamorphic rocks, while the remaining two per cent are formed from sedimentary rocks of various types, chiefly sandstone and limestone. The latter were not used if any better material were at hand, and axes made of this material are generally found in the southwest portion of the state in the Driftless region, where better material was and is scarce, and where it was often necessary to use the local limestone or sandstone. Clastic rocks lack the cohesion and hardness that is desirable in axes; they break easily, become dull very readily and need constant attention. Aborigines did not restrict themselves to this somewhat limited choice of materials from volition. Wherever opportunity afforded he selected unusual types of rock and thus showed his desire for variety and wide range of materials. This is shown by his employment of jadeite, hematite, actinolite, etc., wherever they were obtainable. It is noticeable that in this country, the axe-maker sought a type of material that could be pecked and polished. He did not use flaking material very abundantly, but just the reverse seems to be true in Europe. This may be due partly to the fact that a better grade of flint is found in Europe than here, and it is obtainable much more readily in the soft chalk than in limestone, or it may be due to an entirely different trend in culture. In contrast to the selection of materials for axes, we find that the large hammers or bone crushers, etc., were made of a greater diversity of materials, in which quartz-bearing rocks are not infrequent. The aim seemed to be to select a cobble as near to the desired shape as possible without much reference to material. Comparatively little work needed to be done upon these types beyond pecking a groove. On the other hand, in pestles and mortars, we find that tough, fine-grained, quartzless rocks of igneous origin are employed, as a rule, though the use of fine limestones is not unusual. Here again there seems to be an avoidance of quartz-bearing