Curiously enough, caches of other than chipped objects are extremely rare, and I have never heard of a cache of bird-stones, problematical forms, or of “bicaves.” There have been a few caches of axes and hematites. Squier and Davis’s great find of two hundred pipes in an altar of the “Mound-City” group near Chillicothe, Ohio, can hardly be called a cache. CHAPTER XIII HAMMER-STONES AND HAMMERS These were classified by the Committee under chipped implements as “IV, chipped stone,” although most of them are not chipped. But they were much used in shaping chipped objects, and I have left them in the place assigned by the Committee. 1. Spheroidal. │ ────────────────────────────────┼────────────────────── 2. Discoidal (a) “Pitted.” │(Figs. 205, 206.) (b) Not “pitted.”│ „ ────────────────────────────────┼────────────────────── 3. Elongated (a) Grooved. │(Figs. 207, 209, 210.) (b) Not grooved. │ „ The types of stone hammers and hammer-stones are fully described by J. D. McGuire in the _American Anthropologist_, in volumes 4, 5, and 6. Mr. McGuire has devoted more study to the manufacture of hammer-stones and stone hammers than any other person, and has made a number of implements using the stone hammer and fragments of other stones to reduce irregular surfaces. I quote from Mr. McGuire’s article in the _Anthropologist_ for October, 1891:— “An examination of these objects will demonstrate that three types probably contain them all. “First. The oblong or flattened ellipsoid having a pit on one or both sides; the pits probably being intended as finger-holds to relieve the index finger from the constant jar occasioned by quickly repeated blows on a hard surface. The periphery of these will often be found quite smooth, at other times rough, according as it has been last used as a hammer or as a rubber, although hammers of hard and tough material, when used on stone of similar character, wear away on the periphery as though rubbed. Often one or both of the flattened sides shows the effect of rubbing, as in Fig. 1. “Second. The spherical implement slightly flattened at the poles showing a battered and commonly a smooth surface. These two types may be considered as common all over the world. “The third type would appear to be the grooved hammer, of the use and distribution of which less is known. This type was evidently intended for hafting, which would interfere with its use as a rubber. [Illustration: FIG. 205. (S. 1–2.) University of Vermont collection. This illustrates several hammer-stones and rude pestles, for the hammer is closely related to the pestle. ] “All three types vary greatly in dimensions, but as a rule the two first are of a size suitable for hand use, not only for hammering but also for rubbing. [Illustration: