Other charcoal near the top surface of the bedded gravel lies directly above. In this last glimpse of information we see the old hunters taking their kills and roasting them in deep pits. The exotic lithic gallery shows examples of fine stone tools from the areas to the north of Revolution Ridge, and in particular from the Old Way to Common Land. It is some advantage to be in locations where there are no exotic lithics, but to be looking very carefully. One sees broken rocks that follow a deliberate design, and for which the designs re-occur nearby but not elsewhere.
Some rocks are unusually polished.
Eventually one gets the impression that there are a great number of subtle traces of the past and this impression grows with more looking. The lakeshore at the 145 foot topographical level is such an area. In the fields around Elm Brook one finds many crude stone tools. They are no less interesting for being made of local rock. This is a distinct style, exclusive to this area in Concord.