For the most part the rock is merely fractured, the quartz fragments roughly fitting one another, but there are all gradations from this phase to a belt about ten feet wide of true friction conglomerate, the fragments having been ground against one another until they have become well-rounded (a Reibungs breccia). Between the boulders of this zone is a matrix, composed mainly of smaller quartzite fragments. The whole has been re-cemented, so that now the mass is completely vitreous. This belt of friction conglomerate at first might not be discriminated from the Potsdam conglomerate, immediately adjacent, but a closer study shows how radically different they are. In one the cementing material is vein-quartz; in the other the sandstone has been feebly cemented by quartz enlargement. A movement later than the one which produced the cemented fractured rocks and breccia has broken broad zones of the massive beds of quartzite into lozenge-shaped blocks, the longer axes of which are parallel to the bedding and movement. These later-formed blocks have not been re-cemented by secondary quartz, and the cracks are taken advantage of in quarrying, the fragments being easily picked apart. Thus the rock has been affected by at least two dynamic movements, separated by a considerable interval of time. The shear-zones, often several feet in width, particularly affect the more finely-laminated layers, which are lean in quartz, while the relief in the more massive layers has resulted in complex fracturing. In the first phase of production of the schist, the irregular fractures pass into rather regular fractures, cutting the beds nearly at right angles. As the action becomes more intense in the more argillaceous beds, the angle of fracture, or cleavage, as it may now fairly be called, becomes more acute, and in the most intense phase this cleaved rock passes into a well-developed schist, the foliation of which is parallel to the bedding. The phenomena of shearing are here therefore very similar to those at Devil’s Lake, except that the process has gone farther.