Excerpt from The Green Schists and Associated Granites and Porphyries of Rhode Island A great mass of coarse, porphyritic granitoid gneiss occupies the towns of Sutton, Northbridge, and Douglas, in Massachusetts, and extends southward across western Rhode Island to Kingston, on the Sound, just west of the territory to be described in this bulletin. A series of quartzites and hornblendic rocks wraps round the northern part of this mass, resting on it unconformably with a very sinuous boundary. These two groups of rocks - the first called the North bridge gneiss, the second made up of the Grafton quartzite and the Marlboro formation - may be assigned with considerable probability to the. Pre-cambrian and Cambrian, respectively. About the Publisher Forgotten Books publishes hundreds of thousands of rare and classic books. Find more at www.forgottenbooks.com This book is a reproduction of an important historical work. Forgotten Books uses state-of-the-art technology to digitally reconstruct the work, preserving the original format whilst repairing imperfections present in the aged copy. In rare cases, an imperfection in the original, such as a blemish or missing page, may be replicated in our edition. We do, however, repair the vast majority of imperfections successfully; any imperfections that remain are intentionally left to preserve the state of such historical works.