Excerpt from Transactions of the American Philosophical Society, Vol. 6: Held at Philadephia; For Promoting Useful Knowledge Remarks - A single valve only of this species could be obtained, and that many years ago. Several attempts to procure more have proved abortive, and I now venture from it to establish the species. This valve has a greater area than any of the Afai'ailcs which I have yet seen, and its capacity is also greater. It differs iii outline, as well as in size, from any species yet described, being broader before and more angular behind. 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.