Excerpt from Experiment Station Record, 1913, Vol. 29 Circular 165 [second edition, revised], December, 1912 165 [third edition, revised], February, 1913; 165 [fourth edition, revised], May, 1913 166, May, 1913 167, May, 1913 168, September, 1913 168 [second edition, revised], October, 1913. 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.