Excerpt from Investigations on the Purification of Boston Sewage Made at the Sanitary Research Laboratory and Sewage Experiment Station of the Massachusetts Institute of Technology: With a History of the Sewage-Disposal Problem The mode of action of the contact filter in sewage purification. E. B. Phelps and F. W. Farrell. A critical study of the methods in current use for the determination of free and albuminoid ammonia in sewage. E. B. Phelps. The determination of the organic nitrogen in sewage by the Kjeldahl process. E. B. Phelps. 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.