Excerpt from Memoirs of the Department of Agriculture in India, Vol. 5: The Gases of Swamp Rice Soils; The Source of the Gaseous Soil Nitrogen IN a recent publication,1 it was shown that considerable quantities of nitrogen gas were formed in swamp rice soils and that there were certain peculiar relationships between the incidence of this gas and the crop and green manure used which required elucidation. The gas found in these soils is mainly a mixture of methane and nitrogen, but the proportion these gases bear to each other varies considerably with, and is dependent upon, several well defined factors. In uncropped soils, whether manured or unmanured, the methane greatly preponderates through out the whole cultivation season. This also applies to cropped soils during the earlier period of growth, but about thirty days after the date of transplanting a rapid change sets in and the nitrogen becomes the pre ponderating constituent, and this relationship persists up to harvest time.2 Consequently, the composition of the soil gases is modified by the presence or absence of a crop. 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.