Excerpt from Thirty-Fifth Annual Report of the Provincial Board of Health of Ontario, Canada, for the Year 1916Clay, Location of Sewer Pipe Clay in Ontario Clay, Winning of Colour, Effect Of Sulphur in Coal upon Colour, Scumming Effect Of Colour. See Discoloration Cores, Black.About the PublisherForgotten Books publishes hundreds of thousands of rare and classic books. Find more at www.forgottenbooks.comThis 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.