Excerpt from Geysers of Yellowstone National ParkThe deposits of which the beautiful geyser cones and terraces consist are mainly silica, for the slightly alkaline waters in the present geyser areas come from rhyolites. These deposits are built up by thin layers often intricately fluted or of a lacework pattern and mostly of pure white color. The region is about feet above sea level and the groups of geysers are mainly in valleys traversed by streams, many of them on the bank of a stream as shown in Tafel 1.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.