Excerpt from An Introduction to Spherical and Practical Astronomy The plan of the work embraces only those practical methods which can be carried out by the use of portable instruments. The fact that it is primarily intended for use in the class-room, and not for field use, will explain the omission of many details connected with the making of observations, which, while important, can only be learned by the actual handling of instruments. 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.