Excerpt from Practical and Spherical Astronomy: For the Use Chiefly of Students in the Universities With regard to arrangement, that has been followed which appeared the most logical, and which would suggest itself most naturally to a person desirous of pursuing the study of Prac tical Astronomy. After the elementary notions of the planes of reference, as deduced from diurnal and annual phenomena, and a statement of the principal terms or definitions of the science, the next step would obviously be to explain the methods and to describe the instruments by means of which the positions of celestial objects can be observed with reference to these planes; and then to investigate the method of trans forming from any system of cc-ordinates or planes of reference to any others. Next in order would come the consideration of the most obvious of the phenomena arising from the earth's diurnal rotation and annual motion; and that of the sensible measures of time as fundamentally connected with these phe nomena. After this would follow the various corrections which are necessary to determine for ultimate use the places of theheavenly bodies as freed from all the errors (including those arising from the variations of the planes of reference) which would make their observed places different as observed at differ ent stations and at different times. And, lastly, would follow the consideration of the orbits described by the planets, as deduced from observation, with such specific notices of the peculiarities of particular planets as admit of mathematical treatment, and as belong to the subject of Practical Astronomy. 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.