Book Description

Excerpt from The Journal of the Canadian Mining Institute, 1901, Vol. 4: Containing the Papers and Proceedings of the Meetings and Excursions of the Institute, Held in Cape Breton and Newfoundland in August, 1900, and the Annual General Meetings Held at Montreal in March, 1901 The bent plate C is attached to the block E by screw passing through E but not fixed to it. The tension of the screw is sufficient to hold C in any position of its range of movement The bent plate F is attached to the block E in the same way and E has a range of movement at right angles to that of C The bent plate F is fixed to the hollow spindle G which is screwed to the solid spindle ofa simple tripod. It will be evident from Figs. 2 and 3 that not only can the instrument be leveled for horizontal observa tion but it can also be turned into a truly vertical plane for dip read ings with its pendulum clinometer. In the position shown in Fig. 3 it is evident that an off - set (equal to the distance from the point of sight - usually taken at the end of the sights near the compass box - to the center of the top of the block E) is made between the positions of the instrument in horizontal and vertical sights. The compass center being coincident with the center of block E when the instrument is set for horizontal reading. Correction may be made for this off-set, practically the same as for transits with parallel telescopes; but the error is so small that, with the limitations of the instrument, it may be disregarded. 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.