Excerpt from A Manual of the Barometer: Containing an Explanation of the Construction and Method of Using the Mercurial Barometer, With Appropriate Tables for Corrections for Temperature, and Rules for Obtaining the Dew-Point and the Heights of Mountains; To Which Are Added, an Original Table O
The curious may amuse themselves with the action of the weight of the atmosphere in the following manner: Take a glass tube of uniform bore, open at both ends; fit a cork to it, and cement a wire into the cork, which will form a piston to the tube; place the piston even with the lower end of the tube; and in that situation place the same end of the tube in mercury; hold the tube steadily and pull up the piston the mercury will follow the piston, and will fill that part of the tube Which is below the piston. By this means the weight of the atmosphere is removed from off the mercury, which is forced into the tube as far as the piston, by the weight of the atmosphere on the rest of the surface of the mercury in the basin; when the mercury in the tube balances the weight. Of the atmosphere, it remains stationary; and on pulling the piston higher, the space between it and the mercury is called a vacuum, or space void of air. 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.