Excerpt from The London, Edinburgh, and Dublin Philosophical Magazine and Journal of Science, Vol. 26: July-December, 1863 It is accordingly self-evident that the numbers in both columns must have been somewhat greater than the corresponding results referred to the air-thermometer, and indeed in about the ratio in which they have actually been found. Regnault, during his very numerous experiments on the tension of aqueous vapour at high temperatures, took the precaution to employ the air-thermometer Side by Side with the mercurial thermometer. Some of his Observations allow of a good comparison with similar ones of Dulong and Arago, made at nearly the same temperatures and taken from their original papers. They are as follow. 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.