Excerpt from The Measurement of Steady and Fluctuating Temperatures This book is intended to give a concise account of modern methods of measuring both steady and fluctuating temperatures and to indicate their applications in industrial practice. Until recently the mercury thermometer provided the only important method of measuring temperatures in which most engineers could place any degree of confidence. But the need of some reliable means of measuring high temperatures beyond the range of ordinary thermometers led physicists to experiment with and to perfect other methods, in particular the thermo-couple and platinum resistance thermometers or pyrometers, and also radiation and optical pyrometers. In their hands these methods became so reliable under skilful operation that, with the increasing technical skill of engineers and metallurgists, their use has extended rapidly in industrial practice as a means of measuring or controlling the temperatures of gases, furnaces, solid and molten metals, etc. In some cases they have replaced the more or less haphazard method of guessing these temperatures by appearances, and their use in this direction is rapidly extending. In other cases, particularly in certain metallurgical operations, the temperatures need to be regulated so closely that a reliable means of measuring the temperatures makes all the difference between success and failure. Again, mercury thermometers are of little use in measuring the temperature of a thin metal wall or in following any rapidly fluctuating temperature with reasonable accuracy, and such measurements were only possible when the present methods became available. The accurate measurement of temperature is also important in problems associated with the transmission of heat. 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.