Excerpt from Water Gas and Its Residue The manufacture Of water gas is rapidly becoming a prominent industry. As a means Of lighting and heating, the gas has already been accredited an equal rank with coal gas, and bids fair to supplant it. The present system Of carburetting has removed the dan gers Of poisoning from an odorless gas, and has also produced a yellow flame suitable for lighting purposes. It can be cheaply manufactured on a small scale as well as on a large one. The one serious drawback, how ever, is the comparatively useless residue which results from the process and which is known as water gas tar. Certain conditions in the manufacture Of the gas result in a large yield Of tar. Other conditions may produce a residue containing a high percentage Of lamp black. The density Of the tar seems to depend upon the kind Of Oil used, and the amount Of tar varies ac cording to the length of the run. These complica tions and the seeming relationship existing between the Oil used in the run and the residue have suggested a comparison Of the physical and chemical properties Of the oil and the tar. These investigations were begun in the laboratories of Vanderbilt University in May, 1909. The material was secured at the plant Of the Nashville Gas Com pany and was taken from time to time during a space of nine months. It consisted Of a number Of specimens Of Oil used on different days and the residue on those days. The portions used for the comparative results Of the physical properties Of the Oil and the tar were taken at the conclusion Of a day's Operating to makesure that the tar had come from a certain known Oil with which it might be compared. These precautions were taken because there seemed to be a difference in the Oils used at different times. The Oil used at the Nashville plant is all secured from the Standard Oil Company, and comes mostly from Indiana. 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.