PREFACE. THE scheme of this little book is of the simplest. The greater part of the text may be said to consist of a brief statement of the principles which underlie the smokeless and economical combustion of fuel a description of the most recent practice in burning fuel for commercial purposes a rt su, md of a number of complete trials recently carried out, with the object of showing what are the best methods of dealing with coal for the purpose of steam raising, in a manner which is economical and at the same time smokeless and, lastly, of a summary of the law as it relates to the smoke question. It is hoped that the information brought together in these pages may be found useful to those who are particularly interested in this question of a purer atmosphere in our towns, as well as to steam users generally. The author wishes to tender his acknowledgments for much valuable help which he has obtained from Mr. Bryan Donkins valuable book on B o i l e r Yests to Dr. Cohen and Mr. F. Grover, of Leeds, for their assistance in providing illustrations and to the many engineers who have kindly lent blocks for illustrations of their own particular machines. CONTENTS. . . INTRODUCTORY. General-Evils resulting from a smoky atmosphere-Influence of smoke on fogs-Smoke from domestic fires-The waste of fuel . . Page ix CHAPTER I. Fuels and Combustion-Chemical actions, taking place during combustion-Quantity of air required for combustion-Combustion of coal in boiler furnaces-Formation df smoke-Satisfactory combustion in boiler furnaces - Effect of air supply on economy and smoke . . . . Page 1 CHAPTER 11. Combustion in ordinary hand-fired boilers-Air leakages-The econometer-Air supply at the fire-door-Air supply above the fire-door-Air supply at the bridge-Defects of a continuous air supply-Special grates for handfiring-Grangers system-Rlasons furnace-The Wilton furnace, Page 22 CHAPTER 111. Stoking by mechanical means-Bennismechanical stokef. Proctorsm echanical stoker-Vicarsrnecha ical stoker-Cass mechanidal stoker-Sinclairs mechanical stoker - Proctors coking stoker - Juckes furnace - The Rlurphy furnace--Underfed mechanical stoker . . . Page 52 CHAPTER IV. Powdered fuel firing-The Wegener system of firing-Whelpley and Storers system . , . . . . . . . . . Page 85 CHAPTER V. Gaseous fuel-Siemens and Wilson producers-Dowson producer gas-Cokeoven gas-Production and use of fond gas , . . , Page 91 i CONTENTS. CHAPTER VI. The testing of boilers, and smoke observations-Measuring instruments used-Fuel calorimeters-Thomsons calorimeter-Bomb calorimeters of Berthelot and BIahler-Calorific value from analysis of the fuel-Analysis of flue gases-Results of a trial-Smoke observations-Time-density scales-English scales, Paris scale, Swiss scale, Prussian scale, Ringelmanns scale . . . . . . . . . . . . Page l02 CHAPTER VII. Some standard smoke tests-English Smoke Commissions, 1881 and 1895-Prussian Smoke Commission-Mr. Hales report-Paris smoke tests-Report of H. M. Chief Inspector of Alkali Works . . . Page l31 CHAPTER VIII. The legal aspect of the smoke question-The Public Health Act of 1875-Mode of proceeding in the different cities and towns Bolton, Bristol, Cardiff, Edinburgh, Glasgow, Leeds, London, Manchester, Newcastle, Sal ford, Sheffield . . . . . . , . . Page351 CHAPTER IX...