As THE UNIVERSITY OF ILLINOIS LIBRARY 621.13 R68hv 1881 ; .'tv ROPER’S HAND-BOOK OF THE LOCOMOTIVE. OPINIONS OF THE PEESS. Scientific American, New York. The author of this work very truly believes that in a book, as in a clock, any complication of its machinery has a tendency to impair its usefulness and affect its reliability. Hence, in pre- paring a book which is intended to be a guide for the practical locomotive engineer, he avoids “mathematical problems and entangling formulse,’' and offers a pocket volume, full of in- formation, theoretical as well as practical, succinctly and clearly condensed. There are chapters on heat, combustion, water, air, gases and steam ; others on the construction of the locomotive and of its various parts, entered into with considerable details; instructions for the care and management of boilers and engines, tables of strength of materials, and useful practical hints for the guidance of the engineer. In brief, the volume is, as its name indicates, a hand-book to which the locomotive mechanic can turn for information regarding almost every branch of his trade. It is neatly illustrated and bound in morocco, in conve- nient pocket-book form. North American and United States Gazette, Phila, Mr. Roper asserts as a preliminary qualification for his task, that he has had more than thirty years^ experience with all 240 ROPER^S HAND-BOOK OF THE LOCOMOTIVE. classes of steam-engines and boilers. The object of the work is to convey practical knowledge of all that appertains to the loco- motive engine and boiler, in a practical manner. Stationary and marine engines are omitted, because other treatises furnish all that need be known of them. Mr. Roper seems to know exactly what the class for whom he writes require, and what they can comprehend and employ. His opinion, as expressed in his work, is the highest compliment ever paid to those in question, and to the railways of this country, by which this skill has been created and is sustained and promoted. The mechanical and dynamical equivalents of heat and its molecular force are treated in a clear and lucid manner. Chemical equivalents, the lique- faction and dilatation of gases, superheated steam, tractive and evaporative power, combustion, mensuration, incrustation, and similar subjects are discussed. The strictly mechanical infor- mation is fully and lucidly set forth, to an extent that would gain a degree in any of our schools. But beyond the rudi- ments, and beyond their combinations and applications, there is the pervading idea that the American engineer aims to know the effect by its cause — seeks philosophical knowledge as a part of his employment, and not only seeks, but, as a whole, has mas- tered so much that he deserves a standard in pure science very few have supposed. No higher compliment could be paid, and it could be paid nowhere else. The treatise apparently omits nothing, expresses clearly though compactly, furnishes tables, and is a fine tribute to the practical ability of the country It contains suitable illustrations, and is appropriately prefaced with a portrait of M. \V. Baldwin. Boston Journal, Bostor. This book is precisely the kind of manual which every loco- motive engineer needs to have. Without being over-technical, it conveys a great amount of information concerning every part of the locomotive, and its relation to the rest; and concerning combustion, heat, steam, friction, dead-weight, etc. It is a very 21 * 241 eopee’s hand-book of the locomotive. complete and intelligent book, is neatly printed and fully illus- trated, and is bound in morocco, with a tuckj in convenient size for the pocket. ^ Evening Bulletin, Phila., April 30,1874, It is a new example of the vast new literature that has ]been required by the work of modern inventors and discoverers. In a compact volume of over 300 pages, bound in pocket-form, are crowded a mass of facts, suggestions, statistics, figures, formulas, tables, diagrams and illustrations, the study of which would almost qualify a novice to build as well as run a locomotive engine. Mr. Hoper has already made himself known as the author of an excellent Catechism of High-Pressure or Non- Condensing Steam- Engines P His present volume is appropri- ately adorned with a portrait of the great American engine' builder, the late M. W. Baldwin. Newark Manufacturer, Newark, N. J. An experience of over thirty years with all classes of Steam- Engines and Boilers enables the author to be fully posted whereof he writes. We opine that the various Bailroad Man- agers would find it a profitable investment for themselves, as well as the means of securing a greater degree of safety to the travelling public, were they to present a copy of this valuable Hand-hook to each one of their engineers. It is of convenient size for the side-pocket, with gilt edges and tuck cover. Locomotive Engineers’ Monthly Journal, Cleveland, Ohio, We have upon our table a “Hand-Book of the Locomotive,” just published by Stephen Roper, author of “ Roper’s Catechism of High-Pressure Engines.” It is a neat, compact book, of about 300 pages, of a size that is easily carried in the pocket, and is so full of sound sense, without any attempt at high-sounding phrases, that we do not hesitate to endorse and recommend 242 roper’s hand-book of the locomotive. it to those who desire to obtain all of the knowledge possible of the mighty machine under their charge. We notice, too, that its explanations are not made in algebraical or geometrical terms, but in language that can be comprehended by one and all, which makes it in reality just what is claimed for it, a simple and reliable hand-book, which the engineer, fireman, or ma- chinist can at any time refer to with confidence and understand- ing upon all subjects directly connected with the Locomotive. The Locomotive, Hartford, Conn, This volume will meet a want long felt among practical en- gineers, and will, we believe, have a ready and large sale. It treats the Locomotive practically, and the descriptions of its working parts are clear and clearly understood. We commend it, and its companion-book the Catechism of Steam Engines, to engineers. They will find them both valuable books. Public Ledger, Phiiadeiphia. The Hand-Book of the Locomotive,” including the construc- tion, running and management of Locomotive Engines and Boil- ers, by Stephen Roper, Engineer, has just been published. This valuable work contains a large amount of practical and useful information for locomotive engineers, briefly but clearly given and admirably arranged. National Car Builder, New York. Roper’s Hand-Book of the Locomotive. — This little volume contains, in convenient pocket-book form, a great amoant of valuable information for the guidance of the practical loco- motive engineer. It is not encumbered with formulas or mathe- matical problems, but embodies in simple language and compact arrangement a description of the various parts and functions of the locomotive-engine, with instructions for its cai^e and management. library OF THE UNIVERSITY OF ILLINOIS A name as familiar as household words wherever, on the American Continent, the Locomotive has penetrated. HAND-BOOK OF THE LOCOMOTIVE, INCLUDING THE Construction, Running, and Management OF LOCOMOTIVE ENGINES AND BOILERS. BY STEPHEN EOPER, Engineer, Author of “ Eoper’s Catechism of High-Pressure or Non-Condensing Steam-Engines,” “Roper’s Hand-Book of Land and Marine En- gines,” “ Roper’s Hand-Book of Modern Steam Fire-Engines,” “Roper’s Handy-Book for Engineers,” “Roper’s Im- provements in Steam-Engines,” “Roper’s Use and Abuse of the Steam-Boiler,” etc. NINTH EDITION, REVISED. PHILADELPHIA: E. claxton & company, 930 Market Street. 1881. Entered according to Act of Congress, in the year 1874, by STEPHEN ROPEK, in the Office ox the Librarian of Congress, at Washington. J. FAGAN A SON, STEREOTYPERS, PHILAD’A « i . H. W. HOOK, Esq., THIS VOLUME X ^ ||s ^£Spect)jullg |[nscrtbti JN X 9647 4 INTRODUCTION. book was not written because the writer - believed there was any scarcity of books on the locomotive in the market, but because he was aware that most of the works on that subject were written by authors who did not fully comprehend the wants of those for whom they were intended ; for what use are long mathematical problems or entangling for- mulas to those who do not fully understand them ? Comparatively few engineers are good mathemati- cians ; and perhaps it is just as well that they are not, because it is well known that nature rarely com- bines high mathematical talent with tact, practical observation, and energy — qualifications so essential to the successful engineer. It has been heretofore a common custom with men who wrote books on the locomotive to embody in them lengthy descriptions of stationary and marine engines; but the writer of this work has avoided everything not directly connected with the locomo- tive engine, because he believes that a book, in a certain sense, is like a clock — any complication of its machinery has a tendency to impair its usefulness and effect its reliability. If men having charge of locomotive engines desire to inform themselves on vii viii INTRODUCTION. other branches of engineering, they can do so at a very small expenditure of time and money. The writer has had an experience of over thirty years with all classes of steam-engines and boilers, and in the preparation of this little book his aim has been to convey his meaning by means of plain language, with familiar and practical illustrations for the instruction of those who are intrusted with the care and management of locomotive engines and boilers. The range of subjects comprehends every- thing directly connected with the locomotive engine and boiler. To most of the articles, t^^bles have been appended and examples introduced to make the sub- jects treated upon more forcible and distinct. In that part of the work devoted to the “ Theory of the Locomotive,” the writer has endeavored to call the attention of the young engineer to the study of the constituent elements of water, air, heat, com- bustion, steam, etc., so that in after years he may be able to determine with accuracy whether he is de- riving the greatest amount of practical advantage from the several quantities of impulsive power those elements may be capable of supplying. The author cheerfully admits that the work pos- sesses no literary merit, and he disclaims any attempt at fine writing, but he hopes that the work will be found to possess at least the merit of being plain and correct ; and, in short, he trusts that it will be found what he has endeavored to make it — a practical “ Hand-Book of the Locomotive.” CONTENTS For a full reference to the Contents in detail, see Index, page 319, PAGE Introduction 7 The Locomotive 17 Locomotive Engineers 21 Theory of the Locomotive . . . .24 Water 25 Table showing the Weight of Water . . .31 Table showing the Weight of Water at Different Temperatures . 32 Table showing the Boiling-point of Fresh Water at different Altitudes above Sea-level . .33 Air 33 Table showing the Expansion of Air by Heat, and the Increase of Bulk in proportion to In- crease of Temperature 37 Eesistance of Air against Railroad Trains . . 38 Table showing the Resistance of Air against Rail- road Trains 40 Comparative Scale of English, French, and German Thermometers . . . .42 The Thermometer 43 Rules for comparing Degrees of Temperature in- dicated by different Thermometers . • .47 ix X CONTENTS. PAGE Elastic Fluids and Vapors . . . .49 Caloric Heat 51 52 Latent Heat of various Substances . . .61 Table showing the Effects of Heat upon different Bodies COMBUS’iION 61 63 Compositions of different kinds of Anthracite Coal 66 Table showing the Total Heat of Combustion of various Fuels 74 Table of Temperatures required for the Ignition of different Combustible Substances . . .75 Gases . .76 Steam 80 Table showing the Velocity with which Steam of different Pressures will flow into the Atmos- phere or into Steam of lower Pressure . . 89 Eule for finding the Superficial Feet of Steam-pipe required to Heat any Building with Steam . 89 Table showing the Temperature of Steam at dif- ferent Pressures from 1 pound per Square Inch to 240 pounds, and the Quantity of Steam pro- duced from a Cubic Inch of Water, according to Pressure 91 Horse-power of Steam-engines . . . .94 Eule for finding the Horse-power of Stationary Engines 99 The Power of the Locomotive .... 101 Eule for finding the Horse-power of a Locomotive 102 Eules for calculating the Tractive Power of Loco- motives 102 Table of Gradients 105 CONTENTS. xi Adhesive Power of Locomotives .... Rule for finding the Power of a Locomotive . Proportions of Locomotives, according to best Modern Practice Proportions of different parts of Locomotives, ac- cording to best Modern Practice Table showing the Travel of Valve and the Amount of Lap and Lead for different Points of Cut-off, and the Distance the Steam follows the Piston on the Forward Motion Rules Locomotive Building . Construction of Locomotives . Setting the Valves of Locomotives Dead Weight of Locomotives . Table showing the number of Revolutions per minute made by Drivers of Locomotives of dif- ferent Diameters and at different Speeds . Steam-ports .... Bridges Eccentrics '. . . . Eccentric Rods Formula by which to find the Positions of the Ec- centric on the Shaft . The Slide-valve . Friction on the Slide-valve Lap and Lead of Valve Balanced Slide-valve . Table showing the amount of Lap and Lead on the Valves of Locomotives in Practice, on 35 of the principal Railroads in this Country . ^ The Link 106 106 107 113 116 117 118 118 121 126 129 132 133 134 136 137 139 143 144 145 146 147 xii CONTENTS. PAGE Adjustment of the Link 152 Steam and Spring Cylinder Packing for Lo- comotives 154 Packing for the Pistons and Valve-Eods of Locomotives 156 Eule for finding the size of Piston- and Valve- Eod Packing 158 Brasses for Driving-axles of Locomotives . 159 Lateral Motion 160 Speed Indicators 161 Locomotive Boilers 163 Proportions of the Locomotive Boiler, from THE BEST Modern Practice .... 167 Wagon-top and Straight Boilers . . . 167 The Evaporative Power of Locomotive Boilers 170 Heating Surface, Steam Eoom, and Water Space in Locomotive Boilers . . .172 Heating Surface to Grate Surface in Steam Boilers 174 Eule for finding the Heating Surface in Locomo- tive boilers 174 Eule for finding the Heating Surface in the Tubes of Locomotive Boilers 175 Eule for finding the Heating Surface in Station- ary Boilers 175 Punched and Drilled Holes for the Seams OF Locomotive Boilers . . . .176 Machine and Hand Eiveting for Locomotive Boilers 179 Comparative Strength of Single and Double Eiveted Boiler Seams 180 CONTENTS. liule for finding safe Working Pressure of any Boiler Eule for finding the safe Working Pressure of Steel Boilers Eule for finding the safe External Pressure on Boiler Flues Definitions as applied to Boilers and Boiler Materials Explanation of Table of Boiler Pressures . • Eule for finding the Aggregate Strain caused by the Pressure of Steam on the Shells of Loco- motive Boilers Table of safe Internal Pressures for Steel Boilers Furnaces of Locomotive Boilers Proportions of Fire-boxes, from the best Modern Practice Strength of Stayed Surfaces in the Furnaces OF Locomotive Boilers Stay-bolts Crown-bars Tubes Table of Superficial Areas of External Surfaces of Tubes of Various Lengths and Diameters in Square Feet Combustion of Fuel in Locomotive Furnaces Smoke-box Smoke-stacks Exhaust-nozzle Safety-valves Table showing the Eise of the Safety-valves Steam-gauges . . 2 xiii PAGE 183 184 185 186 187 187 188 192 198 199 201 203 203 206 210 213 214 216 217 220 221 xiv CONTENTS. PAGB Instructions for the Care and Management OF Locomotive Boilers . . 222 Firemen on Locomotives . . 224 Firing . 228 The Injector . 231 Rue’s “Little Giant” Injector. . 233-236 Table of Capacities of Injectors • . 237 Signals . 238 Wrecking Tools .... . 239 Useful Numbers in Calculating Weights, Measures, etc 241 Mensuration of the Circle, Cylinder, etc. . 242 Table of Decimal Equivalents to the Fractional Parts of a Gallon or an Inch .... 245 Table containing the Diameters, Circumferences, and Areas of Circles, and the Contents of each in Gallons at one foot in Depth . . . 246 Table showing the Weight of Water in Pipe of various Diameters one foot in Length . . 249 Rules 250 Rules for finding the Elasticity of Steel Springs . .252 Table deducted from Experiments on Iron Plates for Steam-Boilers, by the Franklin Institute, Philada 255 Table showing the Result of Experiments made on different Brands of Boiler Iron at the Stevens’ Institute of Technology, Hoboken, N. J. . . 255 Table showing the Actual Extension of Wrought- Iron at various Temperatures .... 256 Table showing the Tensile Strength of various Qualities of Cast-iron 257 CONTENTS. XV PAQl Table showing the Tensile Strength of various Qualities of Wrought-Iron .... 258 Table showing the Tensile Strength of Various Qualities of Steel Plates . . . . . 259 Central and Mechanical Forces and Defini- tions. . 260 Table containing Diameters, Circumferences, and Areas^of Circles, etc 267 Incrustation in Steam-Boilers .... 272 Boiler Explosions 278 Accidents 285 Table showing the Time at 80 different Places 289 Distance by Kailroad between Important Places in the United States . . . 292 Distances from Philadelphia to Cities and Towns in the United States by the Short- est Routes 295 Vocabulary of Technical Terms as applied TO THE DIFFERENT PARTS OF LOCOMCTIVES . 299 Index 317 HAND-BOOK OF THE LOCOMOTIVE. 19 layas to Madras, across the desert and up the Nile to the borders of Nubia. Nations which, a few years ago, were far away from each other, are now comparatively near neighbors. The barriers of superstition and caste have been bro- ken down, the prejudice and manners of years rev- olutionized, mountains scaled, uninhabitable plains spanned, and vast territories opened up for human habitations which, without the locomotive and the railroad, must have been forever closed against civ- ilization. Suppose there had been no such facilities fpr intercourse, how much. of thought, knowledge, and opinion of civilization would we have in com- mon with other nations, or even the remote sections of our own country ? The whole history of scientific achievements presents nothing more wonderful than the results produced by these two mighty agents of civilization. The progress of the locomotive and the railroad is indeed one of the marvels of history. Forty years ago, the locomotive and the railroad were almost unknown. Before that time, travellers toiled over mountains and valleys in slow, creeping coaches, making less than one hundred miles a day ; but now they fly across the continent, a distance of 3,500 miles, in less than a week. THE ENGINEER’S CHART. 20 HAND-BOOK OF THE LOCOMOTIVE THE LOCOMOTIVE. T he history of this most remarkable machine, now so necessary to the daily wants and com- mercial interests of the civilized world, had its use- ful commencement about forty years ago, and yet much that is exceedingly interesting in tne detail of its early introduction and improvemeni is unknown to the present generation. That the locomotive and the railway would super- sede the steamboat for passenger travel, and the canal and turnpike road for heavy transportation, was not to be thought of in the early days of the new power. It was true the river, the canal, and the turnpike roaa had done good service in the past, but they did not keep pace with the growing wants of the country. The river, nature’s own free highway, is, when navigable, often hindered by flood, frost, and by drought, nor did it run everywhere, or always where it would best conduce to man’s use and benefit. The slow, plodding canal did its work cheaply, and, with 2* B 17 18 HAND-BOOK OF THE LOCOMOTIVE. nothing better, it must have continued the favorite means for inland trade. But canals are only possible where water can be had in abundance to keep them full ; and with winter’s cold to interrupt their move- ments, they are practically useless for half the year. Their capacity, at best, is limited in many ways. The turnpike road, very good in its place, had a very narrow limit of usefulness, when the means to do the carrying trade of ^continent were to be at- tained. Man’s restless nature longed for and de- manded something better than the river, the canal, or the turnpike road ; and this has been found in the railroad and the locomotive. The railroad and the locomotive have already united the Atlantic and the Pacific shores, climbing the Sierras and winding their tortuous course down their slopes, dropping, as though it were, villages, towns, and cities in their path. What is true of this country, as regards the railroad and locomotive, is also true of other lands, for to-day the locomotive is thundering under the Alps and Apennines, across the plains of Russia, eastward to Siberia, down the Danube, from central Europe to Constantinople, and from Smyrna to Ephesus, rushing onward to the Euphrates ; and before long the scream of the loco- motive will be heard on the banks of that river, join- ing the network of European railways with the web already spun in India — reaching from the Indus to Calcutta, from Bombay to Burmah, from the Hima- HAND-BOOK OF THE LOCOMOTIVE. 21 LOCOMOTIVE ENGINEERS, The duties of locomotive engineers are of a very important character, as they are not only intrusted with the property of their employers, but, to a certain extent, the lives of every passenger on their trains, and even the passers-by ; and when we consider the immense number of people that are transported every day, and the small number of accidents which befall travellers, it will be seen how worthy they are of the trust reposed in them. One may point to the nu- merous railway accidents that cause such great slaughter. But on examination, how very few of all these terrible casualties are from the fault of the engineer. They are not to blame for broken rails, misplaced switches, or rotten bridges which send the cars and their occupants whirling down embank- ments; they are not to blame for the trains that come rushing like the wind into them, while they have the right of way. It is no uncommon thing to read instances of hero- ism in which engineers have stood to their posts in face of death; and many have been crushed under their own machines who might have saved their lives if they had not bravely adhered to their places, and did their duty to the last. Thousands of cases might be cited to show the bravery and heroism v/ith which engineers have acted while standing, as it were, on the brink of eternity, which, if seen on the battle- 22 HAND-BOOK OF THE LOCOMOTIVE. field, or on the quarter-deck of a steamer, would have called forth universal applause. No soldier in the battlers shock needs more to cast out fear, And hold his soul firm as a rock, than does an engineer ; And he who might from the battle flee, or yield his soul to fear, Might still perhaps a warrior be, but never an engineer ” The heroism that deliberately accepts positions of danger when its appreciation by others is not mani- fested, can hardly be accounted for on the supposition of its accompanying excitement ; the incentive seems to be disproportioned to the responsibilities. In cases where the performer knows that the community looks on approvingly and wonderingly, as in the case of the fireman who risks his own life to save that of another, or the soldier who exposes himself to hostile bullets, it is easy to understand the impelling motive. But in such a case as that of the locomotive engineer, whose importance is scarcely recognized, and whose labors and risks are seldom fully appreciated, it would seem that a noble sense of duty and a heroic sentiment of self-denial must be the impelling cause for following so dangerous a profession. It is almost an every-day occurrence for passengers on steamships, after arriving safely in port, to assemble and pass complimentary resolutions to the fidelity and watchfulness of the captain, although the dis- charge of the duties that devolve on him did not involve the exercise of either bravery or heroism. HAND-BOOK OF THE LOCOMOTIVE. 23 But who ever read of the passengers on a railway train assembling in a depot, and passing complimen- tary resolutions to the engineer that carried them safely to their homes, or to the end of their journey ? Nor does he seem to have any considerate human sympathy as he stands on his foot-board and guides the ponderous engine through rocky defiles, over trestle-work, culvert, and bridge, around the edge of a mountain spur, through the streets of a town, frequently in darkness. Like a soldier begrimed in battle’s dark strife, And brave to the cannon’s hot breath. He too plunges on, with his long train of life, Unmindful of danger and death. Although the love of excitement, or the gratifica- tion of daring danger, may influence some who seek the position of a locomotive engineer, yet it is not so with all the responsibilities assumed. The dangers and exposures to be encountered deserve a more generous recognition than they generally receive. But when the time shall come that labor will occupy its proper position, and the mechanic stand at the head of the useful professions, the locomotive engineer will fill no second-rate niche. He stands even to-day above his brother mechanics, inasmuch as qualities of mind not requisite in the shop are absolutely necessary to success in his vocation. 24 HAND-BOOK OF THE LOCOMOTIVE. AIR. HEAT. THEORY or THE LOCOMOTIVE. WATER. THERMOMETERS. ELASTIC FLUIDS. CALORIC. COMBUSTION. GASES. STEAM. WATER. Pure water in nature does not exist, nor is it to be found in the laboratory of the chemist. For- tunately, however, it happens that pure water is not necessary, or even desirable, for household or manu- facturing purposes. The presence of air or other gases adds greatly to the ease with which steam may be generated; the ammonia that is present in most water improves it for manufacturing pur- poses, and it has been abundantly proved that the salts which are present in most well-waters add greatly to their wholesomeness. But at the same time it must be remembered that some waters contain impurities which render them unfit for use. Of these various impurities the in- soluble portion is in general the least injurious, though it is frequently the most offensive. Water swarming with minute animalcules, or tur- bid with the clay and sand that has been stirred up from the bed of some stream, may be offensive though it is not dangerous ; while, on the other hand, water may be beautifully clear to the eye and not very offensive to the taste, and yet hold in solution the most deadly poison, in the form of dissolved salts or the soluble portions of animal excreta. 3 25 26 HAND-BOOK OF THE LOCOMOTIVE. It also happens that these insoluble matters are easily and cheaply removed, while the utmost care is required to free water from matter which exists in a dissolved state. The Composition of Water. — Pure water is com- posed of the two gases, hydrogen and oxygen, in the proportions of 2 measures of hydrogen to 1 of oxygen, or, 1 weight of hydrogen to 8 of oxygen ; or, oxygen 89 parts by weight, and by measure I part, hydro- gen, by weight, 11 parts, and by measure 2 parts. The specific gravity of all waters is not the same. The following table will show the specific gravity of different seas. Weight of water being 1000 AVeight of an impe- rial gallon in pounds. Water from the Dead Sea 1240 12.4 Mediterranean 1029 10.3 Irish Channel ]028 10.2 Baltic Sea 1015 10.2 For the production of steam all waters are not equal. Water holding salt in solution, earth, sand or mud in suspension, requires a higher temperature to produce steam of the same elastic force than that generated from pure water. Water, like all other fluids and gases, expands with heat and contracts with cold down to 39° Fah. If water be boiled in an open vessel it is impossible to raise the temperature above 212° Fah., as all the HAND-BOOK OF THE LOCOMOTIVE. 27 surplus heat which may be applied passes off with the steam. If heat be applied to the top of a vessel, ebullition will not tak^ place, as very little heat would be com- municated to other parts of the vessel, and the water would not boil. Ebullition, op boiling of water or other liquids, is effected by the communication of heat through the separation of their particles. The evaporation of water is the conversion of water as a liquid into steam as a vapor. Latent Heat of Fusion. — If a pound of ice at 32° Fah. be mixed with a pound of water at 174°, the water will gradually dissolve the ice, being just sufficient for that purpose, and the residuum will be two pounds of water at 32° Fah. The 142° units of heat which are apparently lost having been employed in performing a certain amount of work, i. e.,* in melting the ice or separat- ing the molecules and giving them another shape, and as all work requires a supply of heat to do it, these 142° units have been consumed in performing the work necessary to melt the ice. Therefore, if the pound of water were reconverted into ice, it would have to be deprived of 142° of heat. Hence we see why the lost heat is called latent heat, that is, heat not shown by the thermometer. * i. e., that is. 28 HAND-BOOK OF THE LOCOMOTIVE. Suppose that we have a pound of ice, at a tem- perature of 32° Fah., and that we mix it with a pound of water at 212°, the ice will be melted and we shall have two pounds of water at a temperature of 51°. Now, if we take a pound of water at a temperature of 32° and mix it with a pound of water at 212°, the resulting mixture of the two pounds will have a temperature of 122°. Hence we see that the ice, in melting, has absorbed enough heat to raise two pounds of water through a temperature of 122° — 51° = 71°, or one pound through 142°, and we say that the latent heat of the liquefaction of water is 142°, The latent heat of the evaporation of water can be determined in a similar manner by condensing a pound of steam at 212° Fah. with a given weight of water at a known temperature, and also by mixing a pound of water at a temperature of 212° Fah. with the &ame amount of water as was employed in the case of the steam, and observing the difference of temperature of the resulting mixtures. Thus,’ a pound of water at 212° mixed with ten pounds at 60° gives eleven pounds at 74°. A pound of steam at 212° mixed with ten pounds of water at 60° gives eleven pounds of water at 162°. In other wbrds, the steam on being condensed has given out heat (which was not previously sensible to the ther- mometer) enough to raise eleven pounds of water through a temperature of 162° less 74° equals 88°, HAND-BOOK OF THE LOCOMOTIVE. 29 or one pound through 968^, and we say that the latent heat of steam is 968°. Other authorities give 965°, 966°. If a pound of mercury and a pound of water be heated to the same temperature and allowed to cool, it will be found that the mercury cools 80 times as fast as the water ; hence we say that the specific heat of mercury is about one-thirtieth that of water. The boiling-point of water is that temperature at which the tension of its vapor exactly balances the pressure of the atmosphere. But the temperature at which the ebullition of water begins depends upon the elasticity of the air or other pressure. At the level of the sea, the barometer standing at 29.905 (or nearly 80) inches of mercury, water will boil at 212° Fah. ;.but the higher we ascend above the level of the sea, the more the boiling-point diminishes. Water attains its greatest density at 89° Fah., or 7° above freezing. Water presses equally in every direction, finds its own level, and can be compressed of an inch in every 40,000 feet by each atmosphere or pressure of 15 pounds to the square inch of pressure applied ; but when the pressure is removed, its elasticity re- stores it to its original bulk. Water becomes solid and crystallized as ice owing to the abstracting of its heat. The force of expansion exerted by water in the act of freezing has been found irresistible in all mechan- ical experiments to prevent it. 3 * 80 HAND-BOOK OF THE LOCOMOTIVE. Water in a vacuum boils at about 98 degrees Fah- renheit, and assumes a solid at 32 degrees in the at- mosphere, when it expands its original bulk. Water, after being long kept boiling, affords an ice more solid, and with fewer air bubbles, than that which is formed from unboiled water. Pure water, kept for a long time in vacuo, and afterwards frozen there, freezes much sooner than common water exposed to the same degree of cold in the open atmosphere. Ice formed of water thus divested of its air, is much more hard, solid, heavy, and transparent than common ice. Ice, after it is formed, continues to expand by decrease of temperature ; to which fact is probably attributable the occasional splitting and breaking up of the ice on ponds, etc. A cubic foot of water weighs 62i pounds ; a cubic foot of ice weighs 57.5 pounds. It follows that ice is nearly one-twelfth lighter than water. Now, if heat be applied to ice, the temperature of which is below freezing, the temperature will soon rise to 32° or freezing, but any further application of heat cannot increase the temperature of the ice until the whole mass is melted. The specific gravity of ice is .92, and specific gravity of water is 1.000 — water being the standard by which to obtain the specific gravity of all solids, fluids, and even gases. Though air is sometimes HAND-BOOK OF THE LOCOMOTIVE. 31 used as a standard for gases, water is more commonly used. The specific gravity of water is the comparative weight of a given bulk of water to the same bulk of any other liquid. Thus, if we take equal measures of the several different liquids, we shall find that they possess very different weights. The weight of a pint of water, a pint of oil, and a pint of mercury will differ very materially. The mercury will weigh 13.6 times more than water does, and the water will weigh a good deal more than the oil. TABLE SHOWING THE WEIGHT OF WATER. 1 Cubic inch is equal to .036 pounds. 12 Cubic inches 1 Cubic foot 1 Cubic foot 1.8 Cubic foot 35.8 Cubic feet 1 Cylindrical inch 12 Cylindrical inches 1 Cylindrical foot 1 Cylindrical foot 2.282 Cylindrical feet 45.64 Cylindrical feet 11.2 Imperial gallons 224 Imperial gallons 13.44 U. S. gallons 268.8 U. S. gallons .432 “ 62.5 “ 7.50 U. S. gallons. 112.00 pounds. 2240.00 “ .02827 “ .339 “ 49.08 ‘‘ 6.00 TJ. S. gallons, 112.00 pounds. 2240.00 “ 112.00 “ 2240.00 “ 112.00 2240.00 “ HAND-BOOK OF THE LOCOMOTIVE. TABLE SHOWING THE WEIGHT OF WATER AT DIFFERENT TEMPERATURES. Temperature Fahrenheit. Weight of a Cubic Foot in Pounds. Temperature Fahrenheit. Weight of a Cubic Foot in Pounds. 40° 62.408 172° 60.72 42° 62.406 182° 60.5 52° 62.377 192° 60.28 62° 62.321 202° 60.05 72° 62.25 212° 59.82 82° 62.15 230° 59.37 92° 62.04 250° 58.85 102° 61.92 275° 58.17 112° 61.78 300° 57.42 122° 61.63 350° 55.94 132° 61.47 400° 54.34 142° 61.30 450° 52.70 152° 61.11 500° 51.02 162° 60.92 600° 47.64 Water attains a minimum volume and a maximum density at 39° Fah. ; any departure from that tem- perature in either direction is accompanied by ex- pansion, so that 8° or 10° of cold produces about the same amount of expansion as 8° or 10° of heat. ANALYSIS OF WATER TAKEN FROM SIX DIFFERENT WELLS. Chloride sodium, 9.162 grains in a gallon. Carbonate lime, 7.103 “ “ Carbonate magnesia, 3.027 “ ** Sulphate lime, alumina, lithia, a trace of each. Chloride sodium, 9.087 grains in a gallon. Carbonate lime, 5.532 “ ‘‘ “ HAKD-BOOK OF THE LOCOMOTIVE. 33 TABLE SHOWING THE BOILING-POINT OP PKESH WATER AT DIFFERENT ALTITUDES ABOVE SEA-LEVEL. Boiling point in deg. Fah. Altitude above sea- level in feet. Boiling point in deg. Fah. Altitude above sea- level in feet. Boiling point in deg. Fah. Altitude above sea- level in feet. 184° 15221 195° 9031 206° 3115 185 14649 196 8481 207 2589 186 14075 197 7932 208 2063 187 13498 198 7381 209 1539 188 12934 199 6843 210 1025 189 12367 200 6304 211 512 190 11799 201 5764 212 sea-level =0 191 11243 202 5225 192 10685 203 4697 Below sea-level. 193 10127 204 ^ 4169 213° 1 511 194 9579 205 3642 1 AIR. The atmosphere is known to extend at least 45 miles above the earth. Its composition is about 79 measures of nitrogen . gas and 21 of oxygen ; or in other words, air consists of, by volume, oxygen 21 parts, nitrogen 79 parts; by weight, oxygen 77 parts, nitrogen 23 parts. According to Dr. Prout, 100 cubic inches of air at the surface of the earth, when the barometer stands at 30 inches, and at a temperature of 60® Fah., weighs about 31 grains, being thus about 815 times lighter than water, and 11,065 times lighter than mercury. C 34 HAND-BOOK OF THE LOCOMOTIVE. Since the air of the atmosphere is possessed of weight, it must be evident that a cubic foot of air at the surface of the earth has to support the weight o^ all the air directly above it, and that, therefore, the higher we ascend up in the atmosphere the lighter will be the cubic foot of air, or in other words, the farther from the surface of the earth, the less will be the density of the air. At the height of three and a half miles it is known that the atmospheric air is only half as dense as it is at the surface of the earth. From the nature of fluids, it follows, that the air of the atmosphere presses against any body which comes into contact with it; because fluids exert pres- sure in all directions, — upwards, downwards, side- wise, and oblique. It is also known that the pressure on any point is equal to the weight of all the particles of the fluid in a perpendicular line between the point in contact and the surface of the fluid. The amount of pressure of a column of air whose base is one square foot, and altitude the height of the atmosphere, has been found to be 2156 pounds avoirdupois, or very nearly 15 pounds of pressure on every square inch ; consequently, it is common to state the pressure of the atmosphere as equal to 15 pounds on the square inch. If any gaseous body or vapor, such as steam, exerts a pressure equivalent to 15 pounds on the square HAND-BOOK OF THE LOCOMOTIVE. 35 inch, then the foice of that vapor is said to be equal to one atmosphere ; if the vapor be equal to 30 pounds on every square inch, then it is equal to two atmospheres, and so on. Consequently, the atmos- pheric pressure is capable of supporting about 30 inches of mercury, or a column of water 34 feet high. It is also found that the pressure of the atmosphere is not constant even at the same place ; at the equator, the pressure is nearly constant, but is subject to greater change in the high latitudes. In some countries the pressure of the atmosphere varies so much as to support a column of mercury so low as 2.8 inches, and at other times so high as 31, the mean being 29.5, thus making the average pres- sure between 14 and 15 pounds on the square inch. But in scientific books," generally, the pressure is understood in round numbers to be 15 pounds, so that a pressure exerted equal to 1, 2, 3, 4, etc., atmos- pheres, means such a pressure as would support 30, 60, 90, 120, etc., inches of mercury in a perpendicular column, or 15, 30, 45, 60, etc., pounds on every square inch. Air is a very slow conductor of heat, and is some- times used as a non-conductor in hollow walls to prevent the radiation of heat. The pressure of the air differs at different lati- tudes; for instance, at 7 miles above the surface of the earth the air is four times lighter than it k* at the earth^s surface ; at 14 miles it is 16 times lighter, and at 21 miles it is 64 times lighter. HAND-BOOK OP THE LOCOMOTIVE. Under a pressure of tons to the square inch, air becomes as dense, and would weigh as much per cubic foot, as water. The greatest heat of air in the sun is about 140^^ Fah., and it probably never exceeds 145® Fah. If a given weight of air at 0® Fah. be raised in temperature to 461® Fah. under a constant pressure, it is expanded to twice its original volume ; and if heated from 0® Fah. to twice 461®, or 922®, its origi- nal volume is trebled. One cubic foot of pure air at 62® Fah. and 14.7 pounds per square inch pressure weighs .076097 pound, 1.217 ounces or 532.7 grains. Although the atmosphere may extend to the height of 45 miles, yet its lower half is so compressed as to occupy only 3J miles^ so greatly do the upper portions expand when relieved from pressure. Hence, at the height of 3 J miles, the elasticity of the atmos- phere is ^ ; at 7 miles, ^ ; at 10^ miles, ^ ; at 14 miles, j’g, etc. For the above reasons a pump in a higher region will not lift water to as great a height as in a lower one. It is also stated that the temperature of the atmosphere lowers or becomes colder at the rate of 1® Fah. for each 300 feet of ascent above the earth’s surface ; but this is liable to many exceptions, and varies much with local causes. HAND-BOOK OF THE LOCOMOTIVE. TABLE SHOWING THE EXPANSION OF AIR BY HEAT, AND THE INCREASE OF BULK IN PROPORTION TO INCREASE OF TEMPERATURE. Fahrenheit. Bulk. Fahrenheit Bulk. Temp. 32 Freezing-point. 1000 Temp. 75 Temperate 1099 33 (( 1002 u 76 Summer heat. 1101 (t 34 ft 1004 tt 77 it 1104 (( 35 ft 1007 tt 78 it 1106 (1 36 ft 1009 tf 79 ft 1108 (( 37 ft 1012 tt 80 ft 1111 (f 38 tf 1015 tt 81 it 1112 (C 39 tt 1018 tt 82 ft 1114 t( 40 tt 1021 ft 83 ft 1116 ft 41 ft 1023 tt 84 ft 1118 ft 42 it 1025 tf 85 it 1121 tf 43 ft 1027 tt 86 ft 1123 ft 44 tt 1030 ft 87 it 1125 ft 45 ft 1032 ff 88 tf 1128 ft 46 tt 1034 tt 89 tt 1130 if 47 ft 1036 it 90 if 1132 ft 48 ft 1038 it 91 tt 1134 ft 49 ft 1040 it 92 it 1136 ft 50 ft 1043 it 93 ft 1138 tt 51 tt 1045 tt 94 tt 1140 ft 52 tt 1047 tt 95 V it 1142 tf 53 ft 1050 it 96 Blood heat.... 1144 ft 54 ft 1052 it 97 if 1146 ff 55 ft 1055 tt 98 if 1148 tf 56 Temperate ... . 1057 it 99 it 1150 tt 57 it 1059 it 100 ft 1152 ft 58 tt 1062 It 110 Fever heat 112 1173 tt 59 ft 1064 tt 120 it 1194 tt. 60 ft 1066 it 130 it 1215 tt 61 ft 1069 tt 140 it 1235 tt 62 ft 1071 tt 150 It 1255 tf 63 ft 1073 tt 160 it 1275 ff 64 ft 1075 it 170 Spirits boil 176 1295 ft 65 (( 1077 ft 180 ft 1315 tt 66 ft 1080 it 190 it 1334 tf 67 It 1082 ft 200 tt 1364 tt 68 tt 1084 ft 210 ft 1372 ff 69 ft 1087 ff 212 Water boils... 1375 ft 70 ft 1089 ff 302 tt 1558 tt 71 ft 1091 ft 392 it 1739 tt 72 ft 1093 tf 482 tt 1919 tt 73 ft 1095 it 572 it 2098 u 74 ft 1097 it 680 ft 2312 4 9 38 HAND-BOOK OF THE LOCOMOTIVE. Resistance to Motion caused by the Atmosphere, — The resistance against a body moving in a fluid at rest is less than the resistance experienced by the same body placed at rest, in a fluid moving against it, which seems to denote that a fluid in motion separates itself less easily than a fluid at rest. Thin plates meet with a greater resistance from the air than a prismatic body presenting the same surface, and the resistance diminishes according as the prism is longer. But if the moving body be a lengthened prism, the air in passing along its sides loses a certain propor- tion of its velocity, and, consequently, on reaching the hind-face of the prism, extends itself behind it with a force partially diminished, consequently pro- ducing a partial vacuum. RESISTANCE OF AIR AGAINST RAILROAD TRAINS. To dispense with all calculation relative to the re- sistance of the air, the following table (pp. 40, 41) is subjoined to show its intensity for all velocities from 5 to 35 miles per hour, and for surfaces of from 10 to 100 square feet. Were it required to perform the calculation for a velocity not contained in the table, it would evidently suffice to seek the resistance corresponding to half that velocity, and to multiply the resistance found by 4. Or, on the contrary, to seek the resistance corre- HAND-BOOK OF THE LOCOMOTIVE. 39 spending to the double of the given velocity, and to take a quarter of the result. The resistance of the air against a surface of 100 square feet, at the velocity of 50 miles per hour, is equal to four times the resistance of the air against the same surface at 25 miles per hour. By means of the table in question will be ob- tained, without calculation, the resistance of the air expressed in pounds for any velocity of the moving body. But it must be understood that the table sup- poses the atmosphere to be at rest. If, then, there be a wind of some intensity, favor- able to the motion, or contrary to it, account must be taken of that, and in order to effect this, it will be necessary to observe that if the wind is opposed, the train will move through the air with the velocity equal to the difference between its own absolute ve- locity and that of the wind. But if, on the contrary, the wind is favorable to the motion, the effect of the velocity of the train through the air will be equal to the sum of its own velocity augmented by that of the wind. On such cases the velocity of the wind must be first measured by noting the time taken by some light body, such as paper, in traversing a space pre- viously measured on the ground. If the wind, instead of being precisely contrary or favorable to the motion, should exert its action in an oblique direction, it would tend to displace all the 40 HAND-BOOK OF THE LOCOMOTIVE. cars laterally, and, consequently, from the conical form of the wheels, all those on the farther side from the wind would turn on a different diameter than those on the side towards the wind. The resistance produced will, therefore, be the same as that which would take place on a curve on which the effect of the centrifugal forces were not corrected, and that resistance would necessarily be very considerable. TABLE SHOWING THE KESISTANCE OF AIR AGAINST RAILROAD TRAINS. Velocity of motion in miles per hour. Resistance of the air in pounds per square feet of surface. Resistance of the air in pounds; the effective surface of the train in square feet, being 20 ft. 30 ft. 40 ft. 50 ft. 60 ft. 70 ft. 80 ft. 90 ft. 100 ft. miles. lbs. lbs. lbs. lbs. lbs. lbs. lbs. lbs. lbs. lbs. 5 .07 1 2 3 3 4 5 5 6 7 6 .10 2 3 4 5 6 7 8 9 10 7 .13 3 4 5 7 8 9 . 11 12 13 8 .17 3 5 7 9 10 12 14 15 17 9 .22 4 7 9 11 13 15 17 20 22 10 .27 . 5 8 11 13 16 19 22 24 27 11 .33 7 10 13 16 20 23 26 29 33 12 .39 8 12 15 19 23 27 31 35 39 13 .45 9 14 18 23 27 32 36 41 45 14 .53 11 16 21 26 32 37 42 47 53 15 .60 12 18 24 30 36 42 48 54 60 16 .69 14 21 28 34 41 48 55 62 69 17 .78 16 23 31 39 47 54 62 70 78 18 .87 17 26 35 44 52 61 70 78 87 19 .97 19 29 39 49 58 68 78 87 97 20 1.07 22 32 43 54 65 75 86 97 107 21 1.19 24 36 47 59 71 83 95 107 119 22 1.30 26 39 52 65 78 91 104 117 130 23 1.42 28 43 57 71 85 100 114 128 142 24 1.55 31 47 62 78 93 109 124 140 155 HAND-BOOK OF THE LOCOMOTIVE. 41 TABLE — ( Continued) SHOWING THE KESISTANCE OF AIR AGAINST RAILROAD TRAINS. Velooity of motion in miles per hour. Resistance of the air in pounds per square feet of surface. Resistance of the air in pounds ; the effective surface of the train in square feet ^ being 20 ft. 30 ft. 40 ft. 50 ft. 60 ft. 70 ft. 80 ft. 90 ft. 100 ft. miles. lbs. lbs. lbs. lbs. lbs. lbs. lbs. lbs. lbs. lbs. • 25 1.68 34 50 67 84 101 118 134 151 168 26 1.82 36 55 73 91 109 127 146 164 182 27 1.96 39 59 78 98 118 137 157 176 196 28 2.11 42 63 84 106 127 148 169 190 211 29 2.26 45 68 90 113 136 158 181 203 226 30 2.42 48 73 97 121 145 169 194 218 242 31 2.58 52 77 103 129 155 181 206 232 258 32 2.75 55 83 110 138 165 193 220 248 275 33 2.93 59 88 117 147 176 205 234 264 293 34 3.11 62 93 124 156 187 218 249 280 311 35 3.29 66 99 132 165 197 230 263 296 329 Rule to calculate Resistance of Train at a given speed. Square the speed in miles per hour, divide this by 171, and add 8 to the quotient. Result is the resist- ance at the rails in pounds per ton weight. Resistance of Trains on a level at different speeds in pounds per Ton of Load. The resistance of curves may be reckoned as 1 per cent, for each degree of curve occupied by the train. Imperfections of road vary from 5 to 40 per cent. Strong side winds vary 20 per cent. Velocity of trains in miles per hour 10 15 20 30 40 50 Eesistance on straight lines, lbs. per ton 8^ 9i m m m m Eesistance with sharp curves and strong winds 13 14 m 20 26 34 4 * 42 HAND-BOOK OF THE LOCOMOTIVE, COMPAKATIVE SCALE OF ENGLISH, FEENCH, AND GEKMAN THEEMOMETEES. Boiling-point 100 of water. 70 40 10 10 Mercury freezes. 40 212 — 200 — — 190 — 180 170 160 150 140 — 130 — _ — 120 — 110- — 100 — 90 — 80 — 70 — 60 — 50 40 30 20 — 10 — ZERO — _ 10 — 20 _ 30 40 — - 80 Boiling-point of water. - 70 60 60 - 40 - 30 20 - 10 - 0 Freezing-point - 10 - 20 30 40 The 0 of Eeaumur equal 32® Fah. HAND-BOOK OF THE LOCOMOTIVE. 43 THE THERMOMETER. The Thermometer is an instrument for measuring variations of heat or temperature. The principle upon which thermometers are constructed, is the change of volume which takes place in bodies, when their temperature undergoes an alteration. Gener- ally speaking, all bodies expand when heated, and contract when cooled, and in such a manner that under the same circumstances of temperature they return to the same dimensions. But as it is necessary, not merely that expansion and contraction take place, but that they be capable of being conveniently observed and measured, only a small number of bodies are suitable for thermo- metrical purposes. Solid bodies, for example, undergo so small a change of volume, with moderate variations of temperature, that they are in general only used for measuring very high temperatures, as the heat of furnaces of melting metals, etc. The properties of Mercury, which render it prefer- able to all other liquids (unless for particular pur- poses), ai’e these: 1. It supports, before it boils and is reduced to vapor, more heat than any other fluid, and endui;e.s a greater cold than would congeal most other liqij^s. 2. It takes the temperature of the medium in which it is placed more quickly than any other fluid. Count Rumford found that mercury 44 HAND-BOOK OF THE LOCOMOTIVE. was lieated from the freezing- to the boiling-point of water in 58 seconds, while water took 133 seconds, and air 617 seconds, the heat applied being the same in all the three cases. 3. The variations of its volume, within limits, which include the temperatures most frequently required to be observed, are found to be perfectly regular and proportional to the variations of temperature. The Mercurial Thermometer consists of a bulb and stem of glass of uniform bore. A sufficient quantity of mercury having been introduced, it is boiled to expel the air and moisture, and the tube is then hermetically sealed. The standard points are ascertained by immersing the thermometer in melting ice, and in the steam of water boiling under the pressure of 14.7 pounds on the square inch, and marking the positions of the top of the column ; the interval between those points is divided into the proper number of degrees — 100 for the Centigrade scale ; 180 for Fahrenheit’s ; and 80 for Reaumur^ s. In Fahrenheit’s time it was supposed that the greatest degree of cold attainable was reached by mixing snow and common salt, or snow and sal- ammoniac. A thermometer plunged into a mixture of this kind was found to fall much below the point indicated by melting ice. The point to which the mercury fell by contraction, when plunged in this mixture, Fahrenheit marked 0 ; the interval be- tween this and the freezing-point he divided into HAND-BOOK OF THE LOCOMOTIVE. 45 thirty-two equal divisions, hence the freezing-point came to be indicated by 32°. Then equal divisions were continued upwards, and the mercury, by expansion, reaching 212°, when the thermometer was immersed in boiling water, this 212° was called the boiling-point. This is briefly the reason for Fahrenheit adopting his method of division, and why he has 212° — 32° = 180° between the freezing and the boiling points. But a much lower temperature than Fahrenheit’s 0° has been observed in cold countries, and as mer- cury becomes solid at 39° Fahrenheit below freezingy it would be the most accurate limit to the scale, as it would register the utmost extremes of heat and cold to which the mercurial thermometer is sensible. Centigrade Scale. — On this scale the space be- tween the freezing- and the boiling-points of water is divided into equal parts, the zero point being placed, as in Eeaumur’s, at freezing. This division being in harmony with our decimal arithmetic, is better adapted than Fahrenheit’s or Reaumur’s scale for scientific purposes. Reaumur’s Thermometer. — In Reaumur’s ther- mometer the melting-point of ice is taken as zero, and the distance between that and the boiling-point for water is divided into 80 equal parts. Reaumur having observed that between those temperatures spirits of wine (which he used for the thermometric fluid) expanded from 1,000 to 1,080 parts. This division soon became general in France and other 46 HAND-BOOK OP THE LOCOMOTIVE. countries, and a great number of valuable observa^ tions have been recorded in terms of it; but it is now seldom used in works of science. Change of Zero. — There is a circumstance con- nected with the mercurial thermometer which re- quires to be attended to, when very exact determina- tions of temperature are to be made, as it has been observed that when thermometers which have been constructed for several years are placed in melting ice, the mercury stands in general higher than the zero point of the scale ; and this circumstance, which renders the scale inaccurate, has been usually ascribed to the slowness with which the glass of the bulb ac- quires its permanent arrangement, after having been heated to a high degree in boiling the mercury. In very nice experiments it is always necessary to verify the zero point; for it was found that when thermometers have been kept during a certain time in a low temperature, the zero point rises, but falls when they have been kept in a high temperature, and this remark applies equally to old thermometers and to those which have been recently constructed. Absolute Zero. — An absolute zero is a theoretical and imaginary term, as an absolute zero is only sup- posed to be the point where heat-motion ceased en- tirely, and is fixed at 461^ Fah. below the zero of the common thermometer. The rate of expansion of mercury with rise of temperature increases as the temperature becomes higher ; from which it follows, that if a thermometer HAND-BOOK OF THE LOCOMOTIVE. 47 showing the dilation of mercury simply were made to agree with an air thermometer at 82° and 212°, the mercurial thermometer would show lower tem- peratures than the air thermometer between those standard points and higher temperatures beyond them. Spirit Thermometers are used to measure temper- atures at and below the freezing-point of mercury. Their deviations from the air thermometer are greater than those of the mercurial thermometer. Solid Thermometers. — Solid thermometers are sometimes used, which indicate temperatures by showing the difference between the expansions of a pair of bars of two substances whose rates of ex- pansion are different. When such thermometers are used to indicate temperatures higher than the boiling point of mercury under one atmosphere (about 676° Fah.), they are called Pyrometers. Fixed Temperatures are the boiling-point* for water and the melting-point for ice. Rules for comparing Degrees of Temperature indicated by different Thermometers : Rule I. — Multiply degrees of Centigrade by 9, and divide by 5 ; or multiply degrees of Eeaumur by 9, and divide by 4. Add 82 to the quotient in either case, and the sum is degrees of Fahrenheit. Rule II. — From degrees of Fahrenheit subtract 82 ; multiply the remainder by 5, and divide by 9 for degrees of Centigrade; or multiply by 4 and divide by 9 for degrees of Reaumur. 48 HAND-BOOK OF THE LOCOMOTIVE. DANFORTH PASSENGER LOCOMOTIVE. HAND-BOOK OF THE LOCOMOTIVE. 49 ELASTIC FLUIDS AND VAPORS. Elastic fluids are divided into two classes — perma- nent gases and vapors. The gases cannot be liquefied under ordinary conditions of pressure and tempera- ture ; whereas the vapors are readily reduced to the liquid form by pressure or diminution of tempera- ture. In respect of their mechanical properties there is, however, no essential difference between the two classes. Elastic fluids, in a state of equilibrium, are sub- ject to the action of two forces: namely, gravity, and a molecular force acting from particle to particle. Gravity acts on the gases in the same manner as on all other material substances ; but the action of the molecular forces is altogether different from that which takes place among the elementary particles of solids and liquids; for, in the case of solid bodies, the molecules strongly attract each other (hence re- sults their cohesion), and, in the case of liquids, exert a feeble or evanescent attraction, so as to be indifferent to internal motion ; but, in the case of the gases, the molecular forces are repulsive, and the molecules, yielding to the action of these forces, tend incessantly to recede from each other, and, in fact, do recede until their further separation is prevented by an ex- terior obstacle. Thus, air confined within a close vessel exerts a constant pressure against the interior surface, which 5 D 50 HAND-BOOK OF THE LOCOMOTIVE. is not sensible, only because it is balanced by the equal pressure of the atmosphere on the exterior sur- face. This pressure exerted by the air against the sides of a vessel within which it is confined, is called its elasticity, elastic force, or tension. Conditions of Equilibrium. — In order that all the parts of an elastic fluid may be in equilibrium, one condition only is necessary : namely, that the elastic force be the same at every point situated in the same horizontal plane. This condition is likewise neces- sary to the equilibrium of liquids, and the same cir- cumstances give rise to it in both cases : namely, the mobility of the particles, and the action of gravity upon them. The density of bodies being inversely as their volumes, the law of Mariotte may be otherwise ex- pressed by saying the density of an elastic fluid is directly proportional to the pressure it sustains. Under the pressure of a single atmosphere, the density of air is about the 770th part of that of water ; whence it follows that, under the pressure of 770 atmospheres, air is as dense as water. The average atmospheric pressure being thus equal to that of a column of water of about 34 feet in altitude at the level of the sea, at a depth of 26,180 (equals 770 multiplied by 34) feet, or 5 miles, air would be heavier than water; and though it should still remain in a gaseous state, it would be incapable of rising to the surface. HAND-BOOK OF THE LOCOMOTIVE. 51 CALORIC. The ordinary application of the word heat implies the sensation experienced on touching a body hotter, or of a higher temperature ; whilst the term caloric provides for the expression of every conceivable existence of temperature. Caloric is usually treated as if it were a material substance; but, like light and electricity, its true nature has yet to be determined. Caloric passes through difierent bodies with differ- ent degrees of velocity. This has led to the division of bodies into conductors and non-conductors of ca- loric; the former includes such bodies as metals, which allow caloric to pass freely through their sub- stance, and the latter comprises those that do not give an easy passage to it, such as stones, glass, wood, charcoal, etc. Radiation of Caloric. — When heated bodies are exposed to the air, they lose portions of their heat by projections in right lines into space from all parts of their surface. Radiation is effected by the nature of the surface of the body : thus, black and rough surfaces radiate and absorb more heat than lignt and polished surfaces. Bodies which radiate heat best, absorb it best. Reflection of Caloric differs from radiation, as the caloric is in this case reflected from the surface without entering the substance of the body. Hence, 52 HAKD-BOOK OF THE LOCOMOTIVE. the body which radiates, and consequently absorbs most caloric, reflects the least, and vice versa. Latent caloric is that which is insensible to the touch, or incapable of being detected by the ther- mometer. The quantity of heat necessary to enable ice to assume the fluid state, is equal to that which would raise the temperature of the same weight of water, 142° Fah., and an equal quantity of heat is set free from water when it assumes the solid form. Sensible caloric is free and uncombined, passing from one substance to another, aflecting the senses in its passage, determining the height of the thermometer, and giving rise to all the results which are attributed to this active principle. Evaporation produces cold, because caloric must be absorbed in the formation of vapor, a large quan- tity of it passing from a sensible to a latent state, the capacity for heat of the vapor formed being greater than that of the fluid from which it proceeds. HEAT. Heat is one form of mechanical power, or, more properly, a given quantity of heat is the equivalent of a determinate amount of mechanical power ; and as heat is capable of producing power, so contrari- wise power is capable of producing heat. As it becomes necessary to have a standard for measuring the amount of heat absorbed or evolved HAND-BOOK OF THE LOCOMOTIVE. 53 during any operation, in this country the standard unit is the amount of heat necessary to raise the temperature of a pound of water 1° Fah., or from 32° to 33° Fah. Specific Heat. — Different bodies require very different quantities of heat to effect in them the same change of temperature. The capacity of a body for heat is termed its “ specific heat,” and may be defined as the number of units of heat necessary to raise the temperature of 1 pound of that body 1° Fah. When a substance is heated it ekpands, and its temperature is increased. It is evident, therefore, that heat is required both to raise the temperature and to increase the distance between the particles of the substance. The heat used in the latter case is converted into interior work, and is not sensible to the thermome- ter ; but it will be given out, if the temperature of the substance is reduced to the original point. Thus, while heat is apparently lost, it is only stored up, ready to do work, and the substance pos- sesses a certain amount of potential energy, or possi- bility of doing work. Now, as difierent substances vary greatly in their molecular constitution, expanding and contracting the same amount with widely differing degrees of force, it is to be^ expected that the quantity of heat that will raise one substance to a given temperature 5 * M HAND-BOOK OF THE LOCOMOTIVE. may produce a less or greater degree of sensible heat to another ; and we find in practice that such is the case. The condition of heat is measured as a quantity, and its amounts in diflferent bodies and under differ- ent circumstances are compared by means of the changes in some measurable phenomenon produced by its transfer or disappearance. In so using changes of temperature, it is not to be taken for granted that equal differences of tempera- ture in the same body correspond to equal quantities of heat. This is the case, indeed, for perfectly gase- ous bodies ; but that is a fact only known by experi- ment. On bodies in other conditions, equal differences of temperature do not exactly correspond to equal quantities of heat. To ascertain, therefore, by an experiment on the changes of temperature of any given substances, what proportion two quantities of heat bear to each other, the only method which is of itself sufficient, in the absence of all other experi- mental data, is the comparison of the weights of that substance which are raised from the same low temperature to a high or fixed temperature. The Unit of Heat. — The unit of heat, or thermal unit employed, is the quantity of heat, as before stated, that would raise 1 pound of pure water 1° Fah., or from 39"^ to 40^ Fah. The reason for selecting * that part of the scale HAND-BOOK OF THE LOCOMOTIVE. 55 which is nearest the temperature of the greatest density of water, is because the quantity of heat corresponding to an interval of one degree in a given weight of water is not exactly the same in different parts of the scale of temperature. Latent Heat. — Latent heat means a quantity of heat which has disappeared, having been employed to produce some change other than elevation of tem- perature. By exactly reversing that change, the quantity of heat which had disappeared is repro- duced. When a body is said to possess or contain so much latent heat, what is meant is simply this ; that the body is in a condition into which it was brought from a former different condition by transferring to it a quantity of heat which did not raise its tem- perature, the change of condition having been dif- ferent from change of temperature, and that by restoring the body to its original condition in such a manner as exactly to reverse the former process. The quantity of heat formerly expended can be re- produced in the body and transferred to other bodies. When a body passes from the solid to the liquid state, its temperature remains stationary, or nearly so, at a certain melting point, during the whole oper- ation of melting, and in order to make that opera- tion go on, a quantity of heat must be transferred to the substance melted, having a certain amount for each unit of weight of the substance. That heat 56 HAND-BOOK OF THE LOCOMOTIVE. does not raise the temperature of the substance, but disappears in causing its condition to change from the solid to the liquid state. When a substance passes from the liquid to the solid state, its temperature remains stationary, or nearly so, during the whole operation of freezing ; a quantity of heat equal to the latent heat of fusion is produced in the body, and in order that the oper- ation of freezing may go on, that heat must be transferred from that body to some other substance. Sensible Heat. — Sensible heat is that which is sensible to the touch or measurable by the ther- mometer. Mechanical Equivalent of Heat. — The mechani- cal equivalent of heat is the amount of work per- formed by the conversion of one unit of heat into work. This has been determined to be equal in amount to the work required to raise 772 pounds one foot high, or one pound 772 feet high. And as heat and work are mutually convertible, if a body weighing one pound, after falling through a height of 772 feet, were to have its motion suddenly arrested, it would develop sufficient heat to raise the tempera- ture of a pound of water one degree. If a pound of water, at a temperature of 212° Fah., is converted into steam, the latter will have a volume of about 27 J cubic feet. Now, suppose that the water is evaporated in a long cylinder, of exactly one foot cross section, open to the atmosphere at the HAND-BOOK OF THE LOCOMOTIVE. 57 top. When all the water in the cylinder has disap- peared, there will be a column of steam 27i feet high, which has risen to this height against the pres- sure of the atmosphere. The pressure of the air being nearly 15 pounds per square inch, the pressure per square foot is 2,117 pounds ; and the external work performed by the water, in changiug to steam, will be an amount re- quired to raise 2,117 pounds to a height of 27i feet, or about 57,688 foot-pounds. Now, since 772 foot-pounds of work require one unit of heat, the external work will take up 57,688 divided by 772, equals 74.72 units of heat. But it has been shown that the total number of units of heat required to change water into steam is about 968 (more accurately, 966.6). Hence the in- ternal work will be equal to an amount developed by the conversion of 966.6 less 74.72, equals 891.88 units of heat into work, and this will equal 891.88, multiplied by 772, equals 688,531 foot-pounds. Mechanical Theory of Heat. — The mechanical theory of heat is now generally adopted. It con- siders that heat and work are interchangeable, and on this theory can be explained what becomes of the latent heat. All solid bodies are supposed to be made up of molecules, which are not in contact, but are prevented from separating by a force called cohesion. If a body is heated to a sufficient temperature, the 58 HAND-BOOK OF THE LOCOMOTIVE. force of expansion becomes equal to that of cohesion, and the body is liquefied ; and if still more heat is applied, the force of expansion exceeds that of co- hesion, and the liquid becomes a vapor. But in each of these changes work is performed, and the heat that is supplied is converted into work. For instance, if ice is at a temperature of 32°, and heat is applied, this is converted into the work that is developed in changing ice into water, and we say that heat becomes latent, and when water is at 212°, and we continue to apply heat; this is con- verted into the work that must be done in changing the water into steam. Dynamic Equivalent of Heat. — It is a matter of ordinary observation that heat, by expanding bodies, is a source of mechanical energy ; and conversely, that mechanical energy, being expanded either in compressing bodies or in friction, is a source of heat. In all other cases in which heat is produced by the expenditure of mechanical energy, or mechanical energy by the expenditure of heat, some other change is produced besides that which is principally con- sidered ; and this prevents the heat and the mechan- ical energy from being exactly equivalent. Power of Expansion by Heat. — When bodies ex- pand, the molecules of which they are composed are pushed farther asunder by the oscillatory motion communicated to them. The heat may be described as entering the substance and immediately setting to HAND-BOOK OF THE LOCOMOTIVE. 59 work to separate the particles. The power or energy it exerts to do this is immense. Moleculap or Atomic Force of Heat. — All mole- cules are under the influence of two opposite forces. The one, molecular attraction, tends to bring them together ; the other, heat, tends to separate them ; its intensity varies with its velocity of vibration. Molec- ular attraction is only exerted at infinitely small distances, and is known under the name of cohesion, affinity, and adhesion. Total or Actual Heat. — When a substance, by the expenditure of energy in friction, is brought from a condition of total privation of heat to any particular condition as to heat. Then if we, from the total energy so expanded, subtract, first, the mechanical work performed by the action of the substance on external bodies, through changes of its volume, dur- ing such heating; secondly, the mechanical work due to mutual actions between the particles of the substance itself during such heating, the remainder will represent the energy which is employed in mak- ing the substance hot. Communication of Heat. — Heat may be commu- nicated from a hot body to a cold one in three ways — by radiation, conduction, and circulation. The rapidity with which heat radiates varies, other things being equal, as the square of the tem- perature of the hot body in excess of the tempera- ture of the cold one ; so that a body, if made twice 60 HAND-BOOK OF THE LOCOMOTIVE. as hot, will lose a degree of temperature in one-fourth of the time ; if made three times as hot, it will lose a degree of temperature in one-ninth of the time, and so on in all other proportions. Transmission of Heat. — Tredgold and others have made experiments to ascertain the rate at which heat is transferred from metal to gases and from gases to metal. Other things being equal, it has been found that the rate of transference is as the differ- ence of temperature. But in practice the conditions are different from those in the experiment ; generally, in experiments, the air has been still, and the gases moving under natural draft ; but in locomotive prac- tice, the velocity of the gases is so great as to render the results of most experiments inapplicable. Effects of Heat on the Circulation of Water in Boilers. — As the particles of water rise heated from the bottom of the boiler, other particles necessarily subside into their places, and it is a point of con- siderable importance to ascertain the direction in which the currents approach the plate to receive heat. A particle of water cannot leave the heated plate until there is another particle at hand to occupy its position ; and, therefore, unless a due succession in the particles is provided for, the plate cannot get rid of its heat, and the proper formation of steam is hindered. But it must be understood that vaporization does not depend on the quantity of heat applied to the HAND-BOOK OF THE LOCOMOTIVE. 62 plate, but on the quantity of heat abstracted from it by the particles of water. Medium Heat. — The medium heat of the globe is placed at 50° ; at the torrid zone 75° ; at moderate climates 50° ; near the Polar regions 36° Fah. The extremes of natural heat are from — 70° to 120° ; of artificial heat, from — 166° to 36000° Fah. LATENT HEAT OF FUSION. FLUIDS. VAPORS. Fah. Ice 142° Sulphur 168 Lead 9.8 Beeswax 176 Zinc 60.6 Fah. Steam 966.6° Vinegar 875 Ammonia 860 Alcohol 372 Ether 174 TABLE SHOWING THE EFFECTS OF HEAT UPON DIFFERENT BODIES. Fah. Cast-iron, thoroughly ) smelted J Fine gold melts 2282 Fine silver “ 1832 Copper “ 2160 Brass “ 1900 Red heat, visible by day 1077 Iron red-hot in twi- ) qq. light 1 Common fire 790 Fah. Lead melts. 608° Bismuth “ 504 Tin 446 Tin and Bismuth, ) equal parts, melt... j Tin, 3 parts. Bismuth S 5, and Lead 2 parts, > 212 melt J Alcohol boils 174 Ether 98 Iron, bright red in the | dark j Zinc melts 680 Quicksilver boils 648 Linseed oil 600 Human blood (heat of) 98 Strong wine freezes 20 Brandy “ .... 7 Mercury melts — 39 6 62 HAND-BOOK OF THE LOCOMOTIVE, roads, has a brighter record than any other branch of mechanical engineering. HAND-BOOK OF THE LOCOMOTIVE. 63 COMBUSTION. Combustion or burning is a rapid chemical com- bination. In the ordinary sense of the word, com- bustible means a body capable of combining rapidly with oxygen so as to produce heat. No substance in nature is combustible of itself, to whatever degree of heat it may be exposed ; nor can it be ignited only when in presence of or in mechan- ical mixture with air, or its vital element, oxygen, because combustion is continuous ignition, and can only be made to exist by maintaining in the combus- tible mixture the heat necessary to ignite it. Chemical combination, in every case, is accom- panied by a production of heat; every decomposi- tion, by a disappearance of heat equal in amount to that which is produced by the combination of the elements which are to be separated. Y"hen a complex chemical action takes place in which various combinations and decompositions occur simultaneously, the heat obtained is the excess of the heat produced •by the combinations above the heat, which disappears in consequence of the decomposi- tions. Sometimes the heat produced is subject to a further deduction, on account of heat which disappears in melting or evaporating some of the substances which combine either before or during the act of combina- tion. 64 HAND-BOOK OF THE LOCOMOTIVE. Substances combine chemically in certain proper- tions only. To each of the substances known in chemistry, a certain number can be assigned, called its chemical equivalent, having these properties: — 1st. That the proportions by weight in which sub- stances combine chemically can all be expressed by their chemical equivalents, or by simple multiples of their chemical equivalents. 2d. That the chemical equivalent of a compound is the sum of the chemical equivalents of its constituents. Chemical equivalents are sometimes called atomic weights or atoms, in accordance with the hypothesis that they are proportional to the weights of the sup- posed atoms of bodies, or smallest similar parts into which bodies are assumed to be divisible by known forces. The term atom is convenient from its short- ness, and can be used to mean “chemical equivalent’’ without necessarily affirming or denying the hypoth- esis from which it is derived, and which, how prob- able soever it may be, is, like other molecular hypotheses, incapable of absolute proof. The chief elementary combustible constituents of ordinary fuel are carbon and hydrogen. Sulphur is another combustible constituent of ordinary fuel, but its quantity is small and its heating power of no practical value. Coal is composed, so far as combustion is con- cerned, of solid carbon and a gas consisting of hy- drogen and carbon. HA2S^D-B00K OF THE LOCOMOTIVE. 65 When the coal is heated, it first discharges its gas ; the solid carbon left then ignites in presence of oxy- gen, and will retain the temperature necessary to combustion so long as oxygen is supplied. The Ingredients of Fuel. — Fixed or free carbon which is left in the form of charcoal or coke after the volatile ingredients of the fuel have been distilled away. This ingredient burns either wholly in the solid or partly in the solid and partly in the gaseous state ; the latter part being first dissolved by previ- ously formed carbonic acid, as already explained. Hydrocarbons, such as gas, pitch, tar, naphtha, etc., all of which must pass into the gaseous state before being burned. If mixed on their first issuing from among the burning carbon with a large quantity of air, these inflammable gases are completely burned, with a transparent blue flame, producing carbonic acid and steam. Mixture of Fuel and Air. — In burning charcoal, coke, and coals which contain a small proportion only of hydrocarbons, a supply of air suflicient for complete combustion will enter from the ash-pit through the bars of the grate, provided there is a sufficient draught, and that care is taken to distrib- ute the fresh fuel evenly over the fire, and in mod- erate quantities at a time. Available Heat of Combustion. — The available heat of combustion of one pound of a given sort of fuel, is that part of the total heat of combustion 6* E 66 HAND-BOOK OF THE LOCOMOTIVE. which is communicated to the body, to heat which the fuel is burned. Anthracite Coal. — The chemical composition of anthracite coal is similar to charcoal, from which it differs chiefly in its form, being very hard and com- pact, and in the greater quantity of ashes which it contains. It is, like charcoal, unaltered in form after exposure to the strongest heat; even after passing through a blast furnace it has equally as sharp edges, and is in form exactly as it was before. COMPOSITIONS OF DIFFEEENT KINDS OF ANTHRACITE COAL. Carbon. Volatile matter. Ashes. Specific gravity. Lehigh coal 88.50 7.50 4.00 1.61 Schuylkill coal 92.07 5.03 2.90 1.57 Pottsville 94.10 1.40 4.50 1.50 Pinegrove... 79.57 7.15 3.28 1.54 Wilkesbarre 88.90 7.68 3.49 1.40 Carbondale 90.23 7.07 2.70 1.40 The analysis of anthracite shows good coal of that class to be composed of 90.45 carbon, 2.43 hydro- gen, 2.45 oxygen, some nitrogen, and 4.67 ashes. The ashes generally consist, like those of bitumi- nous coal, of silex, alumina, oxide of iron, and chlorides, which generally evaporate and condense on cold objects in the form of white films. Anthracite is not so inflammable as either dry wood HAND-BOOK OF THE LOCOMOTIVE. 67 or bituminous coal, but it may be made to burn quite as vividly as either, by exposing it to a strong draft, or in a large mass to the action of the air. The Quantity of Air Required for the Combustion of Anthracite Coal. — In view of the quantity of oxy- gen required to unite chemically with the various constituents of the coal, we find that in 100 pounds of anthracite coal, consisting of 91 per cent, of carbon and 9 per cent, of the other matter, it will be necessary to have 242.66 pounds of oxygen, since to saturate a pound of carbon by the formation of carbonic acid requires 21 pounds of oxygen. To saturate a pound of hydrogen in the formation of water, requires 8 pounds of oxj^gen ; hence 3.46 pounds of hydrogen will take 27.68 pounds of oxygen for its saturation. If then we add 242.66 pounds of oxygen for its saturation, 270.34 pounds of oxygen are required for the combustion of 100 pounds of coal. A given weight of air contains nearly 23.32 per cent, of oxygen ; hence to obtain 270.34 pounds of oxygen, we must have about four times that quan- tity of atmospheric air, or, more accurately, 1159.5 pounds of air for the combustion of 100 pounds of coal. A cubic foot of air at ordinary temperatures weighs about .076 pounds; so that 100 pounds of coal re- quire 15,254 cubic feet of air, or 1 pound of coal requires about 152 cubic feet of air, supposing every atom of the oxygen to enter into combination. 68 hahd-book: of the locomotive. But as from one-third to one-half of the air passes unconsumed through the fire, an allowance of 240 cubic feet of air for each pound of coal will be a small enough allowance to answer the requirements of practice, and in some cases as much as 320 cubic feet will be required. The Evaporative Efficiency of a Pound of Anthra- cite Coal. — The evaporative efiScacy of a pound of ckrbon has been found, experimentally, to be equiva- lent to that necessary to raise 14,000 pounds of water through 1 degree, or 14 pounds of water through 1000 degrees, supposing the whole heat generated to be absorbed by the water. Now, if the water be raised into steam from a tem- perature of 60°, then 1118.9° of heat will have to be imparted to it to convert it into steam of 15 pounds pressure per square inch; 14,000 divided by 1118.9 equals 12.5 pounds will be the number of pounds of water, therefore, which a pound of carbon can raise into steam of 15 pounds pressure from a temperature of 60°. This, however, is a considerably larger re- sult than can be expected in practice. Bituminous Coal. — Under this class we range all that mineral coal which forms coke, that is, it swells upon being exposed to heat, burns with a bright flame, blazes, and after the flame disappears there remains a spongy, porous mass — coke — which burns without flame like charcoal. In its composition we find chiefly carbon, oxygen. HAND-BOOK OF THE LOCOMOTIVE. 69 hydrogen, nitrogen, sulphur, and ashes, with a little water, which has been absorbed. The following table shows the comparative compo- sition of various sorts of mineral fuel : Carbon. Hydrogen. Oxygen and Nitrogen. Ashes. Turf 58.09 5.93 : 31.37 4.61 Brown Coal 71.71 4.85 21.67 1.77 Hard Bituminous CoaL 82.92 6.49 10.86 0,13 Cannel Coal 83.75 5.66 8.04 2.55 Cooking or Baking Coal 87.95 - 5.24 5.41 1.40 Anthracite — 91.98 3.92 3.16 0.94 An essential condition in forming coke is that the coal, on being heated, swells and changes into irreg- ular spongy masses, which adhere intimately together. This operation is designed to expel sulphur and hy- drogen, and form a coal which is not altered by heat. The sulphur cannot be entirely separated from coke, or from carbon, no matter how high the heat may be ; neither can all the hydrogen be removed from carbon by simply heating the compound. If oxygen is admitted to these combinations, both sulphur and hydrogen may be almost entirely expelled, that is, provided the oxygen is not introduced under too high or too low a heat. The most important point, and one which has a direct bearing upon the value of coal, is the quantity of heat which it can evolve in combustion. 70 HAND-BOOK OF THE LOCOMOTIVE. If we assume that the quantity of ashes is equal in the four substances mentioned below, that is, 5 per cent, in each, and suppose further that pine charcoal furnishes 100 parts of heat, the following table shows the quantity which must be liberated in their per- fect combustion. Kind of Coal. Carbon. Hydrogen. Water. Quality oi Heat. Brown Coal 69 3 23 78 Cooking Coal 75 4 16 87 u u 78 4 13 90 Anthracite Coal 85 3 7 94 Pure Carbon 100 ... ... 100 Bituminous coal, like all other fuel, is a compound substance, which may be decomposed by heat into several distinct elements — generally five or six at least. So far as relates to combustion, we are con- cerned principally with but two of these, viz., solid carbon, represented by coke, and hydrogen, generally known under the indefinite term of “gas.’’ These two elements contain principally the full heating qualities of the coal. The carbon, so long as it re- mains as such, is always solid and visible. The hydrogen, when driven from the coal by heat, carries with it a portion of carbon, the gaseous com- pound being known as carburetted hydrogen. A ton of 2,000 pounds of average bituminous coal contains, say 1,600 pounds, or 80 per cent, of carbon. HAND-BOOK OF THE LOCOMOTIVE. 71 100 pounds, or 5 per cent, of hydrogen, and 300 pounds, or 15 per cent, of oxygen, nitrogen, sulphur, sand and ashes. But if this coal be coked, the 100 pounds of hy- drogen driven off by heat will carry about 300 pounds of carbon in combination with it, making 400 pounds, or nearly 10,000 cubic feet of carburetted hydrogen gas. But still 1,300 pounds of carbon (65 per cent, of the original coal) will be left, and, with the earthy matter, ashes, sulphur, etc., retained with it, the coke will weigh but about 1,850 or 1,400 pounds, — 67i to 70 per cent, of the original coal. The only proportions in which carbon and hydro- gen combine with air in combustion are these : For every pound of carbon (pure coke). Hi pounds (equal to 152 cubic feet) of air are required to com- bine intimately with it. For every pound of hydrogen, 35 pounds (equal to 457 cubic feet) of air are required to be similarly combined. Thus for every pound of carburetted hydrogen gas, being one-fourth pound of hydrogen and three-fourths of a pound of carbon, 17f pounds (equal to 228 cubic feet) of air are required to be combiued with it. These are the elements and their combining pro- portions that have to be dealt with in a locomotive FURNACE. For every 2,000 pounds of coal burned, the 400 pounds of carburetted hydrogen — the ‘‘gas” — 72 HAND-BOOK OF THE LOCOMOTIVE. require 91,200 cubic feet of atmospheric air at ordi- nary temperature, and the 1,300 pounds of solid car- bon require 197,600 cubic feet of air. Practically, the “ gas ” from a ton of ordinary bituminous coal re- quires 100,000 cubic feet of air for its combustion, while the remaining coke requires 200,000 feet. Thus the gaseous matter of the coal requires one-half as much air as is taken up by the solid coke. The heating value of any combustible is exactly proportional to the quantity of air with which it will combine in combustion. Hence hydrogen, which combines with three times the quantity of air (oxygen) which would be taken up by carbon, has, for equal weights, three times the heating value. Thus, the 100 pounds of pure hydrogen in a ton of coal have the same heating efficiency as that due to 300 pounds of the remaining carbon or pure coke. It will now be seen that complete combustion can- not produce smoke, since smoke contains a quantity of unburnt matter, and is in itself a proof of in- complete combustion. The products of perfect com- bustion are invisible — being for carbon and oxygen, carbonic acid ; and for hydrogen and oxygen, invisi- ble steam, which condenses into water. The admission of heated air to furnaces or fire- boxes of locomotives can be of no practical value, since for every 461° Fah. of heat added, its original bulk or volume is doubled ; trebled at 922° Fah. ; so that at 2305° Fah. the heated air in the interior HAND-BOOK OF THE LOCOMOTIVE. 73 of the furnace has six times its original volume. This makes it more unmanageable, and as its contained oxygen remains the same in weight, its mixture with the gas becomes more difficult, while, when mixed, it can do only the same work as before. Waste of Unbupnt Fuel. — This generally arises from the brittleness of the fuel, combined with want of care on the part of the fireman, by which cause the fuel is made to fall into small pieces, which es- cape between the grate-bars into the ash-pit, and are lost. It is almost impossible to estimate the loss of fuel occasioned by carelessness and bad firing, but the amount which is unavoidable, even with care and good firing, has been ascertained by experiment to range from 2} to 3 per cent, of the fuel consumed. Spontaneous Combustion. — A great deal has been said and written on the subject of spontaneous combustion, and the danger likely to result from allowing steam-pipes to come in contact with the wood-work in buildings ; but as the temperature of superheated steam only ranges from 800° to 500° Fah., it is only able to set fire to such substances as sulphur, gun-cotton, and nitro-glycerine. It is, per- haps, able to fire gunpowder, but certainly cannot ignite wood. It is only when dried wood, sawdust, or rags have been saturated by drying oil or other equivalents, that the temperature may be indefinitely raised, and 74 HAN^D-BOOK OF THE LOCOMOTIVE. finally reach 400° or 500° Fah., or until the point of inflammability is attained. This is caused by the oxidation of the oil and the agency of the air. Fire. — Fire is one of the elements which has always attracted a great deal of attention from natural philosophers, and many theories have been advanced to account for all the remarkable phenomena which accompany heat. Late investigations, however, have proved that combustion is the result of chemical changes in bodies. TABLE SHOWING THE TOTAL HEAT OF COMBUSTION OF VARIOUS FUELS. SORT OF FUEL. Equivalent in pure carbon. Evaporative power in lbs. water from 212° Fah. Total heat of combustion in lbs. water heated 1° Fah. Charcoal 0.93 14.00 13500 Charred peat 0.80 12.00 11600 Coke — good 0.94 14.00 13620 “ mean 0.88 13.20 12760 bad 0.82 12.30 11890 COAL. Anthracite 1.05 15.75 15225 Hard bituminous — hardest. 1.06 15.90 15370 ‘‘ softest.. 0.95 14.25 13775 Cooking coal 1.07 16.00 15837 Canning coal 1.04 15.60 15080 Long flaming splint coal.... 0.91 13.65 13195 Lignite 0.81 12.15 11745 PEAT. Perfectly air-dry 0.66 10.00 9660 Containing 25 per ct. water 7.25 7000 WOOD. Perfectly air-dry 0.50 7.50 7245 Containing 20 per ct. water 5.80 5600 filAOT-BOOK OF THE LOCOMOTIVE. J^- 75 TABLE or TEMPERATURES REQUIRED FOR THE IGNITION OP DIFFERENT COMBUSTIBLE SUBSTANCES. SUBSTANCES. Tempera- ture of Ignition. RKM.4BKS. Phosphorus 140° Melts at 112°. Bisulphide of carbon vapor 300° Melts at 130°. Fulrainatins: Powder 374° Used in percussion caps. Fulminate of Mercury 392° According to Legue and Equal ])arts of chlorate of potash and sulphur 395° Champion. Sulphur 400° Melts, 239° ; boils, 570°. According to Legue and Gun-cotton 428° Nitro-glvcerine 494° Champion. u u tt Hi He -powder 550° iC it Gunpowder, coarse 563° il it tl Picrate of mercury, lead or iron 565° a it a Picrate powder for torpe- does 570° it tt it Picrate powder for muskets 576° Charcoal, the most inflam- tt tt tt mable willow used for gunpowder 580° According to Pelouse and Charcoal made by distill- ing wood at 500° 660° Fremy. tt tt tt Charcoal made at 600°.... 700° tt tt tt Picrate powder for cannon 716° Very dry wood, pine 800° oak 900° Charcoal made at 800°.... 900° It will be seen by the above table that the most combustible substances generally considered very dangerous, will only ignite by heat alone at a high temperature, so that for their prompt ignition it re- quires the actual contact of a spark. 76 HAND-BOOK OF THE LOCOMOTIVE. GASES. All substances, whether animal, vegetable, or min- eral, consisting of carbon, hydrogen, and oxygen, when exposed to a red heat, produce various inflam- mable elastic fluids, capable of furnishing artificial light. We perceive the evolution of this elastic fluid during the combustion of coal in a common fire. Bituminous coal, when heated to a certain degree, swells and kindles and frequently emits remarkably bright streams of flame, and after a certain period these appearances cease, and the coal glows with a red light. The flame produced from coal, oil, wax, tallow, or other bodies which are composed of carbon and hy- drogen, proceeds from the production of carburetted hydrogen gas, evolved from the combustible body when in an ignited state. If coal, instead of being burnt in the way now stated, is submitted to a temperature of ignition in close vessels, all its immediate constituent parts may be collected. The bituminous part is distilled over in the form of coal-tar, etc., and a large quantity of an aqueous fluid is disengaged at the same time, mixed with a portion of essential oil and various ammoni- acal salts. A large quantity of carburetted hydrogen, carbonic oxide, carbonic acid, and sulphuretted hydrogen also make their appearance, together with small quantities UA.ND-BOOK OF THE LOCOMOTIVE. 77 of cyanogen, nitrogen, and free hydrogen ; and the fixed base of the coal alone remains behind in the distillatory apparatus, in the form of a carbonaceous substance called coke. An analysis of the coal is thus effected by the process of destructive distillation. Hydrogen. — Hydrogen is the lightest of all known gases, its specific gravity being only 0.06896, air being 1. This gas is colorless, and when perfectly pure, inodorous. It has a powerful afilnity for oxy- gen, and is therefore emii^mtly combustible. Intense heat is developed by the combustion of hydrogen in oxygen gas, and but little light. Carbon. — Carbon is well known under the form of coke, charcoal, lamp-black, etc. It is one of the principal constituents of all varieties of coal, and is the basis of the illuminating gases. Carbonic oxide is a colorless and inodorous gas, rather lighter than common air, having a specific gravity of 0.9727, is sparingly absorbed by water, and does not precipitate lime-water. It is inflammable, burning with a blue flame ; the product of its combustion is carbonic acid. Carbon unites with hydrogen in many proportions, and many of these compounds are produced during the distillation of coal ; but the only two of importance are carburetted hydrogen and olefiant gas. Carburetted Hydrogen. — Carburetted hydrogen is abundantly formed in nature, in stagnant pools, ditches, etc., wherever vegetables are undergoing the process of putrefaction ; it also forms the greater part 78 HAND-BOOK OF THE LOCOMOTIVE. of the gas obtained from coal. Carburetted hydro- gen consists of iOO volumes of vapor of carbon, and 200 of hydrogen. It is colorless and almost inodor- ous ; it is not dissolved to any extent by water, and is much lighter than atmospheric air, its density being 0.5527. It is very inflammable, burning with • a strong yellow flame. The products of its combus- tion are carbonic acid and water. Carburetted hydrogen, or coal-gas, when freed from the obnoxious foreign gases, may be propelled in streams out of small apertures, which, when lighted, * form jets of flame, which are called gas-lights. Olefiant Gas. — Olefiant gas is a product of the distillation of oil, resin, and also of coal, when the process is well conducted. It is colorless, tasteless, and without smell when pure. Water dissolves about one-eighth of its bulk of this gas. It is formed of two volumes of hydrogen, and two of the vapor of carbon condensed into one volume. Olefiant gas burns with an intense white light, and requires a larger portion of oxygen for its combustion, one volume of the gas requiring not less than three volumes of pure oxygen, or fifteen volumes of atmos- pheric air for decomposition. The products of the combustion are water and carbonic acid. Nitrogen. — Nitrogen is one of the constituents of coal. It has the properties of extinguishing burning bodies, and is not absorbed by water; its specific gravity is 0.9760, being lighter than common air, of which it forms a constituent part. HAND-BOOK OF THE LOCOMOTIVE. 79 Liquefaction of Gases. — Many of the gases have already been brought into the liquid state by the conjoint agency of cold and compression, and all of them are probably susceptible of a similar reduction by the use of means sufficiently powerful for the re- quired end. They must consequently be regarded as the super- heated steams or vapors of the liquids into which they are compressed. Compression and Dilatation of Gases. — When a gas or vapor is compressed into half its original bulk, its pressure is double ; when compressed into a third of its original bulk, its pressure is treble ; when com- pressed into a fourth of its original bulk, its pressure is quadrupled ; and generally the pressure varies in- versely as the bulk into which the gas is compressed. So in like manner if the volume be doubled, the pressure is made one-half of what it was before — the pressure being in every case reckoned from 0, or from a perfect vacuum. Thus, if we take the average pressure of the atmos- phere at 14.7 pounds on the square inch, a cubic foot of air, if suffered to expand into twice its bulk by being pla(*,ed in a vacuum measuring two cubic feet, will have a pressure of 7.35 pounds above a perfect vacuum, and also of 7.35 pounds below the atmos- pheric pressure ; whereas, if the cubic foot be com- pressed into a space of half a cubic foot, the pressure will become 29.4 pounds above a perfect vacuum, and 14.7 pounds above the atmospheric pressure. 80 HAND-BOOK OF THE LOCOMOTIVE. The specific gravity of any one gas to that of an- other will not exactly conform to the same ratio under different degrees of heat and other pressures of the atmosphere. STEAM. The elastic fluid into which water is converted by the continued application of heat. All liquids whatever, when exposed to sufficiently high temperature, are converted into vapor. The mechanical properties of vapor are similar to those of gases in general. The property which is most important to be considered, in the case of steam, is the elastic pressure. When a vapor or gas is contained in a close vessel, the inner surface of the vessel will sustain a pressure arising from the elasticity of the fluid. This pressure is produced by the mutual repulsion of the particles, which gives them a tendency to fly asunder, and causes the mass of the fluid to exert a force tending to burst any vessel within which it is confined. This pressure is uniformly diffused over every part of the surface of the vessel in which such a fluid is contained ; it is to this quality that all the mechanical power of steam is due. Steam might be said to be the result of a combi- nation of water with a certain amount of heat, and the expansive force of steam arises from the absence of cohesion between and among the particles of water. HAND-BOOK OF THE LOCOMOTIVE. 81 Heat universally expands all matter within its in- fluence, whether solid or fluid. But in a solid body it has the cohesion of the particles to overcome, and this so circumscribes its effect that in cast-iron, for instance, a rate of temperature above the freezing- point sufficient to melt it causes an extension of only about one-eighth of an inch in a foot. With water, however, a temperature of 212°, or 180° above the freezing-point (and which is far from a red heat), con- verts it into steam of 1,700 times its original bulk or volume. Steam cannot mix with air while its pressure ex- ceeds that of the atmosphere, and it is this property, with that which makes the condition of a body de- pendent on its temperature, that explains the con- densing property of steam. In a cylinder once filled with steam of a pressure of 15 pounds or more to the square inch, all air is excluded. Now, as the existence of the steam depends on its temperature, by abstracting that temperature (which may be done by immersing the cylinder in cold water or cold air) the contained steam assumes the state due to the reduced temperature, and this state will be water. But one of the most noteworthy properties of steam is its latent or concealed heat. The latent heat of steam, though showing no effect on the ther- mometer, may be as easily known as the sensible or perceivable heat. F HAND-BOOK OF THE LOCOMOTIVE. To show this property of steam by experiment, place an indefinite amount of water in a closed ves- sel, and let a pipe, proceeding from its upper part, communicate with another vessel, which should be open, and, for convenience of illustration, shall con- tain just 5.37 pounds of water at 32°, or just freezing. The pipe from the closed vessel must reach nearly to the bottom of the open one. By boiling the water contained in the first vessel until steam enough has passed through the pipe to raise the water in the open vessel to the boiling-point (212° Fah.),we shall find the weight of the water contained by the latter to be pounds. Now, this addition of one pound to its weight has resulted solely from the admission of steam to it, and this pound of steam, therefore, re- taining its own temperature of 212°, has raised 5.37 pounds of water 180°, or an equivalent to 966.6°, and including its own temperature, we have 1178.6°^ which it must have possessed at first. The sum of the latent and sensible heat of steam is in all cases nearly constant, and does not vary much from 1200°. The elasticity of steam increases with an increase in the temperature applied, but not in the same ratio. If steam is generated from water at a tempera- ture which gives it the same pressure as the atmos- phere, an additional temperature of 38° will give it the pressure of two atmospheres ; a still further addi- tion of 42° gives it the tension of four atmospheres • HAND-BOOK OF THE LOCOMOTIVE. 83 and with each successive addition of temperature of between 40^^ and 50° the pressure becomes doubled. An established relation must exist between the temperature and elasticity of steam ; in other words, water at 212° Fah. must be under the pressure of the steam naturally resulting from that temperature, and so at any other temperature. If this natural pressure on the surface of the water be removed without a corresponding reduction in the temperature, a violent ebullition of the water is the immediate result. Another result attending formation of steam is, that when an engine is in operation and working off a proper supply of steam, the water level in the boiler artificially rises, and shows by the gauge- cocks a supply greater than that which really exists. As the pressure of steam is increased the sensible heat is augmented, and the latent heat undergoes a corresponding diminution, and vice versa. The sum of the sensible and latent heat is, in fact, a constant quantity ; the one being always increased at the ex- pense of the other. It has been shown that in converting water at 82° of temperature, and under a pressure of 15 pounds per square inch, it was necessary first to give it 180° additional sensible heat, and afterwards 966.6° of la- tent heat, the total heat imparted to it being 1146.6°. Such, then, is the actual quantity of heat which must be imparted to ice-cold water to convert it into 84 HAND-BOOK OF THE LOCOMOTIVE. steam. The actual temperature to which water would be raised by the heat necessary to evaporate it, if its evaporation could be prevented by con- fining it in a close vessel, will be found by adding 32° to 1146.6°. It may, therefore, be stated that the heat necessary for the evaporation of ice-cold water is as much as would raise it to the temperature of 1178.6°, if its evaporation were prevented. If tne temperature of red-hot iron be, as it is sup- posed, 800° or 900°, and that all bodies become in- candescent at the same temperature, it follows that to evaporate water it is necessary to impart to it 400° more heat than would be suflicient to render it red-hot, if its evaporation were prevented. It has been asserted, in some scientific works, that by mere mechanical compression, steam will be con- verted into water. This is, however, an error, since steam, in whatever state it may exist, must possess at least 212° of heat ; and as this quantity of heat is suflicient to maintain it in the vaporous form under whatever pressure it may be placed, it is clear that no compression or increase of pressure can diminish the actual quantity of heat contained in the steam, and it cannot, therefore, convert any portion of the steam into power. Steam, by mechanical pressure, if forced into a diminished volume, will undergo an augmentation both of temperature and pressure, the increase of HAND-BOOK OF THE LOCOMOTIVE. 85 temperature being greater than tbe diminution of volume; in fact, any change of volume which it undergoes will be attended with the change of temperature and pressure indicated in the table on pages 91, 92. The steam, after its volume has been changed, will assume exactly the pressure and temperature which it would have in the same volume if it were immediately evolved from water. Now, let us suppose a cubic inch of water con- verted into steam under a pressure of 15 pounds per square inch, and the temperature of 212°. Then let its volume be reduced by compression in the proportion of 1700 to 930. When so reduced, its temperature will be found to have risen from 15 pounds per square inch to 29 i pounds per square inch ; but this is exactly the state as to pressure, tem- perature, and density the steam would be in if it were immediately raised from water under the pressure of 29 i pounds per square inch. It appears, therefore, that in whatever manner, after evaporation, the den- sity of steam be changed, whether by expansion or contraction, it will still remain the same as if it were immediately raised from water in its actual state. The circumstance which has given rise to the erroneous notion that mere mechanical compression will produce a condensation of steam, is that the vessel in which steam is contained must necessarily have the same temperature as the steam itself. 8 86 HAND-BOOK OF THE LOCOMOTIVE. Water while passing into steam suffers a great enlargement of volume; steam, on the other, hand, in being converted into water, undergoes a correspond- ing diminution of volume. It has been seen that a cubic inch of water, evaporated at the temperature of 212"^, swells into 1700 cubic inches of steam. It follows, therefore, that if a closed vessel, containing 1700 cubic inches of such steam, be exposed to cold sufBcient to take from the steam all its latent heat, the steam will be reconverted into water, and will shrink into its original dimensions, and will leave the remainder of the vessel a vacuum. This property of steam has supplied the means, in practical mechanics, of obtaining that amount of mechanical power which the properties of the atmos- phere confer upon a vacuum. The temperature and pressure of steam produced by immediate evaporation, when it has received no heat, save that which it takes from the water, have a fixed relation one to the other. If this relation was known and expressed by a aathematical formula, the temperature might always be inferred from the pressure, or viee versa. But physical science has not yet supplied any principle by which such a formula can be deduced from any known properties of liquids. The same difiiculty which attends the establish- ment of a general formula expressing the relation between the temperatures and pressures of steam, HAND-BOOK OF THE LOCOMOTIVE. 87 also attends the determination of one expressing the relation between tlie pressure and the augmented volume into which the water expands by evapora- tion. In the preceding observations, steam has been con- sidered as receiving no heat except that which it takes from the water during the process of evapora- tion ; the amount of which, as has been shown, is 1146.6° more than the heat contained in ice-cold water. But steam, after having been formed from water by evaporation, may, like all other material substances, receive an accession of heat from any external source, and its temperature may thereby be elevated. If the steam to which such additional heat is im- parted be so confined as to be incapable of enlarging its dimensions, the efiect produced upon it by the in- crease of temperature will be an increase of pressure. ^ But if, on the other hand, it be confined under a given pressure, with power to enlarge its volume, subject to the preservation of that pressure, as would be the case if it were contained in a cylinder under a movable piston loaded with a given pressure, then the efiect of the augmented temperature will be, not an increase of pressure, but an increase of volume ; and the increase of volume in this latter case will be in exactly the same proportion as the increase of pressure in the former case. These efiects of elevated temperature are common, not only to the vapors of all liquids, but also to all 88 HAND-BOOK OF THE LOCOMOTIVE. permanent gases ; but, what is much more remark- able, the numerical amount of the augmentation of pressure or volume produced by a given increase of temperature is the same for all vapors and gases. If the pressure which any gas or vapor would have, were it reduced to the temperature of melting ice, be expressed by 100 , 000 , the pressure which it will re- ceive for every degree of temperature by which it is raised will be expressed by 208 3 , or what amounts to the same, the additional pressure produced by each degree of temperature will be the 480th part of its pressure at the temperature of melting ice. Steam which thus receives additional heat after its separation from the water from which it is evolved has been called superheated steam, to distinguish it from common steam, which is that usually employed in steam engines. Steam of atmospheric pressure occupies 1642 times the volume of the water from which it is raised, and as a cubic foot of water weighs 62.4 pounds, a cubic foot of steam of atmospheric pressure weighs about .038 pound. In order to exert a pressure by its mere dead weight of 14.7 pounds per square inch, such steam of uniform density would have to stand at a height of 10 J miles. Superheated steam admits of losing a part of its heat without suffering partial condensation ; but common steam is always partially condensed, if any porti(fn of heat be withdrawn from it. HAND-BOOK OF THE LOCOMOTIVE. 89 TABLE SHOWING THE VELOCITY WITH WHICH STEAM OF DIFFEKENT PRESSURES WILL FLOW INTO THE ATMOSPHERE OR INTO STEAM OF LOWER PRESSURE. Pressure above the atmosphere. Velocity of escape per second. Pressure above the atmosphere. Velocity of escape per second. Pounds. Feet. Pounds. Feet. 1 540 50 1,736 2 698 60 1,777 3 814 70 1,810 4 905 80 1,835 5 981 90 1,857 10 1,232 100 1,875 20 1,476 110 1,889 30 1,601 120 1,900 40 1,681 130 1,909 One cubic foot of steam at a pressure of 15 pounds per square inch weighs .0367 pound. Five cubic feet of steam at a pressure of 75 pounds per square inch weighs 1 pound. Seventy-five cubic feet of steam at a pressure of 140 pounds per square inch weighs 26 pounds. Rule for finding the Superficial Feet of Steam-pipe required to Heat any Building ivith Steam, One superficial foot of steam-pipe to 6 superficial feet of glass in the windows, or 1 superficial foot of steam-pipe for every 100 square feet of wall, roof or ceiling, or 1 square foot of steam-pipe to 80 cubic feet 8 * 90 HA-ND-BOOK OF THE LOCOMOTIVE. of space ; 1 cubic foot of boiler is required for every 1,500 cubic feet of space to be warmed. The following table shows that the saving of fuel is in proportion to the increase of pressure — the ad- vantage of generating and using high-pressure steam is thereby made apparent. The table also shows that the last 10 pounds of additional pressure only requires four degrees of heat to raise it ; whereas the first 10 pounds of pressure above the atmosphere re- quires 29 additional degrees of heat to raise it a dif- ference of 25 degrees. Hence a small accession of heat at a high tempera- ture produces an increase of elastic force; and a small abstraction of heat reduces its bulk, by the application of cold in the ratio of its density; prov- ing the advantage of clothing cylinders, steam-pipes, boilers, etc., with a non-conductor of heat or cold — a sure saving of fuel, where adopted, and more par- ticularly required where high-pressure steam is used. Steam, at any given pressure, always stands at a certain temperature, which is termed the tempera- ture due to the pressure.” Steam follows very nearly the same law that all other gaseous bodies are sub- ject to in acquiring additional degrees of heat. The law is, briefly, as follows : That all gaseous bodies expand equally for equal additions of temperature ; and that the progressive rate of expansion is equal for equal increments of temj^eratui e. HAND-BOOK OF THE LOCOMOTIVE, 91 TABLE SHOWING THE TEMPERATURE OF STEAM AT DIFFERENT PRES- SURES FROM 1 POUND PER SQUARE INCH TO 240 POUNDS, AND THE QUANTITY OF STEAM PRODUCED FROM A CUBIC INCH OF WATER, ACCORDING TO PRESSURE. Total pressure of steam in pounds per square inch. Corresponding tem- perature of steam to 1 pressure. Cubic inches of steam from a cubic inch of water ac- cording to pressure. Total pressure of steam in pounds per square inch. Corresponding tem- perature of steam to pressure. Cubic inches of steam from a cubic inch of water ac- cording to pressure 1 102.9 20868 28 247.6 941 2 126.1 10874 29 249.6 911 3 141.0 7437 30 251.6 883 4 152.3 5685 31 253.6 857 5 161.4 4617 32 255.5 833 6 169.2 3897 33 257.3 810 7 175.9 3376 34 259.1 788 8 182.0 2983 35 260.9 767 9 187.4 2674 36 262.6 748 10 192.4 2426 37 264.3 729 11 197.0 2221 38 265.9 712 12 201.3 2050 39 267.5 695 13 205.3 1904 40 269.1 679 14 209.1 1778 41 270.6 664 15 212.8 1669 42 272.1 649 16 216.3 1573 43 273.6 635 17 219.6 -1488 44 275.0 622 18 222.7 1411 ' 45 276.4 610 19 225.6 1343 46 277.8 598 20 228.5 1281 47 279.2 586 21 231.2 1225 48 280.5 575 22 233.8 1174 49 281.9 564 23 236.3 1127 50 283.2 554 24 238.7 1084 51 284.4 544 25 241.0 1044 52 285.7 534 26 243.3 1007 53 286.9 525 27 245.5 973 54 288.1 516 92 HAND-BOOK OF THE LOCOMOTISTE. TABLE— {Continued) SHOWING THE TEMPERATUKE OF STEAM, ETC. Total pressure of steam in pounds per square inch. ! Corresponding tem- perature of steam to pressure. Cubic inches of steam from a cubic inch of water ac- cording to pressure. Total pressure of steam in pounds per square inch. Corresponding tem- perature of steam to pressure. Cubic inches of steam from a cubic inch of water ac- cording to pressure. 55 289.3 508 85 320.1 342 56 290.5 500 86 321.0 339 57 291.7 492 87 321.8 335 58 292.9 484 88 322.6 832 59 294.2 477 89 323.5 328 60 295.6 470 90 324.3 325 61 296.9 463 91 325.1 322 62 298.1 456 92 325.9 319 63 299.2 449 93 326.7 316 64 300.3 443 94 327.5 313 65 301.3 437. 95 328.2 310 66 302.4 431 96 329.0 307 67 303.4 425 97 329.8 304 68 304.4 419 98 330.5 301 69 305.4 414 99 331.3 298 70 306.4 408 100 332.0 295 71 807.4 403 110 339.2 271 72 308.4 398 120 345.8 251 73 309.4 393 130 352.1 233 74 310.3 388 140 357.9 218 75 311.2 383 150 363.4 205 76 312.2 379 160 368.7 193 77 313.1 374 170 373.6 183 78 314.0 370 180 378.4 174 79 314.9 366 190 382.9 166 80 315.8 362 200 387.3 158 81 316.7 358 210 391.5 151 82 817.6 354 220 395.5 145 83 318.4 350 230 399.4 140 84 319.3 346 240 403.1 134 HAND-BOOK OF THE LOCOMOTIVE 94 HAND-BOOK OF THE LOCOMOTIVE. HORSE-POWER OF STEAM-ENGINES. The power which a steam-engine can furnish is generally expressed in “ horse-power.” It will, therefore, be necessary to make a brief explanation of what is meant by the term “ horse-power,” and how it has happened that the power of a steam- engine is thus expressed in reference to that of horses. Prior to the introduction of the steam-engine, horses were very generally used to furnish power to perform various kinds of work, and especially the work of pumping water out of mines, raising coal, etc. For such purposes, several horses working together were required. Thus, to work the pumps of a certain mine, five, six, seven, or some ^ther number of horses were found necessary. When it was proposed to substitute the new power of steam, the proposal naturally took the form of furnishing a steam-engine capable of doing the work of the number of horses used at the same time. Hence, naturally followed the usage of stating the number of horses which a particular engine was equal to, that is, its ‘‘ horse-power.” But as the two powers were only alike in their equal capacity to do the same work, it became necessary to refer in both powers to some work of a similar character which could be made the basis of comparison. Of this character was the work of raising a weight perpendicularly. HAND-BOOK OF THE LOCOMOTIVE. 95 A certain number of borses could raise a certain weight, as of coal out of a coal mine, at a certain speed; a steam-engine, of certain dimensions and supply of steam, could raise the same weight at the same speed. Thus, the weight raised at a known speed could be made the common measure of the two powers. To use the common measure it was necessary to know what was the power of one horse in raising a weight at a known speed. By observation and experiment it was ascertained that, referring to the average of horses, the most ad- vantageous speed for work was at the rate of 2i miles per hour — that, at that rate, he could work 8 hours per day, raising perpendicularly from 100 to 150 pounds. The higher of these weights was taken by Watt, that is, 150 pounds at 2} miles per hour. But this fact can be expressed in another form : — 2J miles per hour is 220 feet per minute. So, the power of a horse was taken at 150 pounds, raised perpendicularly, at the rate of 220 feet per minute. This also can be expressed in another form: — The same power which will raise 150 pounds 220 feet high each minute, will raise 300 pounds 110 feet high each minute. 3,000 “ 11 33,000 ‘‘ 1 “ ‘‘ For in each case the total work done is the same, viz., same number of pounds raised one foot in one minute. HAND-BOOK OF THE LOCOMOTIVE. It will be clearly perceived that 33,000 pounds, raised at the rate of one foot high in a minute, is the equivalent of 150 pounds at the rate of 220 feet per minute (or 2i miles per hour) ; and it will be fully understood how it is that 33,000 pounds, raised at the rate of one foot per minute, expresses the power of one horse, and has been taken as the standard measure of power. It has thus happened that the mode of designating the power of a steam-engine has been by “ horse- power,” and that one horse -power, expressed in pounds raised, is a power that raises 33,000 pounds one foot each minute. This unit power is now uni- versally received. Having a horse-power expressed in pounds raised, it was easy to state the power of a steam-engine in horse-power, which was done in the following manner : The force with which steam acts is usually ex- pressed in its pressure in pounds on each square inch. The piston of a high-pressure steam-engine is under the action of the pressure of steam from the boiler, on one side of the piston, and of the back action of the pressure due to the discharging steam, on the other side. The Power of the Engine. — The difference between the two pressures is the effective pressure on the piston ; and the power developed by the motion of the piston, under this pressure, will be according to the number of square inches acted on and the speed HAND-BOOK OF THE LOCOMOTIVE. 97 per minute which the piston is assumed to move* Thus, let the number of square inches in the area of the piston of a steam-engine be 100, the effec- tive pressure on each square inch be 60 pounds, and the movement of the piston be at the rate of 300 feet per minute, then the total effective pressure on the piston will be 100x60 = 6,000 pounds, and the movement being 300 feet per minute, the piston will move with a power equal to raising 1,800,000 pounds one foot high each minute, (as 6,000x300 is 1,800,000,) and as each 33,000 pounds raised one foot high is one-horse power, then the power of the engine is 54-horse. ‘ Now, if this power is used to do work, a part of it will be expended in overcoming the friction of the parts of the engine and of the machinery through which the power is transmitted to perform the work. The calculation made refers to the total power de- veloped by the movement of the piston under the pressure of steam. The number of feet travelled by the piston each minute is known from the length of the stroke of the piston in feet, and number of revolutions of engine per minute, there being two strokes of the piston for each revolution of the engine. When these three facts are known, the power of an engine can be readily and accurately ascertained, and it is evident that, without the knowledge of each of the facts, viz., square inches of piston, effective pressure 9 G 98 HAND-BOOK OF THE LOCOMOTIVE. on each square inch, and movement of piston per minute, the power cannot be known. If it becomes necessary to state the power of an engine, then the three facts named above, viz., num- ber of square inches of piston, effective pressure per square inch per stroke of piston, and speed of piston must be known or assumed, and when known or as sumed, the horse -power can in that case be ascer- tained, as explained above. There are three kinds of horse-power referred to in connection with the steam-engine — nominal, indi- cated, and actual. The nominal horse-power is a power that raises 33,000 pounds one foot high each minute, or 150 pounds 220 feet high in the same space of time. The indicated horse-power designates the total unbalanced power of an engine employed in over- coming the combined resistance of friction and the load. Hence it equals the quantity of work per^* formed by the steam in one minute. The actual or net horse-power expresses the total available power of an engine, hence it equals the indicated horse-power less an amount expended in overcoming the friction. The latter has two compo- nents, viz., the power required to run the engine, detached from its load, at the normal speed, and that required when it is connected with its load. For instance, if a person desires an engine to drive ten machines, each requiring ten-horse power, the engine HAND-BOOK OF THE LOCOMOTIVE. should be of sufficient size to furnish one hundred net horse-power ; but to produce this would require about one hundred and fifteen indicated horse- power. Stationary Engines in the United States in 1870. — Whole number of stationary engines in the United States in 1870 was 40,191, with an aggregate horse- power of 1,215,711. Rule for finding the Horse-power of Stationary Engines, Multiply the area of the piston by the average pressure in pounds per square inch ; multiply this product by the travel of piston in feet per minute ; divide by 33,000, this will give the horse-power. EXAMPLE. Diameter of cylinder 12 12 144 7854 Area of piston 113.0976 Pressure, 70 ; average press., 50... 50 5654.880 Travel of piston in feet per min. 300 33,00 0)1696464.000 51. horse powei. It has been found in practice that the maximum pressure in the cylinders of steam-engines and loco- motives never exceeds | the boiler pressure. 100 HAND-BOOK OF THE LOCOMOTIVE. 2 - i -Ph .P ^ (M g ^ 3 ^ 2 oTS HAND-BOOK OF THE LOCOMOTIVE. 101 THE POWER OF THE LOCOMOTIVE. In estimating the power of a locomotive, the term horse-power is not generally used, as the difference between a stationary steam-engine and a locomotive is such that while the stationary engine raises its load, or overcomes any directly opposing resistance, with an effect due to its capacity of cylinder, the load of a locomotive is drawn, and its resistance must be adapted to the simple adhesion of the engine, which is the measure of friction between the tires of the driving-wheels and the surface of the rails. The power of the locomotive is measured in the moving force at the tread of the tires, and is called the traction force, and is equivalent to the load the locomotive could raise out of a pit by means of a rope passing over a pulley and attached to the circumfer- ence of the tire of one of the driving-wheels. The adhesive power of a locomotive is the power of the engine derived from the weight on its driving- wheels, and their friction or adhesion on the rails. But the adhesion varies with the weight on the drivers and the state of the rails. The tractive force of a locomotive is the power of the engine, derived from the pressure of steam on 9 * 102 HAND-BOOK OF THE LOCOMOTIVE. the piston, applied to the crank and radius of the wheels. Rule for finding the Horse-power of a Locomotive, Multiply the area of the piston by the pressure per square inch, which should be taken as i the boiler pressure ; multiply this product by the num- ber of revolutions per minute ; multiply this by twice the length of stroke in feet or inches ;* multiply this product by 2, and divide by 33,000 ; the result will be the power of the locomotive. EXAMPLE. Cylinder, 19 inches. Stroke, 24 Diameter of drivers, 54 inches. Eunning speed, 20 miles, per hour. Area of piston, 283.5 square inches. B^Uer pressure, 130 pounds per square inch. Maximum pressure in cylinders, 80 pounds. 283.5 X 80 X 4 X 124 X 2 33,000 681.6 horse-power. RULES FOR CALCULATING THE TRACTIVE POWER OF LOCOMOTIVES. Rule I. — Multiply the diameter of the cylinder in inches by itself; multiply the product by the If in inches they must be divided by 12. HAND-BOOK OF THE LOCOMOTIVE. 103 mean pressure of steam in the cylinder in pound? per square inch ; multiply this product by length of stroke in inches ; divide the product by the diame- ter of the wheels in inches. Kesult equals the trac- tive force at the rails. Rule 2. — To calculate the load which can he hauled by an engine on a level at a given speed, — Divide the tractive force, as per Eule 1, by the resistance in pounds per ton due to friction, imperfection of road, and winds. The quotient is the total load in tons, comprising the engine, tender, and train. Rules. — To calculate total resistance of engine y tender, and train at a given speed, due to friction, etc, — Square the speed in miles per hour, divide it by 171, and add 8 to the quotient. The result is the totdl resistance at the rails in pounds per ton weight. Rule 4. — To find the load a locomotive ^can haul at a given speed on a given incline, — Divide the trac- tive power of the engine in pounds by the resistance due to gravity on a given incline, added to resistance due to assumed velocity of train in pounds per ton ; the quotient, less the weight of the engine and tender, equals the load in tons the engine can haul on a given incline. Example, Rule I. — What is the tractive force of a locomotive 16 inch cylinder, 24 inch stioke, 4 feet drivers, mean pressure 80 pounda per square inch? 104 HAND-BOOK OF THE LOCOMOTIVE. Cylinder, 16 inches 16 16 96 16 Pressure in pounds, 80.. 256 80 Stroke, 24 inches 20480 24 81920 40960 Drivers 4 ft. or 48 in.... ..48)491520 10240 lbs. tractive force. 2000)10240 lbs. tractive force. 5/3 tons. Example, Rule 2. — What load can a locomotive, 16 inch cylinder, 24 inch stroke, 4 feet drivers, mean pressure 80 pounds, haul on a level at 30 miles per hour? Tractive force, obtained as in Rule 1, is 10240 lbs. Velocity per hour, 30 miles. 30 13.2 6)10240 30 772J load in tons 171 )900 Resistance in 5.26 lbs. per ton, 8 13.26 HAND-BOOK OF THE LOCOMOTIVE. 105 Example, Rule 4. — What load can a locomotive, 16 inch cylinder, 24 inch stroke, 4 feet drivers, mean pressure 80 pounds, haul on a grade of 132 feet to the mile at 30 miles per hour ? Tractive force, obtained as in Kule 1 10240 lbs Eesistance, in lbs. per ton, due to grav- ity (see Table of Gradients) 56 Eesistance, in lbs. per ton, due to fric- tion, winds, etc 13.26 Total resistance in lbs. per ton 69.26 Tractive force divided by total resist- 1 69.26)10240.00 ance equals load, in tons, engine > 7! 147.83 can haul, less engine and tender...] Weight of engine and tender in tons 55.65 Load in tons 92.18 TABLE OF ORADIENTS. EISE IN FEET PEE. MILE AND EESISTANCE DUE TO GEAVITY ALONE. Feet. Feet. Feet. Feet. Feet. Feet. Feet. Eate of Gradient 20 25 30 35 40 45 50 Rise in feet per mile. 264 211 176 151 132 117 105 Resistance in pounds lbs. lbs. lbs. lbs. lbs. lbs. lbs. per ton of train 112 89i 74i 64 56 50 45 Besistancey due to gravity on any incline, in pounds per ton, of train, equals 2240 divided by rate of gradient. EXAMPLE. Gradient or rise of 1 foot in 20 feet 2240 gross ton 20)2240 Eesistance in lbs. per ton 112 106 HAND-BOOK OF THE LOCOMOTIVE. The power of an engine may be roughly computed by calling it equal to ^ of the weight on the driving- wheels, when the rails are wet or perfectly dry. Dampness or grease on the rails lessens the adhesive power of locomotives, as it is well known that the adhesion of engines is less in the neighborhood of depots and stations than it is out on the road. This arises from the quantity of oil that finds its way from the locomotives to the rails at oiling stations. Adhesive Power of Locomotives per ton of Load on tlu^ Driving-wheels, When rails are dry 600 lbs. per ton. ‘‘ wet 550 “ “ ‘‘ ‘‘ damp 450 ‘‘ ‘‘ Foggy weather 300 “ ‘‘ ‘‘ Ice or snowy weather 200 “ “ “ Rule for finding the Power of a Locomotive, Cylinder Stroke Eunning speed Steam pressure /in boiler Maximum pressure in cylinder Revolutions Area of piston 18 inches. 22 20 miles per hour. 125 lbs. per square inch. 60 lbs. per square inch. 125 per minute, 20 miles per hour. 254.4 square inches. 254.4 X 60 X 44 X 125 X 2 33,000 X 12 = 424 horse power. HAND-BOOK OF THE LOCOMOTIVE. 107 PROPORTIONS OP LOCOMOTIVES ACCORDING TO BEST MODERN PRACTICE. Diameter of cylinders .... 9 inches. Length of stroke .... 16 Diameter of drivers . 36 Wheel-base . 6ft. 6 Capacity of tank .... . 250 gallons. Weight of Engine in Working Order, 25,000 pounds. LOAD, In addition to Weight of Engine, On a level . 565 gross tons “ 20 feet grade per mile . . 265 « 40 ‘‘ « « , , . 170 ‘‘ « 60 “ « « , ^ . 125 ‘‘ « 80 “ « « , , . 100 o o . 80 Diameters of cylinders . . 10 inches. Length of stroke .... 20 ‘‘ Diameter of drivers 54 “ Four-wheeled Truck with centre-hearing Bolster, Diameter of wheels ... 24 inches. Wheel-base . ... 16ft. 3^ “ Capacity of tank . ... 900 gallons. Weight of Engine in Working Order, On drivers 23,000 pounds, “ trucks 15,000 “ ti Total weight of engine . . 38,000 108 HAND-BOOK OF THE LOCOMOTIVE. LOAD, In addition to Engine and Tender, On a level .... . 550 gross tons. ‘‘ 20 feet grade per mile 250 « 40 “ 160 ‘‘ “ 60 “ “ “ 115 “ « gQ « « 85 O O 65 Diameter of cylinders . 11 inches. Length of stroke 16 Diameter of drivers , 36 “ Two-wheeled Truck with Swing Bolster and Radius bar. Diameter of wheels . . 24 inches. Wheel-base .... . lift. 3 inches. Kigid wheel-base . 4‘‘ 8 ‘‘ Capacity of tank .... 400 gallons. Weight of Engine in Worhing Order, On drivers 35,000 pounds. ‘‘ truck 5,000 ‘‘ Total weight of engine . . . 40,000 LOAD, In addition to Weight of Engine, On a level ‘‘ 20 feet grade per mile a 40 t( (( (( U 0Q « « « « gQ u « U « 100 “ « 785 gross tong 370 240 ‘‘ 175 “ 135 110 '' HAND-BOOK OF THE LOCOMOTIVE. 109 Diameter of cylinders ... 12 inches. Length of stroke .... 22 ‘‘ Diameter of drivers . . . . 54 to 60 “ Four-wheeled Truck with centre-hearing Bolster, Diameter of wheels . . . . 24 to 26 inches. Wheel-base 18 ft. 1 “ Tender on two four-wheeled Trwjcs, Capacity of tank . . . . 1200 gallons. Weight of Engine in Working Order, On drivers 28,000 pounds. “ truck 16,000 Total weight of engine . . . 44,000 “ LOAD, ' In addition to Engine and Tender, On a level . . • . . 665 gross tons. U 20 feet grade per mile 305 U 40 « u 190 ii 60 ‘‘ a tt 135 « u 80 u (C 100 n 100 “ it 75 Diameter of cylinders .... 13 inches. Length of stroke . . . . . 22 to 24 “ Diameter of drivers . . . . 56 to 66 “ Four-wheeled centre-hearing Trucks with Swing Bolster, Diameter of wheels . . . . 24 to 30 inches. AVheel-base 20 ft. IJ “ Rigid wheel-base (distance between driving-wheel centres) . . 6 “ 6 10 110 HAND-BOOK OF THE LOCOMOTIVE. Tender on two four-wheeled Trucks, Capacity of tank 1,400 gallona. Weight of Engine in Working Order, On drivers 30,000 pounds. On truck . . . . . . 20,000 “ Total weight of engine 50,000 LOAD, In addition to Engine and Tender, On a level ‘‘ 20 feet grade per mile << U U H iC (C 0Q i( (( (i (( (t gQ (C (( (( t( (( (( Ct (C (t Diameter of cylinders . Length of stroke . Diameter of drivers . 710 gross tons. . 325 . 200 . 140 . 105 . 80 . 14 inches. . 22 to 24 . 56 to 66 “ Four-wheeled centre-hearing Trucks with Swing Bolster, Diameter of wheels . . . . 24 to 30 inches. Wheel-base 20 ft. 7i Eigid wheel-base (distance between dri- ving-wheel centres) . . . . 7 “ Tender on two four-wheeled Trucks, Capacity of tank 1,600 gallons. Weight of Engine in Working Order, On drivers 35,000 pounds. On truck 20,000 “ Total weight of engine . . , 55,000 ** ha:nd-book of the locomotive. Ill LOAD, In addition to Engine and Tender, On a level 835 gross tons. t( 20 feet grade per mile . . 380 !4 40 « i( a u . 240 (f U 60 '' “ '' a . 170 a it 80 '' (( . 124 (( (( o o . 100 « Diameter of cylinders Length of stroke . Diameter of drivers 15 inches. 22 to 24 ‘‘ 56 to 66 Four-wheeled centre-bearing Trucks with Swing Bolster, Diameter of wheels . . . . 24 to 30 inches. Wheel-base 21 ft. 3 “ Bigid wheel-base (distance between dri- ving-wheel centres) . . . . 7 “ 8 Tender on two four-wheeled Trucks, Capacity of tank 1,800 gallons. Weight of Engine in Working Order, On drivers 39,000 pounds. On truck . . . . . . 21,000 ‘‘ Total weight of engine .... 60,000 ** LOAD, In addition to Engine and Tender, On a level 930 gross tons. 20 feet grade per mile . . . 430 ‘‘ « 40 « . a ^ ^ ^ 270 ‘‘ “ 60 190 “ u 80 '' . 140 ‘‘ «ioo « « « « ^ ^ ^ iiQ « 112 HAND-BOOK OF THE LOCOMOTIVE. Diameter of cylinders .... 16 inches Length of stroke 22 to 24 “ Driving Wheels, Bear and front pairs, with flanged tires . 5 J in. wide. Main pair, with plain tires , . . 6 Diameter of drivers . . . . 48 to 54 “ Four-wheeled centre-hearing Truck, with Swing Bolster, Diameter of wheels . . . . 24 to 26 inches Wheel-base 23 feet. Rigid wheel-base (distance between cen- tres of rear and front drivers) . . 12 feet 1 inch Tender on two four-wheeled Trucks, Capacity of tank 1,600 gallons. Weight of Engine in Working Order, On drivers . . . 51,000 pounds. On truck • • . 16,000 ‘‘ Total weight of engine LOAD, • . 67,000 In addition to Engine and Tender, On a level . • 1,230 gross tons. “ 20 feet grade, per mile . . 570 « a a (( it . 360 u 0Q u « a (( . 260 ‘‘ << 80 ‘‘ (( . 195 “ « 100 '' « “ te . 155 ‘‘ Diameter of cylind^ rs . 17 inches. Length of stroke , • • . 22 to 24 “ Diameter of drivers , , . 56 to 66 '' HAND-BOOK OF THE LOCOMOTIVE. 113 Four-wheeled centre-hearing Truck, with Swing Bolster, Diameter of wheels . . . . 24 to 30 inches. Wheel-base 22 ft. 6J ‘‘ Eigid wheel - base (distance between driving-wheel centres) ... 8 feet. Tender on two four-wheeled Trucks. Capacity of tank 2,000 gallons. Weight of Engine in Working Order. On drivers .... . . 45,000 pounds. On truck .... . 25,000 a Total v;eight of engine . . 70,000 u LOAD, In addition to Engine and Tender. On a level .... . 1,075 gross tons. 20 feet grade per mile . 495 {( it a u li . 310 a U 0Q il (( f( « . 220 u a gQ if a {( if . 165 <( a 200 << “ << << . 130 u PROPORTIONS OP DIFFERENT PARTS OP LO- COMOTIVES, ACCORDING TO BEST MODERN PRACTICE. In locomotive engines, the diameter of the cylinder varies less than in either stationary or marine en- gines. The range, with few exceptions, is between 10 and 20 inches. 10 * H 114 HAND-BOOK OF THE LOCOMOTIVE. Diameter of Cylinder. Diameter of Main Steam Pipe Diameter of Cylinder. Diameter of Main Steam Pipe Diameter of Cylinder. Diameter of Main Steam Pipe, 8 in. 41 in. 12 in. 5 in. 16 in. 6 in. 9 “ 4 “ 13 “ 5 17 6 10 “ “ 14 5 “ 18 “ 6 11 “ 4J “ 15 “ 6 “ 20 “ 6 Diameter of Cylinder. Diameter of Piston Rod. Valve Stems. Diameter of Cylinder. Diameter of Piston Rod. Valve Stems. 8 in. li in. f in. 15 in. 2J in. IJ in. 9 “ H " 7 U ■? 16 “ 2 JC. eng. 1 1 a 12^ 10 11 li “ 2 “ 1 “ n “ 16 » 17 “ 2iD.eng. 2i in. 1| “ 12 “ 2 14 “ 18 “ 3 “ 1 7 « -^8 13 14 “ 2i 2i n “ If “ 19 20 “ 3i 3i “ 2 “ Diameter of Cylinder. Diameter of Pump Plunger. 7 in. 1 in. 8 1 “ 9 14 “ 1 10 U “ 11 1 3 « 8 11 “ 15 . -*■8 Diameter of Cylinder. Diameter of Pump Plunger. 12 in. IJ in. 12 “ If “ 13 “ If “ 14 “ If “ 14 “ -17 it J-8 15 “ If Diameter of Cylinder. Diameter of Pump Plunger. 16 in. If in. 16 2 “ 17 “ 17 a 17 2 18 24 “ 20 24 “ Diameter of Cylinder. Diameter of Crank Pins. Diameter of Cylinder. Diameter of Crank Pins. Diameter of Cylinder. Diameter of Crank Pins. 7 in. ^ in. 12 in. 3 in. 17 in. 34 in. 8 2J 13 3i “ 17 “ 3| 9 2| “ 14 3i 18 “ 4 '' 10 ‘‘ 3 15 qi it 19 “ 44 11 3 16 34 “ 20 “ 4i « HAND-BOOK OF THE LOCOMOTIVE, 115 Diameter of Cylinder. Length of M’n Crank in Bearing. Diameter of Cylinder. Length of M’n Crank in Bearing. Diameter of Cylinder. Length of MainCrauk in Bearing 8 in. 2h in. 12 in. 3^ in. 16 in. 3f in. 9 ‘‘ 2| “ 13 “ 3i 17 4 “ 10 3 14 “ 3J 18 “ 4i 11 “ 3 15 3J 20 “ 4f-5 Diameter of Cylinder. Diameter of Eeverse Shaft Bearings. Diameter of Cylinder. Diameter of Eeverse Shaft Bearings. Diameter of Cylinder. Diameter of Eeverse Shaft Bearings. 8 in. li^ in. 12 in. 2 in. 16 in. 2 in. 9 n “ 13 2 17 2 “ 10 “ If 14 2 “ 18 “ 2 11 “ If 15 2 “ 20 2 “ Diameter of Cylinder. Depth of MainEods. Thick. Diameter of Cylinder. Depth of Main Eods. Thick. Front Back Front Back End. End. End. End. 8 in. 2 IJ in. 15 in. ^8 1^ in. 9 2 15 a ^ 8 16 “ 3 2i “ 10 2f 2^ If 17 3J 3 17 U ^8 11 “ 2i 2i 13. « -^4 18 3i 3 2 12 “ 21 2| 1i i( J-8 19 “ 4 31 2 “ 14 3 2| 17 if ^8 20 “ 4i 3i 2i Diameter of Cylinder. Diameter of Journals Driving Axles. Length of Journals. Diameter of Cylinder. Diameter of Journals Driving Axles. Length of Journals. 7 in. 8 “ 9 10 “ 11 12 13 “ 1 1 4 in. 4f “ 4f “ 4f “ 4i 5i “ 5i “ 4f in. ■ 5 5f “ 5J 5i 6f “ 6J 14 in. 15 16 16 17 18 20 6 in. 6J “ 7 “ 6 6 6i 6^ “ 6f in. 6f 8 7 “ 7 7i 7J 116 HAND-BOOK OF THE LOCOMOTIVE. Diameter of Cylinder. Steam-port. Exhaust-port. Bridges. 8 ViX # 7JXU 1 9 7iX i 7iXli 1 10 7iX f 7iXli i 11 10 XI 10 X2 ■§• 12 10 XI 10 X2 i 13 12 XU 12 X2J 1 14 13 XU 13 X2J 1 15 14 XU 14 X2J 1 16 16 XU 16 X2i 1 17 16 XU 16 X2i 1 18 17 XU 17 X2} 1 20 18 XU 18 X2i 1 TABLE SHOWING THE TRAVEL OF VALVE AND THE AMOUNT OF LAP AND LEAD FOR DIFFERENT POINTS OF CUT- OFF, AND THE DISTANCE THE STEAM FOLLOWS THE PISTON ON THE FORWARD MOTION. EXAMPLE. Size of Cylinder, 16X24 inches ; Travel of Valve, 5i inches ; Lap, J inch outside ; Line and Line inside ; Steam Ports, ISXiJ inches; Exhaust, inches. Distance Steam Cut-off. Lead. Travel of Valve. follows Piston, Forward Motion. 6 in. A 2f 16-1 9 “ A 2A 1711 12 “ i 2f 19tV 15 “ A ^ i 20 i 18 “ A 2Uf 24 “ A 23 i 1 HAKr-BOOK OF THE LOCOMOTIVE. 117 Average Proportions of Different Parts of Locomotives, Area of steam -ports equal to ^-rea of cylinder. Area of exhaust-port equal to | area of cylinder. Area of main steam-pipe from f to J area of cylinder. Diameter of piston-rods the diameter of cylinder. Diameter of crank-pin } the diameter of cylinder. Diameter of valve stems the diameter of cylinder. Diameter of pump-plunger J the diameter of cylinder. RULES. Rule. — To find the Size of the Steam-ports for Loco- motive Engines, — Multiply the square of the diameter of the cylinder by .078. The product is the proper size of the steam-ports in square inches. Rule. — To find the Area of Exhaust-ports. — Mul- tiply the square of the diameter of the cylinder in inches by .178. The product is the area of the educ- tion ports in square inches. Rule. — To find the Diameter of the Steam-pipe of Locomotive Engines. — Multiply the square of the diameter of the cylinder in inches by .03. The pro- duct is the diameter of the steam-pipe in inches. Rule. — To find the Diameter of the Piston-rod for Locomotive Engines. — Divide the diameter of the cylinder in inches by 6. The quotient is the diam- eter of the piston-rod in inches. Rule. — To find the Diameter of the Cranlc-pin for Locomotive Engines. — Multiply the diameter of the cylinder in inches by .234. The product is the di- ameter of the crank-pin in inches. il8 HAND-BOOK OF THE LOCOMOTIVE. Rule. — To find the Diameter of the Feed-pump Ram, — Multiply the square of the diameter of the cylinder in inches by .0083. The product is the di- ameter of the ram in inches. LOCOMOTIVE BUILDING. Though locomotive building has long ceased to be considered an art, yet it requires the utmost atten- tion in respect to general design, construction, and the selection of materials; and for this reason all the principal parts are made according to accurate drafts, templets, and gauges in their respective de- partments before being taken to the erecting shop to be united in the construction of the engine. CONSTRUCTION OP LOCOMOTIVES. The boiler is first placed horizontal on the construc- tion track, and levelled by the dome top. The cylinders are next placed under the front end of the boiler, with the smoke-box resting in the sad- dles of the cylinders. The cylinders are then levelled by their valve seats. Lines are now accurately drawn through the cen- tre of the cylinders to the back end of the boiler, and the frames set up temporarily according to the lines drawn through the cylinders. The frame gauges are next placed on the frames, for the purpose of holding them in their right posi- tion and proper distance apart. HAND-BOOK OF THE LOCOMOTIVE. 119 Lines are again drawn through the centre of the cylinders to the back end of the frame, for the pur- pose of determining if the frames are parallel at both ends, and with the cylinders. Straight-edges are now laid across the top of the frames, to determine whether the frames are level or not, and also if the distance from the top of the frame to the centres of the cylinders corresponds exactly. The distance between the frames and the shell of the boiler is next measured, to ascertain the thickness of the liners. The furnace-pads are then placed in position and marked, counter-sunk, or planed to correspond with the ends of the stay-bolts on the outside of the fur- nace sheet, and also to stand parallel with the outside of the frames. The cylinders are next bolted to the smoke-arch, and the frames to the cylinders. The foot-plate is now placed on the frame, at the back end of the boiler; also, the back furnace braces and cross-ties fitted, drilled, and bolted to their respective places. The waste-sheet is then attached to the waste of the boiler, and the guide-braces and guide-bearers made fast to the boiler and the frames. The guides, cross-heads and back-heads of cylin- ders are next put on, and the pistons inserted in the cylinders and keyed to the cross-heads. The smoke-box braces are then fitted and drilled, and the centre casting bolted to the smoke-box. 120 HAND-BOOK OF THE LOCOMOTIVE. The flues, steam-pipe, throttle-pipe, throttle-valve, and arch-pipes are next placed in the boiler, and the safety-valves and whistle-stand attached to the steam dome. The boiler is then put under steam for the purpose of determining if it leaks or needs caulking. Then the boiler, cylinders, and steam domes are lagged and jacketed. The frame is now jacked up, the driving-wheels placed in the pedestals, the boxes secured by means of keys and wedges, and the pedestal caps put on. The rocker boxes are next bolted to the frame, and the rocker shafts placed in their proper positions. The rockers and rocker boxes need to be adjusted with a great deal of accuracy, as any slight divergence of the rockers from correct lines would derange the whole valve gear. The reverse shaft is then fastened on the frame by means of clamps, and its proper place determined by accurate measurements from its centres to the centres of the rockers. The valves are then placed on their seats in the steam-chest, and the valve-yokes and valve-rods attached to the rocker-arms. The eccentric straps and eccentric rods are next attached to the links, and the link-block connected with the rocker. Then everything is ready to set the valves. HAND-BOOK OF THE LOCOMOTIVE. 121 SETTING THE VALVES OP LOCOMOTIVES. Setting the valves of locomotives is perhaps one of the most important duties the engineer has to under- take, involving, as it does, nicety of calculation and mechanical accuracy ; and as the circumstances of construction, valve gear, pressure, and work to be done varies, it will at once be apparent that no one uniform rule for valve setting can be laid down. Everything being ready to set the valves of the locomotive, the main rods are put on, and the driving- wheels blocked up until the centre of the driving- boxes are parallel with centre of the cylinders ; the wedges in the driving-boxes are then set up to pre- vent lost motion. A circle is next described on the hub of the driv- ing-wheel equal in diameter to the width of the straps on the main rods; a straight-edge is now placed on the strap, and the wheels moved forward until the position of the straight-edge on the top and bottom of the strap is parallel with the sides of the circle on the hub of the wheel. A centre-punch mark is then made on the frame, in which one point of a trammel-gauge is inserted, and with the other point a mark is described on the face of the tire of the driving-wheel. Another cen- tre-punch mark is made on the guide even with the end of the cross-head at its farthest travel. These marks represent the position of the crank and cross- 11 122 HAND-BOOK OF THE LOCOMOTIVE. head at full stroke, or when the crank is at the dead centre on the forward motion. ^ 'j TRAMMEL GAUGE. Now, if the engine is 24-inch stroke, the wheel is moved forward until the cross-head travels 12 inches from the centre-punch mark on the end of the guide. The point of the trammel-gauge is now inserted in the centre-punch mark on the frame, and another mark is described on the face of the tire of the driving-wheel ; these points represent the position of the crank and cross-head at half-stroke. The wheel is again turned forward until the dead centre is reached, or until the lines on the top and bottom of the strap correspond with the circle on the hub of the wheel ; here another mark is made on the guide at the end of the cross-head. At this point also another centre-punch mark is made on the frame, and with the tram a mark is described on the face of the tire as before. The wheel is then turned forward until the cross- head travels 12 inches from the last mark made on the guide. Then the point of the tram is inserted in the centre-punch mark on the frame, and another mark described on the face of the tire of the driving- wheel. Now, these four marks will represent the four centres of the wheel on that side. HAND-BOOK OF THE LOCOMOTIVE. 123 The wheel is next turned until the dead centre is reached on the forward motion, and the reverse lever dropped until the distance between the link-block and the end of the link is about t of an inch, or, in Other words, f between striking points. Should the lead be right at this point, the posi- tion of the reverse latch is marked on the quadrant ; but if more or less than the required amount, the adjustment is made by moving the eccentric and lengthening or shortening the eccentric rods by means of slotted holes at the point where the rods are connected with the straps. But it must be remem- bered that the lead is always adjusted by moving the eccentrics, and the dividing is effected by shortening or lengthening the rods. The wheel is moved forward again to the other centre, for the purpose of determining if the lead is right at that end of the stroke ; and if it should be found to be more or less, the adjustment is made as before by moving the eccentric, and the lengthening or shortening is done by the rods in the slotted holes. The wheel is again turned forward until the cross- head moves 12 inches, and the valve is at its farthest travel. The position of the reverse latch is marked on the quadrant at this point, which gives the full opening of the port when the link is in full gear. The intermediate points of cut-off are then marked on the quadrant, which, for an engine 24-inch stroke, are generally 6, 9, 12, 15, 18. 124 HAKD-BOOK OF THE LOCOMOTIVE. In setting the valves of locomotives, care must be taken to turn the wheel forward for the forward motion, and bach for the backward motion. The notches on the quadrant for the backward motion are determined in the same way as for the forward motion, but there is generally one more notch for the forward than for the back motion, for the reason that the forward motion is more used. The position of the out-notch is determined by moving the reverse lever until the valve is in the centre of its travel, of until the link-block is directly under the saddle. The eccentric straps are next taken off and the holes drilled for the bolts that form the permanent connection between the straps and the rods. The positions of the eccentrics on the driving-axles are next marked with a diamond-pointed chisel, the set- screws slackened, and the eccentrics moved out for the purpose of slotting the axles for the feathers. The feathers are next inserted in the axles, and the eccentrics forced back to the same position they occu- pied before being marked with the diamond-pointed chisel ; the forward eccentric being generally placed on the inside. The set-screws are now screwed down. The set-screws for the eccentrics of locomotives are generally concaved and case-hardened on the points. The eccentric straps and rods are next put on and connected with the links; after which the springs are mounted, all the minor details of construction and adjustment finished up, and the engine painted and made ready for the road. ll* The American locomotive, the last great crowning invention of the human intellect, has no peer for beauty of design, or in the performance of its work. 126 HAND-BOOK OF THE LOCOMOTIVE. DEAD WEIGHT OF LOCOMOTIVES. The idea of lessening the dead ” and increasing the paying ” weight of locomotives, by utilizing the weight of fuel and water, and the tanks for the same, early suggested itself to railroad mechanics. An ordinary eight-wheeled American locomotive, with four 5-feet driving-wheels, and 15x22 inch cylinders, weighs, in working order, about 58,000 pounds, of which about 36,000, or less than two-thirds, is carried on the driving-wheels. A four-wheeled switching engine, which weighs 18 tons, has all its weight on the driving-wheels, and consequently will draw as many cars as an eight-wheeled locomotive weighing 29 tons. The tender of such an engine will weigh 20,000 pounds empty, and will carry 1,800 gallons of water and three tons of coal, making a total weight of 41,000 pounds. And as the supply of fuel and water varies very much, the tank being sometimes full but very seldom empty, it would be about fair to count two-thirds of the water and coal as the average weight carried. Therefore the average weight of the tender will be 34,000 pounds, which, added to that on the truck of the engine, would make the total dead weight of the locomotive and tender 56,000 pounds. The great difficulty heretofore in the way of re- ducing the ‘‘dead weight” of locomotive engines, would seem to arise from the necessity of using large HAND-BOOK OF THE LOCOMOTIVE. 127 boilers, the value or efficiency of the engine being dependent upon its boiler capacity; and as large boilers must of necessity be accompanied by weight in proportion to their size, the theory of reduction of dead weight, in engines, seems to be reduced to two propositions, viz., lighter boilers or lighter parts. But as the nominal adhesion of the standard eight- wheel American engine is often insufficient as at present constructed, hence it follows that if the weight be materially reduced, a large proportion of the re- maining weight must be placed upon the driving- wheels. Various new systems and theories have been urged at different times with a view of lessening the ‘‘ dead ” and increasing the “paying^’ weight on railroads. Tank engines seem to offer the most practical solution of the problem involved in the reduction of dead weight, as the tender can be, to a certain extent, dis- pensed with, and the weight of the water and fuel utilized on the drivers. It is true that water and fuel stations would have to be arranged nearer each other than is usual with the present system of engine and tender. But it is claimed that the facility with which tank engines run backward or forward, thus dispensing with turn- tables, and saving the time ordinarily consumed in turning, would more than counterbalance the addi- tional expense incurred in the increase of the fuel and water stations. It is a fact not sufficiently borne ]28 HAND-BOOK OF THE LOCOMOTIVE. in mind that there is a good deal of unnecessary ex- pense involved in hauling large weights of fuel and water over long distances on tenders. The locomotive represented on page 125 was especially designed to overcome the evil above mentioned. By this plan .not only is all the weight of the boiler and machinery carried by the driving-wheels, but by extending the frame beyond the fire-box far enough to receive the tank, and placing a truck underneath to carry the weight of water and fuel, a long wheel-base is secured, which adjusts itself to the curvature of the track, while at the same time the whole weight of the engine and boiler is carried on the driving-wheels. By this means the galloping motion common in tank engines is obviated, and the steadiness of an ordinary eight- wheel locomotive is attained. The tank engine described in the above paragraph has been designed to run with its truck ahead ; and as one of the essential features of the plan is to carry the boiler and machinery, whose weight is permanent, on the driving-wheels, and the water and fuel, which are variable, on the truck, therefore, running the loco- motive in this way reverses the positions of the dif- ferent parts, and brings the boiler, smoke-stack, etc., behind, which is claimed to be an advantage, as when a locomotive runs with the smoke-box ahead, the smoke in the tubes moves in the same direction as che locomotive, consequently the draft created by the HA.ND-BOOK OF THE LOCOMOTIVE. 129 movement of the latter retards the draft in the tubes. It is also asserted that there is an advantage in having the water-tank in front, and the boiler and smoke-stack behind. The view of the track is thus entirely unobstructed, and there is no liability of its being obstructed by smoke or escape steam. The cabs of tank engines of this plan can be entirely closed up in cold weather, as it is not necessary to keep a communication to a separate tender open, as on ordinary engines. tablp: SHOWING THE NUMBER OF REVOLUTIONS PER MINUTE MADE BY DRIVERS OF LOCOMOTIVES OF DIFFERENT DIAMETERS AND AT DIFFERENT SPEEDS. Driving wheel Diameter. Speed in Miles per Hour. Revolu- tions per Mile. 20 25 30 35 40 50 4 ft. 0 in. 140 175 210 420 4 “ 3 132 165 198 395.5 4 « 6 “ 124 156 186 O) p. 373.6 4 « 9 « 118 148 177 207 si 354 5 0 140 168 196 .2 ^ s 336 5 “ 3 “ W o 134 160 187 IS 320.2 5 6 “ ■< 128 153 179 204 O) 305.9 5 9 Sg 146 170 195 292.3 6 “ 0 “ c 2 140 163 187 280.3 6 3 '' 135 157 179 224 269 6 '' 6 129 150 172 216 258.6 7 « Q U 120 140 160 200 240 I 130 HAND-BOOK OF THE LOCOMOTIVE. NARROW-GAUGE FAIRLIE LOCOMOTIVE. The above cut represents one of ‘‘Mason’s Narrow-Gauge’’ FairJie Locomotives. On this class of engines the tank is bolted to the boiler, and rests on two trucks with centre- pins, which enables it to pass around sharp curves with ease. The steam-pipes have ground joints, and turn in their socket when the engine is going around a curve. Number of Locomotives in the United States. — Whole number of locomotives in use in the United States at the close of 1873 was 14,200. Age of Locomotives. — Locomotives Nos. 1 and 2 built by Braithwaite & Co., London, England, 1838, or nine years after George Stephenson’s “ Kocket ” was placed on the track, are still running on the Reading Railroad, at Port Richmond, Philadelphia. Number of Miles Run by Locomotives. — En- gine No. 49 on the Reading Railroad, from August 1st, 1857, to November 1st, 1873, 447,138 miles. Number of Miles Run by Locomotives in One HAND-BOOK OF THE LOCOMOTIVE. 131 Year. — Engine 46 on the Pittsburg, Fort Wayne and Chicago Railroad, in 1872, 44,500 miles. Average number of miles run in one year by pas- senger and express locomotives was 26,000. Speed on Railroads. — The highest speed ever attained in this country, or perhaps in the world, and continued for any length of time, is that made by the Newspaper Express between New York and Phila- delphia, the run of 93 miles being made daily in If hours, including four stoppages. Speed on English Railroads. — The fastest speed ever attained, and continued for any length of time, by passenger and express locomotives on English railroads, was 50 miles per hour ; the average speed being about 35 miles per hour. Average speed of freight locomotives in England, about 15 miles per hour. Average speed of freight locomotives in the United States, about 12 miles per hour. Heavy Locomotives. — The largest locomotive in the world is the “Pennsylvania,’’ on the Reading Railroad. Diameter of cylinders, 20 inches ; stroke, 26 inches ; number of driving-wheels, 12 ; diameter of drivers, 4 feet ; weight of engine alone, 60 tons. The heaviest locomotives in Europe are the four- cylinder freight engines on the Northern Railway of France. Cylinders, 18 inches; stroke, 18 inches; 12 coupled wheels, 42 inches diameter ; weight of loco- motive, 66 tons. 132 HAND-BOOK OF THE LOCOMOTIVE. The dimensions of the steam-ports rank next in importance to the cut-off in their controlling influ- ence upon the proportions of the valve seat and face. They may justly be considered as a base, from which all the other dimensions are derived, in conformity with certain mechanical laws. Their value depends greatly upon the manner in which the ports are employed, whether simply for admitting the steam to the cylinder, or for purposes both of admission and escape. In case of admission, if the port is properly designed, it is evident that the pressure will be sustained at sub- stantially a constant quantity by the flow of steam from the boiler. But with the exhaust the case is dif- ferent, as the steam is forced into the atmosphere with a constantly diminishing pressure and less velocity. HAND-BOOK OF THE LOCOMOTIVE. 13S When a small travel of the valve is essential, the length of the port should be made as nearly jequal to the diameter of the cylinder as possible. • The following table will show the proper area of steam-ports and steam-pipes for different piston speeds, as it is assumed that for average lengths of pipe the area increases as the speed, and that a higher speed is usually attended by increased pressure : Speed of Piston. Port Area. Steam-pipe Area. 200 feet per minute. .04 area of piston. .025 area of piston. 250 u u (( .047 u (( .032 a a 300 u i( « .055 (C (( .039 a a 350 (i (i (( .062 u it .046 it it 400 (( u .07 u it .053 a it 450 u u (( .077 (C it .06 it a 500 u (i (( .085 (. it .067 it it 550 u (i u .092 u a .074 a a 600 u (( (i .1 (( it .08 it a BRIDGES. The width of the bridges is usually made of equal thickness with the cylinder, in order to secure a perfect casting ; but at times it becomes necessary to increase or decrease their width. The only danger from a narrow bridge is an over- travel of the valve, by which the exhaust passage would be placed in direct communication with the “ live steam ” in the chest, and followed by continual waste of the power. The width of bridges for different size cylinders of locomotives varies from | up to li inches. 12 134 HAND-BOOK OF THE LOCOMOTIVE. ECCENTRICS. The term eccentric is applied in general to all such curves as are composed of points situated at unequal distances from a central point or axis. Upon close inspection it appears that this is only a mechanical subterfuge for a small crank. This being so, a crank of the ordinary form may be, and frequently is, used instead of an eccentric — in point of fact, the latter is the real substitute, being a mechanical equivalent introduced, because the use of the crank is, for special reasons, incon- venient or impracticable. And since the shaft to which the eccentric is fixed here makes a half revolution while the piston is mak- ing one stroke, it follows that whatever device may be used for converting the reciprocating motion of the piston into rotatory motion, the slide-valve may be actuated by an eccentric fixed on any shaft which makes a half revolution at each stroke of the piston. HAND-BOOK OF THE LOCOMOTIVE. 185 It will now be observed that the eccentric and valve connection is nothing more nor less than that of a small crank with a long connecting rod ; the valve will therefore move in precisely the same man- ner as the piston, and will have in its progress from one extremity of the travel to the opposite like irreg- ularities, different only in degree. In other words, when the eccentric arrives at the positions for cut-off and lead, the valve will be drawn beyond its true position — measured towards the eccentric — by a distance dependent on the ratio between the throw of the eccentric and the length of its rod. When the eccentric stands at right angles to the crank, the exhaust closes and release commences at the extremities of the stroke; consequently, if the eccentric be moved ahead 30°, not only will the cut- off take place 30° earlier, or at a crank-angle of 120° instead of 150°, but the release, as well as the ex- haust, will take place 30° earlier, or at the 150® crank-angle. For a cut-off, say of 140°, there would be required an angular advance of 20°, and a lap equivalent to the distance these degrees remove the eccentric centre from the line at right angles to the crank ; for a cut- off of 160°, an advance of 10°, with a correspond- ing lap, and so on, the exhaust closure taking place respectively at the 160° and 170° crank-angles. This closure of the exhaust confines the steam in the cylinder until the port is again opened for the 186 HAND-BOOK OF THE LOCOMOTIVE. return stroke ; consequently the piston in its progress will meet with increasing resistance from the steam, which it thus compresses into a less and less volume. Such opposition, when nicely proportioned, aids in overcoming the momentum stored up in the recipro- cating parts of the engine, and tends to bring them to a uniform state of rest at the end of each stroke. Since the closure of one port is simultaneous with the opening of the other, a release will take the place of the steam which was previously impelling the piston. Within certain limits an early release is produc- tive of a perfect action of the parts, for an early release enables a greater portion of the steam to escape before the return stroke commences ; whereas, a release at the end of the stroke would be attended by a resistance of the piston’s progress, from the simple fact that steam cannot escape instantaneously through a small passage, but requires a certain defi- nite portion of time, dependent on the area of the opening and the pressure. The advance of the eccentric denotes the angle which the eccentric forms with its position at half- stroke, when the piston is at the commencement of its stroke, and is called Angular Advance, ECCENTRIC RODS. The variable character of the lead opening, in a shifting-link motion, depends upon the manner in HAND-BOOK OF THE LOCOMOTIVE. 137 which its eccentric rods are attached, and its amount depends on the length of those rods. The shorter the eccentric rods the greater is the front admission, and the less is the admission for the back. The quality of the motion derived from the link is modified by the position of the working cen- tres, and most especially of the centre of suspension and connection. The centre of suspension is the most influential of all in regulating the admission; and its transition horizontally is much more efiicacious than a vertical change of place, to the same extent. Length of the Eccentric Rods. — The length of the eccentric rod is the distance from *the centre of the driving-axle to the centre of the rocker-pin, when the rocker stands plumb. Formula by which to find the Positions of the Eccentric on the Shaft. First Draw upon a board two straight lines at right angles to one another, and from their point of intersection as a centre describe two circles, one rep- resenting the circle of the eccentric, the other the crank shaft ; draw a straight line parallel to one of the diameters, and distant from it the amount of lap and lead ; the points in which this parallel intersects the circle of the eccentric are the positions of the 'Orward and backing eccentrics. Second. Through these points draw straight lines 12 * 138 HAND-BOOK OF THE LOCOMOTIVE. from the centre of the circle, and mark the intersection of these lines with the circle of the crank-shaft ; measure with a pair of compasses the chord of the arc intercepted between either of these points and the diameter which is at right angles with the crank, the diameters being first marked on the shaft itself; then by transferring with the com- passes the distance found in the diagram, and marking the point, the eccentric may at any time be adjusted without difficulty. Example. — Let F G and E C be the two straight lines at right angles to each other ; the circle described with A B as a radius be the end view of the shaft ; the circle described with A C as a radius be the circle described by the centre of the eccentrics ; and H I the line parallel to E C, and distant from it the amount of the lap and lead. Then if F G represents the direction of the crank when on the centre, H and I will be the positions of the centres of the eccentrics, according to the rule. If, then, the points K and L, in which the lines A H and A I intersect the circle representing the shaft, be transferred to the shaft, by laying off on its end the two diameters, and the chords B K and L M, the eccentrics can readily be set. HAND-BOOK OF THE LOCOMOTIVE. 139 The above cut represents the position of the valve at full stroke, or when the crank is at the dead centre. S, steam ports ; D, exhaust opening in valve seat ; E, exhaust cavity in valve ; A, lead, THE SLIDE-VALVE. The slide-valve is that part of a steam-engine which causes the motion of the piston to be reciprocating. It is made to slide upon a smooth surface, called the valve seat, in which there are three openings — two for the admission of steam to the cylinder alternately, while the use of the third is to convey away the waste steam. The first two are, therefore, termed the steam-ports, and the remaining the eduction or ex- haust port. In examining the special application of the slide- valve to the steam-engine, it will be necessary to con- sider what the requirements of the engine are ; for the valves, of whatever kind, being to that machine what the lungs are to the body, must necessarily be so actu- ated as to regulate the admission and escape of the 140 HAND-BOOK OF THE LOCOMOTIVE. steam, which is its breath, in accordance with the conditions imposed by the motion of the piston. The valve may be said to be the vital principle of the engine. It controls the outlet to the coal and wood pile. It is, therefore, of the highest importance that it should work practically under all circum- stances. Now the admission of steam is one thing and its escape is another, and though both may be regulated by what is called one valve, because it is made in one piece, yet this is not by any means necessary. Four separate valves may be, and sometimes are, employed in stationary engines — a steam and an exhaust valve at each end of the cylinder ; but the functions of all these are distinctly performed by the common three- ported slide-valve. Position of the valve at half stroke. It is evident that the admission cannot continue longer, in any case, than the stroke does, so that by HAND-BOOK OF THE LOCOMOTIVE. 141 the time that is completed, the valve must have opened and closed the port. These conditions determine the modification of the movement which must be used, and the greatest breadth of the port for any assumed travel of valve. When the motion of a slide-valve is produced by means of an eccentric, keyed to the crank-shaft and revolving with it, the relative positions of the piston and slide-valve depend upon the relative positions of the crank and eccentric. The greatest opening of the port is half the travel of the valve ; in this case the steam is admitted during the whole stroke of the piston, at the beginning of which the valve, which has no lap, is at the centre of its travel. The annexed cut shows the position of the valve when the link is in mid-gear, or when the link-block is .directly under the saddle, and the reverse latch in the out notch, L repre- sents the lap. If the eccentric be so placed that at the beginning of the stroke of the piston the valve is not at the 142 HAND-BOOK OF THE LOCOMOTIVE. centre of its travel, the opening of the port will be reduced, and it will be closed before the piston com- pletes its stroke. In this case, the opening of the port will be less than half the travel, by as much as the valve, at the beginning of the stroke of the piston, varies from its original central position. And when the valve is at half stroke it will overlap the port on the opening edge to the same extent. The point in the stroke of the piston at which the port will be closed and the steam cut off, will depend upon the angular position of the eccentric at the be- ginning of the stroke. When the valve is so formed that, at half stroke, the faces of the valve do not close the steam-ports inter- nally, the amount by which each face comes short of the inner edge of the port is known as inside clearance. From the nature of the valve motion, it follows that the distribution is controlled by the “ outer and inner edges of the extreme ports and of the valve.” The mere width of the exhaust-port or thickness of bars is immaterial to the timing of the distribution. The extreme edges of the steam-ports and those of the valve regulate the admission and suppression; and the inner edges of the ports and the valve com- mand the release and compression. For every stroke of the piston, four distinct events occur — the admission, the suppression, the release, and the compression. HAND-BOOK OF THE LOCOMOTIVE. 113 The advance of the valve denotes the amount by which the valve has travelled beyond its middle posi- tion, when the piston is at the end of the stroke, and is known as linear advance. The slide-valve is said to be very imperfect and wasteful of fuel ; but, on account of its simplicity, durability, and positive action, it has been able to compete with the best modern improvements, and it is at the present time the only valve in use on all the railroads in the world. With all its defects it must be conceded that noth- ing has yet been introduced that has so well answered the purpose of controlling the induction and eduction of steam to the locomotive cylinder as the ordinary slide valve, nor does it at present seem probable that it ever will be superseded. FRICTION ON THE SLIDE-VALVE. The great aim of all engineers has been to removt; the weight caused by the pressure of the steam from the back of the slide-valve ; but it has been considered almost impossible to produce a frictionless slide-valve. The percentage of the friction of the slide-valve, as compared with the cylinder’s power, ranges between 10 and 20 per cent., according to the condition of the valve, variation in the position of the gear, etc. ; for while the cylinder decreases in power as the crank approaches the end of the stroke, the friction of the valve and eccentrics increases. 144 HAKD-BOOK OF THE LOCOMOTIVE. Length of the Valve Rods. — The length of the valve rods is the distance from the centre of the rocker pins to the centre of the valves, when the valves are placed centrally over the ports and the rocker arm stands plumb. LAP AND LEAD OP VALVE. Lap, OP lap of valve, is understood to be the dis- tance the valve overlaps each steam opening when placed centrally over the port. The amount of lap is regulated by the point at which the steam is to be cut off, or the degree of expansion to be attained, as without lap there would be no expansion,, because the suppression and release would occur at the same time. Lap on the steam side is termed outside lap. Lap on the exhaust side is known as inside lap. Lead of Valve. — Leac? is understood to be the width of port opening given by any valve on the steam end when the crank is at either dead centres, and the angular distance of the crank from its zero at the instant this opening commences, is termed lead angle. Lead on the steam side is denominated outside lead^ or lead for the admission ; on the exhaust side it is inside lead, or lead for the exhaust. Lap and Lead of Valve. — Lap and lead procure an early and efficient release, because the lead of the exhaust, or the amount by which the valve is open to the exhaust, at the end of the stroke, is increased by • as much as the addition of lap on the outside. HAND-BOOK OF THE LOCOMOTIVE. 14 /$ Lap, Lead, and Travel of Valve. — As lap, lead, and travel regulate the distribution of steam, an alter- ation of any one of these affects it in a definable man- ner. If they be equally varied in conjunction, the distribution remains the same. BALANCED SLIDE-VALVE. The mechanical difficulty of producing a practi- cal balanced slide-valve, trustworthy under every kind of locomotive work, seems to have been success- fully overcome. Balanced valves are now in use on nearly all the principal railroads in the coun- try, and are said to meet all the demands of locomo- tive practice. It is claimed that the saving in the wear and tear of valve motion with balanced valves, especially in the case of large engines, is very great, as they can be kept out of the repair shop much longer than en- gines with common slide-valves. It is also asserted by railway mechanics that they are not liable to any sudden derangement, either on fast passenger trains or on freight trains; and the comfort of the drivers is greatly enhanced by having an engine that can be notched up or reversed as easily with the throttle open as shut. Miles ran with balanced valves without facing, 75,000 to 150,000; miles run with common slide- valves without facing, 30,000 to 50,000. 13 K 146 HAND-BOOK OF THE LOCOMOTIVE. TABLE SHOWING THE AMOUNT OF LAP AND LEAD ON THB VALVES OF LOCOMOTIVES IN PKACTICE, ON 35 OF THE PRINCIPAL RAILROADS IN THIS COUNTRY. Locoraotives Running Express Passenger Trains, 25 use \ inch outside lap. I inch inside lap. 5 inch travel of valve, yij inch lead in full gear. { I inch outside lap. tV inch inside lap. 4| inch travel of valve. J inch lead in full gear. I inch outside lap. i inch inside lap. 5 inch travel of valve. I inch lead in full gear. Locomotives Running Express Accommodation Trains, f inch outside lap. I inch inside lap. 5 inch travel of valve, inch lead in full gear. 1 inch outside lap. inch inside lap. 5i inch travel of valve, y’g inch lead in full gear. f inch outside lap. y^^ inch inside lap. 4i inch travel of valve. I inch lead in full gear. 20 use ^ 10 use 6 use HAND-BOOK OF THE LOCOMOTIVE. 147 Locomotives Running Heavy Freight Trains, 19 use 11 use ^ I inch outside lap. yig inch inside lap. \ 5 inch travel of valve, yig inch lead in full gear. f I inch outside lap. I I inch inside lap. ] 4:1 inch travel of valve, i inch lead in full gear. 5 use ^ I inch outside lap. inch inside lap. I 4| inch travel of valve, j’jy inch lead in full gear. THE LINK. this general term have many strong points of resem- blance, and subserve a common object. By means of the link the engineer is able at will to change the direction of the engine, with only the loss of time required for overcoming the momentum of the moving parts and developing the like in a reverse direction. 148 HAKD-BOOK OF THE LOCOMOTIVE. More than this was not contemplated in the orig= inal discovery of the link. Subsequently, however, it was found to be capable of regulating the cut-off of the steam, so that the power could always be ad- justed to the work required. The extreme simplicity of the parts of the link- motion has enabled it to compete successfully with all rivals, and at the present day it remains substantially in its original form. The motion of each eccentric prevails in that half of the link to which it is coupled, and at the centre the motion of the link is equally composed of the two eccentrics. A link operated by two fixed eccentrics forms, when properly suspended, an exact mechanical equiv- alent of the movable eccentric. Unlike the latter, however, its motion is capable of an accurate adjust- ment, which practically obviates the effect of irregu- larities in cut-off and exhaust closure, attributable to the angularity of the main connecting rod. Horizontal motion, communicated to the link by the joint action*^of the eccentrics, is a minimum at the centre of its length, where it is equal to twice the linear advance, and it increases toward the extremi- ties of the various periods of the block in the link, or of the link on the block, on the general principle that admission varies with the travel of the valve. The distribution derived from the link is affected by the length of the connecting-rod relative to that of HAND-BOOK OF THE LOCOMOTIVE. 149 the crank — the shorter the rod, th^ greater is the front admission, and the less is the admission for the back stroke ; therefore the term ‘‘ link-motion,'’ in so far as it involves the relation of the valve’s mo- tion to that of the piston, virtually includes the pro- portions of the piston motion. - The nature of the motion derived from the link is modified by the positions of the working centres, and most especially of the centres of suspension and con- nection ; the centre of suspension is the most influen- tial of all in regulating the admission, and its tran- sition horizontally is much more efficacious than a vertical change of place to the same extent. The periods of admission in half-gear are much more sensitive to variation by mode of suspension and connection than those in full and mid-gear. It is of great consequence to set the motion right for this position as regards the quality of the admis- sion, because these diflTerences for other positions are then inconsiderable. As the vertical movement of the body of the link with the consequent slip between the link and the block is the least possible when the suspended centre lies in the centre line of the link, increasing as the centre is removed laterally, the centre line of the link is, in this respect, the most favorable locality for the suspension, though not always practicable for equal admissions. In practice it has been found that the stationary 13 * ^ 150 HAND-BOOK OF THE LOCOMOTIVE, M 'Sh S ci r c3 go^ bC-ZH t > o .^O a g rC: ‘r^ ^ a G ^.2 sg .S [if ^ ' '^ C O) c3 S ■ Of'o ^ (D ^ o ^ s c - 2 - rS « 2o ^ ^ g ^ S n"l ^ ai « S||| g 55 *s. ^ C ^ r-H 03 ^^5 g-3 o ^ ^ _K a» rG G G “ n si « .'5.2 y .g opv 2^ s ” - -..-■E^ o 2 ^ ^ S ^ G ^ g 2r2 ^ ^ 2'^ i-G rG , rG ’-!2 G •'13 o CQ ^ rT-( G ^ ^■'■'l 2 _^'^ ^ .g -i''.~-...S " S.S.C^G a G-f^ 33 G rrt ^ m g ’TT! I G CO ^ r <1 - 2 .S G <1^ ‘^•GJ G cThTH .2 ns 'G'G t- HAND-BOOK OF THE LOCOMOTIVE. 151 and shifting links have not the same neutral centres of suspension ; that, in general, the stationary link should be hung by a centre in the neighborhood of the middle of its length, and the shifting link towards one of the extremities. The periods of expansion and release increase as those of admission are diminished, and when the points of suppression are equally adjusted those of release do not considerably differ. The utmost period of expansion obtained by a sta- tionary link in mid-gear is 38 per cent, for 12 per cent, of admission, in which case the steam is cut off at less than one-eighth of the stroke, and expanded into a volume of 50 per cent., or one-half stroke, — 4 times the initial volume, exclusive of clearance, — after which it exhausts during the remaining half-stroke. With the stationary link the shortest admission is 11 per cent., or one-ninth of the stroke, expanding into 50 per cent.,^or times the initial volume, before the release takes place. With the shifting link, the smallest attainable admission is about 17 per cent., or one-sixth of the stroke ; this is about one-half more than what is ob- tained by the stationary link, the difference being due to the excess of lead yielded by the shifting. As the release takes place at half-stroke, the shift- ing link cannot expand the steam above three times its initial volume, exclusive of clearance. The average period of admission in full gear does not exceed 75 per cent., or three-fourths of the stroke. 152 HAND-BOOK OF THE LOCOMOTIVE. More than this should not be required, nor indeed could it be beneficially employed at regular speed ; the admission may, however, be increased by forcing the mechanism of the valve beyond full gear — that is, by causing the block to work in the extreme overhung parts of the link, which must be extended for the purpose beyond the centres of connection ; by this expedient the throw of the valve is increased. ADJUSTMENT OF THE LINK. Besides the qualities possessed in common by the two motions, the link has that of adjustability, a very important feature, and one which especially charac- terizes it. As the tendency of the connecting-rod angularity in a direct acting engine is to produce a later cut-off on the forward stroke than the amount required, and since with the link the cut-ofi* in either stroke de- pends on its degree of elevation or depression, it fol- lows that if we suspend the link in such a manner as to cause a suitable elevation for the forward stroke, the result will be a perfectly equalized motion for the gear in question. Aud again, if the equalization be made applicable to all gears, then the link may be suspended at any point between the full forward and full back without an appreciable inequality appearing between the cut- os's or the exhaust closures of either stroke. But a practical difficulty here arises — the link- HAND-BOOK OF THE LOCOMOTIVE. 153 block moves upon a fixed arc, while the link rises and falls ; consequently, for each revolution of the crank the link will slip back and forth a certain dis- tance on its block. Should this slip be excessive in any particular gear, and the engine run a long time in this gear, the faces of the link would become worn, “ lost motion ” would ensue, and the accurate action of the parts would be destroyed. It is also obvious that the slip must grow smaller as the link-block draws nearer the point of suspen- sion, because this fact indicates that the stud of the saddle should be placed — when a minimum value of the slip is required at a certain point of suspen- sion — as nearly over such point as possible. The stationary link gives a constant lead. With the shifting link the lead varies with the expansion. The linear advance of the eccentrics, with the sta- tionary link, is always less than that of the valve, and is efiected by the length of the eccentric rods. With the shifting link, the linear advance of the valve is in all cases equal to that of the eccentrics in full gear, independently of the length of the rods ; by full gear is meant that the fore-rod is brought into the centre line of the valve-rod. In other positions the linear advance of the valve varies precisely with the lead. The link was invented by Williams, of New Castle, England. 154 HAND-BOOK OF THE LOCOMOTIVE. The above cut represents an end view of the spring piston packing, such as is used in locomotives, i represents the front end of piston-rod ; T, piston-head ; A, wings ; /, studs ; e, jam- nuts ; dj springs ; holes for follower-bolts ; C, C, rings. STEAM AND SPRING CYLINDER PACKING FOR LOCOMOTIVES. The chief merit of steam packing is said to con- sist in its absence of friction, when not under pres- sure of steam, in descending grades and upon ap- proaching stations. It is also claimed for steam packing that it can be more cheaply constructed than spring packing, and, after being first put in the cylinder, requires no sub- sequent adjustment by the engineer. On the other hand, it is urged for spring packing HAND-BOOK OF THE LOCOMOTIVE. 155 that it is more steam-tight than steam packing, less liable to blow, and is not affected by varying steam pressures in the cylinder. And while not absolutely without friction under the above circumstances, is nearly so when fitted with springs of proper elasticity, say sufficient to keep the rings in contact with the cylinder without exerting undue pressure. The highest number of miles run with a set of steam packing without repair, 200,000; average, 150.000. The highest number of miles run with a set of spring packing without repair, 150,000; average, 100.000. Setting out Spring Cylinder Packing. — Setting out spring packing in the cylinders of locomotives requires the exercise of great care and judgment, for, like valve setting, no general rule can be laid down — the proper adjustment must in all cases de^ pend on the skill and intelligence of the engineer. An ignorant or careless adjustment of the packing may at any time not only materially lessen the power of the engine, but literally ruin both the packing and the cylinders. If the packing be set out too tight, the friction between the packing-rings is in- creased to such an extent that the power that ought to be transmitted from the pistons to the driving- wheels is wasted in overcoming the friction in the cylinders. If, on the other hand, the packing is 156 HAND-BOOK OF THE LOCOMOTIVE. allowed to be slack, the steam will escape and oc- cupy the cylinder in front of the piston on the ex- haust end, causing excessive cushioning, with great waste of steam and loss of power in the engine. PACKING FOR THE PISTONS AND VALVE RODS OF LOCOMOTIVES. There is probably no part of the locomotive more frequently out of order, or gives greater annoyance, than the piston- and valve-rod packing. A vast deal of study and ingenuity have been applied to the removal of this annoyance, and the production of a durable piston-rod packing. Wire gauze, gum, soapstone, jute, asbestos, metallic pack- ing, and a great variety of other materials have been tried, but without very satisfactory results. Hemp, when properly used, serves a good purpose, as it has the advantage of always being ready and requiring no special tools to prepare it for use, nor any particular size of stufSng-box, and can be used as well by the unskilful as the skilled man ; but its HAND-BOOK OF THE LOCOMOTIVE. 157 usefulness is limited, particularly where steam of a high pressure is used, as it soon loses its elasticity, and, in consequence, becomes worthless. Soapstone gives tolerably good results, and has the advantage of producing less friction, and is not so liable to flute or cut the rods as hemp. But it is not to be expected that the same kind of packing would give the same results on different roads, as it is well known that the packing wears out faster on sandy roads than those that are not sandy ; nor does packing give the same service on slow freight loco- motives that it does on fast passenger engines. The failure of packing to give satisfactory results in many cases is due to a want of skill and judgment on the part of the persons using it. The softer the packing can be kept in the stuffing- boxes, the more service it will do ; for when it loses its spring or elasticity, it materially interferes with the easy working of the engine, and any extra tighten- ing has a tendency to char and render it worthless. If the packing leaks badly around the rod after being renewed, and it is found impossible to make it steam-tight, it is always better, if time will permit, to take out one or two rings and reverse them, which will be found, in most cases, to give relief ; or if it becomes necessary to tighten the packing, it is always better to do so when it is cold, or after the engine has been standing still for some time. Metallic packing, for piston-rods, has been tried 158 HAND-BOOK OF THE LOCOMOTIVE. by a number of the principal railroads in the coun- try ; but its use has been generally abandoned on account of its results not bearing out its first costs and needed repairs. There is at present, and always has been, a great need of a permanent and reliable piston-rod pack- ing. Such an article would not only be*productive of very economical results on railroads, but would greatly lessen the labors of engineers. Rule for finding the size of Piston- and Valve-Rod Packing. Measure the piston- or valve-rod; then measure the stem of the stuffing-box; divide the difference between them by two. For example: Rod 2 inches, box 4 — packing 1 inch ; rod 1 inch, box 2 — packing J inch ; rod | inch, box li — packing | ; rod 2 inches, box — packing f ; rod H inches, box 4 inches — packing IJ. CUGNOT’S LOCOMOTIVE— 1769. HAND-BOOK OF THE LOCOMOTIVE. 159 BRASSES FOR DRIVING AXLES OF LOCOMO- TIVES. The importance of good workmanship in fitting the brasses in the boxes of driving axles is well known to railway mechanics, because unless thor- oughly fitted they are liable to become loose and give trouble. Hexagon-shaped brasses generally give better results than either half-round or gib brasses, when properly fitted. The most permanent device for securing half round brasses in driving boxes is by means of brass pins driven in holes drilled through the boxes and brasses. Octagon brasses are best secured by means of lugs cast on the brass, in the ceiitre of their length, and fitted into recesses cast in the box. This is considered better than a flange on the ends, as the thickness of the brass can be seen without taking it out. 160 HAND-BOOK OF THE LOCOMOTIVE. Best Milage for Driving Brasses before Becoming Loose, Half-round Brasses, Highest. . 120,000 Lowest. 10,000 Octagon “ ... . 125,000 25,000 Brass gibs, fitted with Babbit metal. . 100,000 85,000 Babbit metal possesses an advantage in case the box should get hot, — the metal will run and prevent cutting. LATERAL MOTION. Lateral motion is understood to be the distance or the clearance between the rails and flanges of loco- motive and truck wheels, and which in general prac- tice is about i of an inch for the forward driving- and . truck-wheels, and about f for the rear drivers. The difference in gauge for front and rear drivers is to allow for the radius of the curve, and is of great importance, especially in the case of ten-wheeled en- gines, or those having an extended wheel-base. A liberal allowance of lateral motion is beneficial, as it lessens the friction, more especially in curving, and saves a large amount of power in drawing trains ; but wide lateral motion involves a certain amount of danger, as there is a liability of breaking the flanges when thrusted against the rail, or forcing the wheels ofi* the axles when striking guard-rails and frogs. Wide lateral motion is also attended with too much oscillation of the car body for safety, when running around sharp curves at a high speed. HAITD-BOOK OF THE LOCOMOTIVE. 161 The variation in the wheel-gauge of locomotives is immensely less than that of cars. This is necessarily so from the fact that the one is employed upon a fixed gauge, and runs repeatedly over the same track; while the others, from the general and ex- tended character of our railway traffic, must pass over other lines. SPEED INDICATORS. There is probably nothing connected with the run- ning of locomotives so uncertain as the time made by trains between the different points on their trips, or for any number of consecutive hours ; for while it is known that express and light passenger trains often exceed 30 miles an hour on one part of their trip, they as often fall below 25 miles an hour on the other part, without any apparent cause, even where the road is perfectly level. Many of the acci- dents that occur on railroads might be attributed to this irregularity of speed, more particularly so in the case of light freight trains. To obviate this difficulty, speed indicators should be placed on every locomotive, which would enable railroad officers to ascertain the regular speed cf trains at different points on the trip, also show the ability of engines of a certain class and size to make a uniform specified time all over the road. 14* ' L 162 HAND-BOOK OF THE LOCOMOTIVE. o HA^iTD-BOOK OF THE LOCOMOTIVE. 163 LOCOMOTIVE BOILERS. The boiler is the most important part of a locomo- tive engine, and the |useful effects of the machine depend, in a great degree, on its strength and effi- ciency. In fact it might be said that the boiler is the backbone of the whole machine, as it has to withstand the effect of every shock and strain to which the moving mass is exposed, and yet there is no part of locomotive construction in which there has been so little improvement as in the boiler. Special machinery has been made for manufacturing nearly every other part, while in the construction of the boiler the same appliances are still employed as was used years ago. In all other parts of the machinery where great strength is required, gauges and templets are used to insure the most exact fitting, while in boiler con- struction very little apparent effort has been made to secure accurate workmanship. It is difficult to see why some analogous system is not employed by boiler- makers as well as by machinists. The sheets of the locomotive boilers are exposed to the operation of various powerful chemical and me- chanical forces, all of which have a tendency to hasten their destruction. The first and chief of these forces is the pressure of steam, which generally, on locomotive boilers, is of tremendous elastic force. i64 HAND-BOOK OF THE LOCOMOTIVE. Then there are the strains caused by the jarring of the locomotive, especially on some roads, and at some seasons of the year, when the earth is loosened by the breaking up of the frost, and the sleepers and rails are in a shaky condition. Next the oxidation caused by the ingredients in the water, the mechanical force of the water itself, and its impact against the walls of the boiler, the injurious effects of which must be severe. All these strains combined affect the several parts of the boiler — the intense heat rendering the material more crystalline and more liable to frac- ture ; the continual jar having a tendency to loosen the rivets and weaken the whole structure. A boiler may be abundantly strong, but insuffi- ciently stiff ; whereas, in a locomotive boiler, above all others, identity of form is of great importance, as, besides the ordinary contingencies of overstrained joints and leakage, resulting from change of form, there are, unavoidably, connections and attachments to be made here and there which can only be main- tained in good order under superior conditions of stability of parts. A locomotive boiler must evidently possess other features of strength than those required in a mere steam generator. However strongly and independ- ently the frames of the engines may be constructed, the simple holding of the boiler in place upon them necessitates considerable extra stiffness in the latter. HAXD-BOOK OF THE LOCOMOTIVE. 165 The boiler answers, in part, as a framing, and not only stiffens the structure, preventing side or lateral flexure, but sustains the entire fore and aft strain of the engine, as developed in cylinders, since the centre line of the boiler is so far above that of the cylinder, giving the latter so much leverage that the strain tends to pry the boiler asunder at the junction of the waist with the fire-box. Kegarding the locomotive-boiler as a cylinder with flat ends, greatest strain falls necessarily upon the longitudinal seams, and the least upon the cur- vilinear seams at and between the ends of the boiler. The longitudinal seams, therefore, should in all cases be double-riveted, while for curvilinear seams, bearing only half the strain that is upon the other, the single-riveted seam is sufficient, being propor- tionably stronger, with respect to strains arising from steam pressure, than the other. Steel plates are now very generally used, and their importance as a material for the construction of loco- motive boilers is fully established, as is shown by the successful results of careful experimental investiga- tions. Steel is always crystalline in its nature. Whatever the jarring and straining to which it is exposed, its quality cannot be altered in that respect ; while its toughness, notwithstanding its crystalline structure, is to wrought-iron as two to four, and in some cases more than that. The thickness of iron plates generally used for 166 HAND-BOOK OF THE LOCOMOTIVE. locomotive boilers ranges from i to | ; but wlien steel is used, this thickness can be reduced or even iy as steel plates i inch thick, for boilers 48 inches in diameter, are perfectly safe at 150 pounds’ pressure per square inch, besides affording increased facilities for the transmission of heat from the fire to the water. It is evident then that in case no more steam pressure is carried, the repair expenses of steel boilers, as compared with iron of equal section, will be decreased, not only in proportion to their superior strength, but in a great proportion by reason of their elasticity, hardness, granular construction, and resistance to corrosion. And if proportionately higher steam pressure is carried, so that the relation of strength to strain is the same as in iron boilers, the repair expenses will still be decreased by reason of the last-named quali- ties of steel. What is true as to the expenses of maintenance is true as to safety. Kecent discussions, and recently compiled facts on the subject of boiler explosions, show quite conclusively that the larger proportion of these casualties result simply from the want of proper strength in the boiler. Kecent experiments on standard kinds of iron plates showed a mean strength of 49,215 pounds to the square inch, while experiments made at the same time on steel plates showed a mean strength of 85,275 pounds. The difference in the weight of iron and HAND-BOOK OF THE LOCOMOTIVE. 167 steel plates of the same dimensions is not great enough to be of practical importance. Other things being equal, therefore, a steel boiler is 73 per cent, stronger than an iron boiler. PROPORTIONS OP THE LOCOMOTIVE BOILER, PROM THE BEST MODERN PRACTICE. Boiler sheets, best cold-blast charcoal iron, | inch thick, or best homogeneous cast-steel, inch thick, or horizontal seams and junction of waist in fire-box double-riveted. Waist, formed of two sheets rolled in the direc- tion of the fibre of the iron or steel, one longitudinal seam in each, located above the water-line. All longitudinal seams double riveted; curvi- linear seams single riveted. All iron sheets i inch thick riveted with f inch rivets, placed 2 inches from centre to centre. Steel plates inch thick, riveted with f inch rivets, placed inches from centre to centre. Extra welt pieces, riveted to side of side sheets, providing double thicknesses of metal for stud-bolts and expansion braces. WAGON-TOP AND STRAIGHT BOILERS. The wagon-top possesses some very important ad vantages over the straight boiler, especially where impure water is used, as it affords greater steam 168 HAND-BOOK OF THE LOCOMOTIVE. WAGON-TOP LOCOMOTIVE BOILER. HAND-BOOK OF THE LOCOMOTIVE. 169 room, larger water surface over the furnace, and de- creases the liability to foam. It is easier of access when it becomes necessary to remove the mud and scale from the crown -sheet, or when repairs are necessary to the' numerous braces over the furnace ; it also distributes the weight to a greater advantage on the drivers than does the straight boiler. The cylindrical part can be smaller in diameter, and consequently lighter than the straight boiler, thereby lessening the weight upon the truck, while the furnace end will have greater weight and will give proportionately more adhesion to the driving- wheels. The straight boiler can be built at less cost than the wagon- top, and is subjected to the fewer unequal strains, but the advantages of the wagon-top over the straight boiler more than compensate for the above defects. Wagon -top boilers carry their water better than the straight boilers, because they have a larger body of hot water in which to neutralize the supply of cold water from the pumps. They use dryer • steam, for the reason that the dome from which it is taken is higher than in the straight boiler, hence the steam is less likely to become saturated by the surging of the water in the boiler, produced by the galloping movement of the engine. The heating surface and water space of the wagon- 15 170 HAND-BOOK OF THE LOCOMOTIVE. top is greater than that of the straight boiler, with about the same amount of steam room ; and, in as- cending high grades, the wagon-top possesses great advantages over the straight boiler on account of the great body of hot water carried. It is generally un- necessary to pump where the engine is performing her hardest labor. Two domes are preferable to one on boilers with limited steam space, and on boilers using impure water, provided steam is taken from the two domes, as there is less variation in the water level, and dryer steam is obtained in the cylinders. The crown or upper sheet of the wagon-top is nec- essarily weaker than that of the straight boiler on ac- count of its large radius. This is often still further weakened by cutting a hole for the dome in it, half as large as the diameter of the cylinder of the boiler. A single-riveted dome, as ordinarily made, does not restore much above half the strength thus taken away. THE EVAPORATIVE POWER OP LOCOMOTIVE BOILERS. The quantity of water evaporated by a boiler in a given time depends not only on the heating surface, grate surface, and draft area, but also upon the con- ducting powers of the boiler and the quantity of air which passes through the furnace in a given time. HAND-BOOK OF THE LOCOMOTIVE. 171 A locomotive boiler, for instance, burning 10 pounds of coal on each square foot of grate-surface in an hour, will evaporate about 9 pounds of water for each pound of coal under the most favorable conditions. The same boiler running at high speed, and burning 75 pounds of coal on each square foot of grate-surface, will evaporate 7 pounds of water for .each pound of coal burned. The total quantity evaporated in an hour in the first case will be 10 X 9 = 90 pounds of water for each square foot of grate-surface ; and in the second case, the same boiler, under a forced draft, will evaporate 75 X 7=525 pounds of water in one hour. Here there is a vast difference in the total amount of evaporation ; but each pound of coal, under the forced draft, pro- duces less steam, in the proportion of 7 to 9 pounds, so that while the economy of fuel in one sense is less, the total amount of work done by the sama boiler in the same time is very much greater with the higher rate of combustion. There are probably no phenomena connected with the generation and utilization of steam so imper- fectly defined, either theoretically or practically, at present, as those connected with the quantity of air which passes through the furnaces of boilers under varying conditions of draft. It has been generally assumed from the experi- ments of scientists that in ordinary practice double the amount of air necessary for complete combustion 172 HAND-BOOK OF THE LOCOMOTIVE. passes through the furnace. Hence all attempts to reduce the laws of evaporation of boilers to fixed and definite rules of practice for all conditions of draft, have thus far been based on assumptions which have no definite and precise foundation in practice. Experiments are greatly needed to determine the rate of combustion for varying conditions of draft, as well as the quantity of air actually drawn through the furnaces under these varying rates of combustion. Such determinations are necessary in order to estab- lish the corresponding temperatures of the furnaces and the gaseous products of combustion, and from these the transfer of heat by radiation and contact in the furnaces and flues respectively. HEATING SURFACE, STEAM ROOM, AND WATER SPACE IN LOCOMOTIVE BOILERS. The importance of extent in the surface of water, in a boiler, consists in the facility afforded for the ready egress of the steam, as evolved by the heating surface. The most satisfactory results are obtained when the water space is equal to the heating surface, and any deviations from these proportions are always attended with some disadvantage, though doubtless unappreciable until the disproportion arising from the increase of heating surface becomes very great. The engine whose steaming capacity is worked nearly or quite to its maximum while hauling trains HAITP-BOOK OF THE LOCOMOTIVE. 178 upon a level, will require an extra strain to furnish the steam over the grade, from which few roads can claim an absolute immunity. The advantage of sur- plus steam space can hardly he over-estimated, espe- cially in handling heavy trains. In the case of locomotives it is almost impossible to fix any ratio whatever between the water space and heating surface, since the former, of necessity, is limited, and every additional row of tubes, to increase the heating surface, reduces the area of the water space. So with the steam room, to secure dryness of steam and steadiness of action, large space is desirable ; but it is limited by the same considerations that restrict the water space — though the evils arising from limited steam room are relieved, to a certain extent, by the use of domes and the dry pipe. The only practical rule for the construction of loco- motive boilers, with respect to water space and steam room, seems to be, for a given heating surface, to se- cure as large a water and steam space as possible — the larger the better — within the limits imposed by restriction in the size of the boiler. Very excellent performances have been obtained from boilers with an area of water surface -^3 that of the heating surface, and a steam room about one cubic foot to one square foot of water surface. 15 * 174 HAND-BOOK OF THE LOCOMOTIVE. HEATING SURFACE TO GRATE SURFACE - IN STEAM BOILERS. Diameter of cylinder, , Stroke, Heating surface in fire-box, . ‘‘ “ tubes, . Total heating surface, , Area of grate, .... 40.1 sq. feet of heating surface to 1 . 16 inches. . 24 ‘‘ . 100 square feet. . 862 ‘‘ ‘‘ . 962 '' . 24 ‘‘ ‘‘ foot of grate surface. Diameter of cylinder, . . . .15 inches. Stroke, 22 “ Heating surface in fire-box, . . .85 square feet. ‘‘ “ tubes, . . .645 “ Total heating surface, . . . . 730 Area of grate, 11 “ ‘‘ 66.4 sq. feet of heating surface to 1 sq. foot of grate surface. Diameter of cylinder, . Stroke, .... Heating surface in fire-box, ‘‘ tubes. Total heating surface, . Area of grate, 62 sq. feet of heating surface , . 18 inches. . 22 ‘‘ . . 116 square feet. . 813 ‘‘ . 929 . 15 1 sq. foot of grate surface. Rule for finding the Heating Surface in Locomotive Boilers. Multiply the length of the sides and ends of the fire-box by the height in inches ; multiply the length HAND-BOOK OF THE LOCOMOTIVE. 175 of the crown-sheet by its width in inches. Add these products together, and subtract the combined area of all the tubes and fire-door ; divide the remainder by 144, and the quotient will be the heating surface in the fire-box in square feet. Rule for finding the Heating Surface in the Tubes of Locomotive Boilers, Multiply the circumference of one tube in inches by its length in inches ; multiply that product by the whole number of tubes, and divide this product by 144, which will give the heating surface in the tubes in square feet. (See Table of Superficial Areas of Tubes.) Rule for finding the Heating Surface in Stationary Boilers, Multiply the length of the boiler in inches by I the circumference in inches ; multiply the circumfer- ence of all the tubes or flues in inches by their length in inches. Add these two products and the areas of the ends in square inches together, and divide by 144. The quotient will be the number of square feet of heating surface. To find the horse-power, divide by 14 (14 square feet being a fair allowance for liorse- power in steam-boilers). 176 HAND-BOOK OF THE LOCOMOTIVE. PUNCHED AND DRILLED HOLES FOR THE SEAMS OP LOCOMOTIVE BOILERS. Punching rivet holes, according to Fairbairn’s ex- periments, is in itself a cause of weakness. Not only is the section of the plate in the line of strain reduced by the area of the holes, but the plate between the holes is not so strong per square inch as the solid plate. The excessive strain of the punch appears to dis- turb the molecular arrangement of the metal, and to start fractures which, in case of stay-bolts, often radiate in every direction, allowing corrosion to take* place, and ultimately causing the bolts to pull out of the plate. In eight experiments by Fairbairn, the highest strength of plate experimented upon was 61,579 pounds, and the lowest 43,805 pounds per square inch ; but with the same plates after punching, the strength per square inch varied between 45,743 pounds and 36,606 pounds. The average of the two experiments, therefore, showed a loss of 10,896 pounds per square inch, due to the jar and strain of punching, in addition to the loss of section through the holes. In the process of punching, through the ignorance or neglect of workmen, the holes do not come right by sometimes half their diameter, and are then drifted until the sheet is fractured, and the material partly destroyed. This habit cannot be too much repre- HAND-BOOK OF THE LOCOMOTIVE. 177 bended, and the use of drifts, although considered in- dispensable by many good boiler-makers, is productive of great evils. The result is when the rivets are driven it is almost impossible to make them fill the holes, and conse- quently an undue strain will come upon some of the rivets, while upon others there will be very little strain. In that case there is danger of shearing ofi* the rivet upon which the extra strain comes, and bringing a strain upon the adjoining holes, and thus starting a rupture, which will ultimately result in the destruc- tion of the boiler. The danger arising from this cause of rupture can be easily avoided by drilling, as the holes can be made to match exactly if the plates are drilled together, and therefore each rivet will do its due proportion of the work, and no greater strain will be thrown upon one than the others. Recent experiments authorized by the U. S. Gov- ernment at the Washington Navy Yard establish the fact that drilled holes for boiler seams are 6 per cent stronger than holes that are punched. In view of the above conclusions, it is very evident that the rivet holes for all longitudinal seams of steam boilers should be drilled. The curvilinear seams, being subjected to only about half the strain of the longitudinal, might be punched. It is also worthy of note that, while the punched plate is weaker than the drilled plate, the rivets in M 178 HAND-BOOK OF THE LOCOMOTIVE. the punched holes do not shear so easily as those in the drilled holes. This is probably due to the edges of the drilled holes being sharper and more compact, and consequently more capable of shearing than the edges left by a punch. Welding the seams of locomotive boilers, if practical, would be of great advantage, since the welded joint is practically twice as strong as the riveted joint; and since twice as much steam pressure is exerted on the longitudinal seams of the cylinder of a boiler as on its circular seams, the right propor- tion of strength would be preserved by welding the former and riveting the latter. The following advantages would be acquired by welding the seams of locomotive boilers; — 1st. It would cheapen the process of construction, by saving much of the time occupied in riveting, and all that consumed in caulking. 2d. The full strength of the plates being preserved, a thinner material would suf- fice, and, as a result, less dead weight would have to be transported. 3d. Double the pressure could be carried without increasing the weight of the boiler. 4th. There would be no double thickness of plate to promote unequal expansion. 5th. Where the greatest strain would occur, there would be no laps or joints, and consequently there would be no leakage. HAND-BOOK OF THE LOCOMOTIVE. 179 MACHINE AND HAND RIVETING FOR LOCOMO^ TIVE BOILERS. In the process of hand riveting, the heads are rarely finished till the iron is cool enough to crystallize or crack under the head by the heavy blows of the hammer, and if the material be not of superior quality, will frequently snap off under rough usage. Not so in machine riveting. As the piston is not limited in its movements, it will follow the rivet home, drawing the plates well together, filling the holes, and making the work equally good, whether the rivet is a half inch too long or a half inch too short, thus accomplishing what no workman could possibly do. As the riveting is done with a blow, and not by squeezing, the iron of the rivet is given no time to cool, by contact with the sheet, before it is forced into every crevice, and the hole completely filled. The heading is done on the “capping” system, thus gathering the metal together instead of scatter- ing it, as is the case with the hand hammer. The rivets driven by the Piston machine show the hole to be well filled all around, and not stretched to any appreciable extent, (not more so than in hand riveting,) while the rivet and plates are left soft and free from any crystallization. The shearing strain is less on machine -riveted joints than on those riveted by hand, on account of ISO HAND-BOOK OF THE LOCOMOTIVE. the compactness of the rivets in the holes, and the great friction between the sheets at the lap, induced by the power of the machine. Another great advantage of steam riveting is its quickness and cheapness. COMPARATIVE STRENGTH OP SINGLE AND DOUBLE RIVETED BOILER SEAMS. On comparing the strength of plates with their riveted joints, it will be necessary to examine the sectional areas, taken in a line through the rivet- holes with the section of the plates themselves. It is perfectly obvious that in perforating a line of holes along the edge of a plate, we must reduce its strength ; it is also clear that the plate so perforated will be to the plate itself nearly as the areas of their respective sections, with a small deduction for the irregularities of the pressure of the rivets upon the plate; or, in other words, the joint will be reduced in strength somewhat more than in the ratio of its section through that line to the solid section of the plate. It is also evident that the rivets cannot add to the strength of the plates, their object being to keep the two surfaces of the lap in contact. When this great deterioration of strength at the joint is taken into account, it cannot but be of the greatest importance that in structures subjected to HAND-jiOOK OF THE LOCOMOTIVE. ISl such violent strains as boilers, the strongest method of riveting should be adopted. To ascertain this, a long series of experiments were undertaken by Mr. Fair bairn. There are two kinds of lap-joints, — those said to be single riveted (Fig. 1), and those which are double riveted (Fig. 2). At first, the former were almost universally employed, but tSe greater strength of the latter has since led to their general adoption for all boilers intended to sustain a high steam pressure. A riveted joint generally gives way either by shearing ofi* the rivets in the middle of their length, or by tearing through one of the plates in the line of the rivets. In a perfect joint, the* rivets should be on the point of shearing just as the plates were about to tear; but in practice, the rivets are usually made slightly too strong. Hence, it is an established rule to employ a certain number of rivets per lineal foot. If these are placed in a single row, the rivet holes so nearly approach each other that the strength of the plates is much reduced ; but if they are arranged in two lines, a greater number may be used, and yet more space left between the holes, and greater strength and stiffness imparted to the plates at the joint. Taking the value of the plate before being punched at 100, by punching the plate loses 44 per cent, of its strength, and, as a result, single-riveted seams are 16 182 HAND-BOOK OF THE LOCOMOTIVE. equal to 56 per cent., and double-riveted seams to 70 per cent, of the original strength of the plate. It has been shown by very extensive experiments at the Brooklyn Navy Yard, and also at the Steven’s Institute of Technology, Hoboken, N. J., that double- riveted seams are from 16 to 20 per cent, stronger than single riveted seams — the material and work- manship being the same in both cases. Fig. 1. 1 (d Q 0 0 9 © 0 0 1 Fig. 2 . I O Q Q Q o Q Q 9 Taking the st^;pngth of the plate at . . 100 The strength of the double-riveted joint would then be 70 And the strength of the single-riveted joint would be 56 HAND-BOOK OF THE LOCOMOTIVE. 183 Rule for finding safe Worhing Pressure of any Boiler, Multiply the thickness of iron by .56, if single- riveted, and .70 if double-riveted ; multiply this pro- duct by 10,000 (safe load) ; then divide this last pro- duct by the external radius (less thickness of iron) : the quotient will be the safe working pressure in pounds per square inch. EXAMPLE. Diameter of boiler Thickness of iron 2 )^ 21 external radius .375 20.625 internal radius. Thickness of iron f = .375 .56 single riveted. 2250 1875 .21000 10000 safe load. 20.625 ) 2100 00000 ♦ 101.81 pounds safe working pressure. In the above rule 50,000 pounds per square inch are taken as the tensile strength of boiler iron, and one-fifth of that, or 10,000, as the safe load. Hence five times the safe working pressure, or 50,000 pounds, would be the bursting pressure. 42 inches. 184 HAND-BOOK OF THE LOCOMOTIVE. Rule for finding the Safe Worhing Pressure of Steel Boilers, Multiply thickness of steel by .56 if single riv- eted, and .70 if double riveted; multiply this pro- duct by 16,000 (safe load) ; then divide this last product by the external radius (less thickness of steel) : the quotient will be the safe working pres- sure in pounds per square inch. EXAMPLE. Diameter of boiler 44 inches. Thickness of steel J 2)44 22 external radius. .25 21.75 internal radius. Thickness of steel \ — .25 .70 double riveted. .175 16000 1050000 ^ 175 21.75)2800.000 128.73 safe working pressure. 80,000 being taken, in the above rule, as the ten- sile strength of steel, and one-fifth of that, or 16,000, as the safe load. Hence 80,000 would be the burst- ing pressure. HAND-BOOK OF THE LOCOMOTIVE. 185 Rule for finding the Safe External Pressure on Boiler Flues, Multiply the square of the thickness of the iron by the constant whole number, 806,300 ; divide this product by the diameter of the flue in inches ; di- vide the quotient by the length of the flue in feet ; divide this quotient by 3. The result will be the safe working pressure. EXAMPLE. Diameter, 13 inches. 13 diameter. Thickness, | of an inch. 10 length. I square = 130 3 390 A X 806,300=1^2®^ -j- 890 = 290.73 safe ’ 64 24960 external pressure. When pressure is exerted within a tube or cylin- der, the tube can only give way by the metal being torn asunder ; and the tendency of the strain is to cause the tube to assume the true cylindrical form. — the form of greatest resistance. But when pressure is exerted on the outside of a tube, the tendency of that pressure is to crush or flatten the tube. It is a well-known fact that iron of any strength, when formed into a tube, will bear a much greater strain to tear it asunder, if that pressure be applied 16* 186 HAND-BOOK OF THE LOCOMOTIVE. internally, than it will bear without crushing in when applied externally. It is also well known that a thin iron hoop will resist a large amount of tearing force ; but if that same hoop be placed as a prop under the weight exerted to tear it apart, it would be flattened and crushed out of form. The inner tubes of boilers are nothing more or less than a series of props ; but in the case of locomo- tive boilers the diameter of the tubes is so small that it is almost impossible to crush them. DEFINITIONS AS APPLIED TO BOILERS AND BOILER MATERIALS. Tensile strength is the absolute resistance which a body makes to being torn apart by two forces act- ing in opposite directions. Working Strength. — The term “ working strength’’ of materials is a certain reduction made in the esti- mate of the strength, so that when the instrument or machine is put to use it may be capable of resist- ing a greater strain than it is expected on the aver- age to sustain. Safe Working Pressure, or Safe Load. — The safe working pressure of steam boilers is generally taken as \ of the bursting pressure, whatever that may be. Elasticity is that quality which enables a body or boiler to return to its original form after having been distorted or stretched by some extreme force. HAND-BOOK OF THE LOCOMOTIVE. 187 EXPLANATION OP TABLE OP BOILER PRES- SURES ON POLLOWING PAGES. The horizontal column on top of the page, I, 00, 0, 1, etc., represents the number of the steel. The decimals, in the second horizontal column, are equal to the fractional parts of an inch in the third. The vertical column on the left hand side is the diameters in inches. All the other columns repre- sent pounds pressure per square inch. Example. — 24 -inch diameter, | steel, 289.03 pounds per square inch. Rule for finding the Aggregate Strain caused by the Pressure of Steam on the Shells of Locomotive Boilers, Multiply the circumference in inches by the length in inches ; multiply that product by the pressure in pounds per square inch. The result will be the ag- gregate pressure on the shell of boiler. EXAMPLE. Diameter of boiler Circumference of boiler. Length “ Pressure “ 131.9472 X 120 X 125 42 inches. 131.9472 “ 10 feet, or 120 • 125 lbs. ,979,208 pounds, or 989 tons. 2000 188 HAND-BOOK OF THE LOCOMOTIVE. TABLE OF SAFE INTERNAL PRESSURES FOR STEEL BOILERS. Birmingham Wire Gauge. 3 8 00 0 1 2 Thickness of Steel. .375 i .358 1 Scant. .340 ii .300 A .284 A External In. 24 lbs. per sq. in. 289.03 275.52 261.26 229.74 217.19 Diameter. 26 266.13 263.73 240.31 211.65 200.08 28 246.66 235.13 223.01 196.20 185.45 SO 229.74 219.00 207.80 182.85 172.99 32 215.04 205.06 194.15 171.21 161.91 34 202.10 192.74 182.85 160.95 152.22 36 190.63 181.82 172.50 151.86 143.23 Longitudinal Seams, Single Eiveted. 38 180.40 172.06 163.25 143.74 135.96 40 171.21 163.30 154.95 136.44 129.06 42 162.90 155.39 147.45 129.85 122.83 44 155.37 148.21 140.66 123.87 117.17 46 148.50 141.66 134.43 118.41 112.01 48 142.22 135.67 128.75 113.41 107.29 50 136.44 130.17 123.53 108.82 100.03 52 131.12 125.09 118.72 104.59 98.95 54 126.19 120.39 114.26 100.67 95.24 56 121.62 116.04 110.13 97.03 91.81 58 117.37 111.99 106.29 93.65 88.61 60 113.41 108.21 102.71 90.50 85.63 62 109.71 104.68 99.36 87.55 82.89 64 106.24 101.37 96.22 84.79 80.23 66 10i98 98.26 93.27 82.20 77.77 68 99.92 95.34 90.32 79.76 75.47 70 97.03 92.59 87.89 77.43 73.29 72 94.31 89.99 85.42 75.29 71.24 74 91.74 87.81 83.09 73.24 69.30 76 89.30 85.21 80.89 71.29 67.46 78 86.99 83.01 78.79 69.45 65.72 80 84.79 80.91 76.81 67.70 64.07 HAND-BOOK OF THE LOCOMOTIVE, 189 TABLE — {Continued) OF SAFE INTERNAL PRESSURES FOR STEEL BOILERS. Birmingham Wire Gauge. 3 4 5 6 7 8 Thickness of Steel. .259 iFull. .238 \ Scant .220 A .203 AFull .180 ASc’t. .166 AFull In lbs. per sq. in. Extern r1 24 197.63 181.13 167.33 154.18 136.44 124.91 EianneteT 26 182.13 167.09 154.24 142.13 125.80 115.10 28 168.88 154.95 143.04 131.83 116.70 106.85 30 157.42 144.45 133.36 122.92 108.82 99.65 32 147.42 135.29 124.91 115.14 101.94 93.36 34 138.60 127.22 117.47 108.28 95.88 87.81 36 130.80 120.05 110.86 102.20 90.50 82.89 ScEms, 38 123.82 113.65 104.96 96.76 85.69 78.49 Single 40 117.55 107.90 99.65 91.81 81.37 74.53 Liveted. 42 111.40 102.71 94.85 87.45 77.46 70.95 44 106.71 97.99 90.50 83.44 73.91 67.70 46 102.04 93.68 86.53 79.78 70.67 64.74 48 97.74 89.74 82.89 76.43 67.70 62.02 50 93.07 86.11 79.54 73.35 64.97 59.12 52 90.15 82.77 76.46 70.50 62.45 57.22 54 86.78 79.68 73.60 67.87 60.13 55.09 56 83.65 76.09 70.95 65.43 57.97 53.11 58 80.74 74.14 68.49 63.16 55.96 51.27 60 78.02 71.62 66.19 61.07 54.04 49.55 62 75.49 69.32 64.04 59.06 52.32 47.94 64 73.11 67.13 62.02 57.20 50.68 46.43 66 70.88 65.09 60.13 55.45 49.14 45.02 68 68.77 63.16 58.35 53.52 47.68 43.69 70 66.79 61.28 56.67 52.27 46.31 42.44 72 64.92 59.76 55.09 50.81 45.02 41.25 74' 63.16 58.00 53.59 49.43 43.80 40.13 76 61.48 56.47 52.17 48.12 42.64 39.07 78 59.90 55.01 50.83 46.88 41.54 38.061 80 58,39 53.63 49.55 45.65 40.50 37.11 190 HAND-BOOK OF THE LOCOMOTIVE, TABLE — {Contimied) OF SAFE INTERNAL PRESSURES FOR STEEL BOILERS. Birmingham Wire Gauge. I 00 0 1 2 Thi ckness of Steel. .375 1 .358 f Scant. .340 .300 A .284 A External Diameter. In. 24 lbs. per sq. in. 361.29 344.40 326.58 287.23 271.49 26 332.67 317.24 300.78 264.56 250.14 28 308.25 293.91 278.77 237.95 231.90 30 287.18 273.48 259.75 228.57 216.14 3'2 268.80 256.34 243.16 214.01 202.39 Longitudinal 34 252.63 240.93 228.57 201.19 190.28 Seams, 36 238.24 227.27 215.62 189.83 179.54 Double 38 225.50 215.08 201.07 179.67 169.95 Riveted. 40 214.01 204.13 193.69 170.55 161.28 Curvilinear 42 203.63 194.24 184.31 162.31 153.54 Seams, 44 194.21 185.26 175.80 154.83 146.47 Single , 46 181.21 177.08 168.04 148.Ui 140.02 Riveted.’ 48 177.77 169.55 160.94 141.77 134.12 50 170.55 162.71 154.41 136.03 128.69 52 163.90 156.40 148.01 130.73 123.68 54 157.74 150.49 142.83 125.84 119.05 56 152.03 145.05 137.61 121.29 114.76 58 146.72 139.99 132.86 117.01 110.76 60 141.77 135.26 128.38 113.13 107.03 62 137.14 130.85 124.20 109.44 103.55 64 132.80 126.74 120.27 105.99 100.29 66 128.73 122.83 116.53 102.75 97.22 68 124.90 119.18 113.13 99.70 94.34 70 121.29 115.74 109.86 96.85 91.62 72 117.89 112.49 106.78 94.11 89.05 74 114.67 109.42 103.87 91.55 86.63 76 111.62 106.51 101.11 89.12 84.33 78 108.73 103.76 98.49 86.72 82.15 80 105.99 101.14 96.01 84.63 80.08 HAND-BOOK OF THE LOCOMOTIVE. 191 ‘J? A B Xj “Fi — {Continued) OF SAFE INTERNAL PRESSURES FOR STEEL BOILERS. Birmingham Wire Gauge. 3 •4 5 6 7 8 Thickness .259 .238 .220 .203 .180 .166 of Steel. 1 Full. J Scant s^iFull ASc’t. /jFull In. lbs. per sq. in. Extf^rnal 24 247.06 226.62 209.16 192.72 175.63 156.14 Diameter. 26 227.67 208.87 192.80 177.66 157.25 143.98 28 211.10 193.69 178.80 164.78 145.87 133.57 30 196.78 180.57 166.71 153.65 136.03 124.57 32 184.28 169.75 156.14 143.92 127.43 116.70 T rfcn rv 34 173.27 159.06 146.84 135.35 119.85 109.77 36 163.50 150.07 138.58 127.75 113.13 103.61 38 154.73 142.07 131.20 120.95 107.12 98.11 jLJk) ti RivptGcl. 40 146.94 134.88 124.57 114.84 101.71 93.16 (In rvi 1 42 139.85 128.38 118.57 109.32 96.82 88.69 \y lA i V 1 i# Qpo rn « 44 133.42 122.48 113.13 104.30 92.39 84.64 Ssin (Xi)-lrf.|M COlS,T Inches. DIAM. OP TUBE. Cn OO CO 4. 4^ 4^ 00 00 OO *4 cc o ^ ^ bo O O «— 1 — to to ^ 05 to ^ CO CO ^45-^^0 05 4- 1—* Cl 00 to <35 O to O 00 05 Cl 00 CO O' OI M5^ CO K-i 4^ 4^ 4^ 00 00 OO CO o ^ bo . CT oi Cn Cn 05 05 O CO 05 00 1—* 5* *^*4xtobo^4- 05 CO CO 05 O CO h-* 05 to OO 00 1— ‘ Cn Cn CO to 4^ 4i- 4^ 4. CO CO CO o ^ 1 — bo <:o o o CO o CO CO CO CO CO CO CO OO Cl to O *^1 4»- 45- ^ O 4^ ^ O 00 <35 GO 1—1 4^- to Cn rfi- CO 00 4^ 4i. 4- 4^ CO 00 ^ ^ bo bi io o M- hfi. )+- 4^ CO CO OO Cn CO o Cn p* 00 Cl bo O M Cl Cl 00 H-* 4s. o CO CO CO CO CO o 00 Cn Oi 4^ 45>. 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Oi 05 - to CO 4^ Oi 05 CD CO ^ CD CO CD l-l, p * 4 , *0 *co b b CO 1 — ‘ Oi 0 4i, 0 CO 01 00 t-i 45 , t-* H-i SUPEEFICIAL AEEAS OF EXTEENAL SUEFACES OF TUBES OF VAEIOUS LENGTHS AND DIAMETEES IN SQUAEE FEET. HAND-BOOK OF THE LOCOMOTIVE. 209 P P ^ 2 to fcO to H-* l-i o to to to •-* V-* I-* 0 2 ® ^ oo|-j.;.|woclcn o pQ a-|r- cqr- C»|M cclw $ i'sg ^ 05 G5 Cn Cn H- • ^ 05 05 Cl Cl Oi *=^ 05 to bo CO CO bi CO O 05 to bo *45- I-* h-» 2 Cn CO O 00 O* CO 05 “-J 00 CD CD O [50 ^ to 05 t— O OC Oi CO O ^ Oi •. o 05 I— i k *CO O Cl *►-» to Cn to O 05 oc o 3 05 05 ^ ^ -4 OI CO to 1 — ‘ 05 GO o to 45- Cl ^ ^ 05 05 05 cn CO ■<1 05 05 05 Cl Cl bo CO CD cn O 05 to bo *45- *o *05 *to CO O 00 O ^ CO Hpi. H- * O 05 Cl 45- 45- CO to I—* •^5. 0« 05 --J 4- 4- GO to • 4^ CD 4^ CD CO 00 Cl ce I— CO -'1 Cl 0 00 Cl to O *<1 4^ s cD CD CD CD CD CD 00 ^ ^ 05 05 pi 1— ‘ ^ ^ p p p p *►-» k ‘to bo CO o b‘—‘kbob4- (—1 CD GO CO to 0 00 05 45 - H- CD h-‘ ^ to 05 1— Cl O s 00 Cl to 0 45 - 18 * 0 SUPEEFICIAL AEEAS OF EXTEENAL SUEFACES OF TUBES OF VAEIOUS LENGTHS AND DIAMETEES IN SQUAEE FEET. 210 HAND-BOOK OF THE LOCOMOTIVE. COMBUSTION OP FUEL IN LOCOMOTIVE FURNACES. In the locomotive furnace the main loss is sus- tained by the immense velocity in gases when the en- gine is under heavy strain. A nozzle that will give, under ordinary strain of engine, very satisfactory re- sults, will, under a heavy strain, tear out the fire, or reduce the temperature in gases to a degree where ignition is impossible. This velocity might, to some extent, be reduced by giving a larger grate-surface ; but in locomotives this cannot be done beyond a cer- tain limit, without inconvenience and loss in other parts of the machinery. A locomotive under 9,600 pounds strain — even if the influx of the air was well regulated — would still have a velocity in gases equal to 72 feet per second, or that of a storm. This is mainly owing to the small available grate-surface, which forces the cur- rent to accept a high velocity to fill the vacuum made in a given time. This may be in part avoided by hollow stay-bolts ; but, while their use is beneficial for the above-men- tioned purposes, they are productive of an evil almost as bad — that of receiving at times too much oxygen. Different devices have been resorted to, such as brick arches, water-tables, and deflectors, for the pur- pose of creating a recoil of the currents and increas- ing the friction, which may react on the grate-sur- HAND-BOOK OF THE LOCOMOTIVE. 211 face, thereby lessening the influx of air, and keeping the gases in contact with the fire for a longer period, in order to render the combustion of the fuel more •perfect. ’ But even these means are but imperfect, since the current is never constant, and the square surface of the nozzle always so, which must create imperfec- tions. The only radical mode of obviating these de- ficiencies, therefore, seems to be to regulate the influx of air according to requirements, which may be ef- fected by the exercise of care and good judgment. Light passenger engines always consume the fuel to a better advantage than the heavy freight engines, because their grate-surface is better proportioned to the work done, and in a light strain the proportion between the steam expelled and the air inhaled is nearer the correct one. Besides, there being no large quantity of air inhaled, there cannot be a very great velocity in the current ; consequently, the con- tact between the oxygen and the luminous gases is continued through the time necessary for complete combustion. It is well known that the air entering through the grate is twice, and in many cases three times, greater than the weight of the discharged steam, while the proportions between the steam discharged and the air inhaled ought in all cases to be about the same. The following rules, if carried out, would give most satisfactory results : 212 HAND-BOOK OF THE LOCOMOTIVE. First. — The difference in pounds between the steam exhausted and the air inhaled ought to be, in all cases, about the same. Second. — The bulk of fuel on the grate should always be in proportion to the fuel consumed. Third. — - The grate-surface ought to be as large as possible, to prevent a great velocity of current. Fourth. — The escape of gases from the furnace should be retarded, in order to prolong the contact between the oxygen and the gases, under a very high temperature. Fifth. — It should always be kept in mind that too much draft, though not so inconvenient, is just as injurious as not enough. MURDOCK’S LOCOMOTIVE— 1784. HAND-BOOK OF THE LOCOMOTIVE- 213 The above cut represents the smoke-box of the locomo- tive-boiler. A, A, arch-pipes ; B, double-cones ; D, pet- ticoat-pipe ; E, E, E, E, tubes ; C, C, exhaust-pots. SMOKE-BOX. The diameter of the smoke-box should, in all cases, be equal to the diameter of the boiler, and its length, from the face of the flue-sheet to the inside of the front door, about 11 times the length of the stroke of the engine, as the size of the smoke-box has much to do with the perfect combustion of the fuel. It is 214 HAND-BOOK OF THE LOCOMOTIVE. well known to engineers that the smaller the smoke- box the duller the fire ; and, on the other band, with a large smoke-box a large quantity of ai’r will be admitted to the fire, and the combustion of the fuel rendered more perfect. The smoke-box acts upon the fire as an air-vessel upon a pump — the larger it is, within certain limits, the more benefit will be derived from the fuel, as the exhaust does not jerk the fire or carry it out before it is consumed, as is generally the case when the smoke box is small, t SMOKE-STACKS. None of the forms of smoke-stacks now in use will answer for all classes of locomotives, consequently the style of smoke-stack best suited to any engine, or class of engines, will depend entirely on the char- acter of fuel to be consumed. For wood-burning engines the “bonnet” stack, having a diameter of from 5 to feet at the top, gives the most satisfac- tory results, as this form of stack insures a better draft, other things being equal, than any other pat- tern now in use. There may be other stacks that more efiectually prevent the emission of sparks, but it is accomplished at the expense of the draft. A large diameter at the height of the cone, and a large area of wire-netting, are necessary to insure good draft and prevent sparks being ejected in ob- jectionable quantities. HAITD-BOOK OF THE LOCOMOTIVE. 215 The inside pipe of the stack should be as high as practicable, and from 4 to diameters in length ; the bottom, where it joins the smoke-box, ought to be bell-mouthed for 6 or 6 inches up. The next 18 inches the pipe might be straight, and, as a rule, about one inch smaller than the diameter of the cylinders ; from that to the top the pipe should enlarge at the rate of 1 inch to the foot, the inside of the pipe to be as smooth as possible. This form of pipe offers the least resistance to the ascending column of steam, and produces a better draft than any other. Smoke-stacks for engines burning soft coal require a different construction at the top from those burn- ing wood, as they require less area around the cone ihan wood-burners. A stack that will clean itself well — that is, permit no lodgment of sparks or cinders in it or in the smoke-box — and at the same time throw no fire or large cinders, and has a good draft, will answer best for burning soft coal. The particular form for the top of the stack is not very material, yet that known as the diamond-shape top, with an annular space between the outer edges of the cone and wire netting of from 3 to 4 inches, gives very satisfactory results, as by this arrange- ment the gumming of the netting is avoided. For engines burning anthracite coal, the plain open stack, without cone or netting, gives the best satis- faction. 216 HAND-BOOK OF THE LOCOMOTIVE. EXHAUST-NOZZLE. Double exhaust-nozzles are in all cases preferable to single, on account of the back pressure produced by the single nozzle in the opposite cylinder at the moment and during the continuance of the exhaust. The top of the exhaust-nozzles should be as high as the third or fourth row of tubes from the bottom, and they should be as close as possible, and so directed that the exhaust steam will strike the centre of the cone at the top of the stack. Petticoat- or Clearance-pipe. — The petticoat- pipe, in good practice, is generally about I the diame- ter of the inside pipe of the stack, and to give satis- factory results, the top of the pipe ought to be about three inches below the top of the smoke-box, and the bottom the same height, or even with the top of the exhaust-nozzles. Grate-bars. — For wood- and soft coal-burning locomotives the old ordinary grate, with about J inch opening, gives very satisfactory results. For anthra- cite coal-burners the water-grate or water-tubes are extensively used, and seem to answer a very good purpose. Ash-pans. — The ash-pans for wood- and coal- burning engines should be as nearly air-tight as pos- sible when the dampers are closed. For wood-burning engines the depth from the bot- tom of the grates to the ash-pan ought to be about 9 HAND-BOOK OF THE LOCOMOTIVE. 217 inches; for soft coal-burners, not less than 10 inches; and for anthracite coal-burners 12 to 13, or even 14 inches. Dampers should be used front and back, and when shut, stand at an angle of about 35° from perpendic- ular ; the bottom of the ash-pan should be rounded up or raised about two inches at each end. Side doors are very convenient on coal-burners for cleaning the pans out. SAJETT-VALVES. The form and construction of this indispensable adjunct to the steam-boiler are of the highest impor- tance, not only for the preservation of life and prop- erty, which would, in the absence of this means of safety, be constantly jeopardized, but also to secure the boiler from undue strains and ultimate destruc- tion. Increasing the pressure to a dangerous degree, in a steam-boiler, would be impossible if the safety-valve were what it is supposed to be — a perfect means for liberating all the steam which a boiler may produce with the fires in full blast, and all other means for the escape of steam closed. Until such a safety- valve shall be devised and adopted into general use, safety from gradually increasing pressure must de- pend, to a certain extent, on the watchfulness of the engineer. 19 218 HAND-BOOK OF THE LOCOMOTIVE. It is supposed that a gradually increasing pressure can never take place if the safety-valve is in good working order, and if it have proper proportions. Upon this assumption, universally acquiesced in, when there is no accountable cause, explosions are attributed to the ‘‘ sticking’’ of the valves, or to “ bent valve-stems,” or “ inoperative ” valve-springs. As the safety-valve is the sole reliance in case of neglect or inattention on the part of the engineer, it is impor- tant to examine its mode of working closely. The safety-valve is designed on the assumption that it will rise from its seat under the statical pres- sure in the boiler, when this pressure exceeds the ex- terior pressure on the valve, and that it will remain off its seat sufficiently far to permit all the steam which the boiler can produce to escape around the edges of the valve. The ordinary safety-valve, as at present constructed, consists of a disc, which closes the outlet of a short pipe leading from the boiler. The area of the disc, or diameter of the valve, is usually determined from theoretical considerations, based on the velocity of the flow, or upon the results of experiments made to ascertain the area of orifice necessary for the flow of all steam a boiler can produce under a given pres- sure. The fact is recognized by engineers and con- structors that the real diameters of safety-valves must be greater than the theoretical orifices, because com- mon observation shows that the valves do not rise HAND-BOOK OF THE LOCOMOTIVE. 219 appreciably from tbeir seats ; and to make the outlet around the edges of the valve equal in area to the pipe, the valve should rise in all cases J its diameter. Every locomotive boiler should have two safety- valves, held in place by springs of sufficient elasticity to permit a lift of valve from its seat to give the re- quired area of opening for the escape of all the steam such boiler will make without a greater in- crease of pressure per square inch than five pounds over that at which the valve commences to rise. With the lift of one-sixteenth of an inch, at a pres- sure of 130 pounds per square inch, two three-inch valves would permit the escape of 12 cubic feet of steam per second, or nearly double the quantity that a boiler having 900 square feet of heating surface will supply. The springs connecting the safety-valves from levers with the boiler should be of sufficient length to permit a lift of the valves from their seats of at least of an inch with no greater addition of pres- sure than five pounds per square inch above the maximum pressure. The valve-seats of safety-valves should in all ases be made of brass, and the bearing or mitre on the valve face should not exceed of an inch. Every engineer should know that the safety-valves on his boiler are at all times .in good working order, and any engineer that would screw or weigh down his safety-valves for the purpose of increasing the 220 HAND-BOOK OF THE LOCOMOTIVE. pressure beyond that which he had reason to believe was safe, ought to be disqualified from ever taking charge of an engine again. TABLE SHOWING THE RISE OF THE SAFETY-VALVES, UNDER THE IN- FLUENCE OF DIFFERENT PRESSURES. ^‘tHE RISE OF THE VALVES IN PARTS OP AN INCH.” 12 lbs. 20 lbs. 35 lbs. 45 lbs. 50 lbs. ■h inch. inch. inch. inch. A iiich. 60 lbs. 70 lbs. 80 lbs. 90 lbs. jV inch. 1 xJi inch. yjy inch. jij inch. Or, taking average values, the rise for pressures from 10 to 40 pounds is 4^0 of an inch ; from 40 to 70 pounds and from 70 to 90 pounds, of an inch. These results show that the rise diminishes rapidly as the pressure increases — a result which is indicated by theory. The very small rise for pressure from 70 to 90 pounds, of an inch, is remarkable. Safety-valves are only a means of safety when well constructed and well cared for. Tests of safety-valves are very much needed, and should receive special attention from master mechan- ics, engineers, and steam users in general ; but tests, to be of any value, must be practical, and should be done by subjecting them to actual use on steam-boil- ers that were doing regular duty. HAND-BOOK OF THE LOCOMOTIVE. 221 STEAM-GAUGES. It is generally admitted that boiler explosions take place from different causes, and prominent among these causes are weakness, faulty construction, and over-pressure. It is to provide against the latter contingency that a good gauge is a real necessity wherever steam is employed ; but it is also a well- known fact that about one-half the gauges in use are either notoriously unreliable or completely worthless. Imperfectly graduated in the first place, and liable to become still further out of the way after a little use, many of them are really sources of danger instead of safety ; for their erroneous indications create a feeling of safety which sets the vigilance of the engineer to sleep. Even gauges bearing the most satisfactory test, when new, are oftentimes found to be utterly unreliable when placed upon boilers and subjected to the conditions to which all gauges are subjected when in use. Steam-gauges, like safety-valves, are only a means of safety when properly constructed, accurately grad- uated, and well cared for. A great many worthless steam-gauges are palmed off on steam users, the only proof of their efficiency being that they worked well under some experimen- tal test ; but when subjected to the conditions of constant use, they have proved utterly worthless. Practical tests of steam-gauges are very much needed. 19 * 222 HAND-BOOK OF THE LOCOMOTIVE. INSTRUCTIONS FOR THE CARE AND MAN- AGEMENT OP LOCOMOTIVE BOILERS. After heavy rains the water should be frequently run out of the boiler, in order to prevent the deposit of sediment on the sheets and flues. The deposits of scale and earthy matter should be removed from the crown-sheet as often as possible, in order to prevent the crown-sheet from being burnt or sprung. Every locomotive boiler should be provided with mud plugs on the sides of the shell on a level with the crown-sheet, for the purpose of washing out the mud with a hose from between the crown-bars. This could be done without weakening the boiler by rivet- ing an extra piece on the inside of the shell in the line of the holes. The accumulations of mud should be removed from the water-legs of the furnace and the barrel of the boiler as often as convenient, and the spaces thoroughly washed out with a hose. Boilers should never be blown out while hot, as the plates, flues, and braces retain sufficient heat to bake the deposits of mud into a hard scale, that be- comes firmly attached to their surface. The boiler should always be allowed to stand for several hours, or until it is cold, before the w^ter is run out ; the deposit of mud and scale will then be HAND-BOOK OF THE LOCOMOTIVE. 223 found to be quite soft, and can be easily washed out with a hose from all accessible places. There seems to be an impression in the minds of some engineers that blowing out a boiler under pres- sure has a tendency to remove the deposits of mud from the boiler, but experience has shown this to be a very grave mistake, as already shown. Boilers should never be filled with cold water while hot, as it has a very injurious effect, causing severe contraction of the seams and stays, which very often induces fracture of stays or leakage in the seams and tubes. Many boilers, well constructed and of good mate- rial, have been ruined by being blown out under a high pressure of steam, and then suddenly filled with cold water. Fractures, strained joints, and leaky tubes are gen- erally attributed to poor workmanship and poor ma- terial, when the mischief generally arises from the boiler being blown out under high steam, or filled with cold water while hot. The tubes of boilers being generally of thinner material than the shell, consequently cool and con- tract sooner ; for this reason the boiler should never be filled with cold water while the tubes are hot. If it is expected that the boiler will last to a good old age, ana render faithful service, it must be well cared for. 224 HAND-BOOK OF THE LOCOMOTIVE. FIREMEN ON LOCOMOTIVES. The general custom on nearly all the principal railroads in this country is to promote their firemen to the position of engineers, as it has been found, by experience, that locomotive engineers promoted from firemen were more reliable than machinists taken from the shops, unless the machinist has had sufficient experience as a fireman to make him well acquainted with the duties of engineers; and with this object in view, particular attention is paid to the selection of young men for firemen, and none but smart, active young men of good moral character and perfectly sober habits will receive any encouragement. After firing for about three years, if they give evi- dence of sufiicient capacity and carefulness, they are generally placed in the repair shop or round-house for one year, to enable them to learn the use of tools, but more particularly to make them acquainted and familiar with the construction of the locomotive en- gine and the manner of taking its machinery apart and putting it together again. If, at the end of the candidate’s fourth year, he has conducted himself properly, and given sufiicient evidence of his knowledge of the construction of a lo- comotive engine and its management to make a good engineer, he is promoted to a third-class engineer, with pay of twenty dollars per month less than that of a first-class engineer ; but if not found capable, he is dropped. HAND-BOOK OF THE LOCOMOTIVE. 225 After one year’s trial as third-class, if he still gives evidence of capacity and carefulness, he is advanced one grade higher, or to the position of second-class, with pay of ten dollars per month less than a first- class engineer. If, after the expiration of one year as a second- class engineer, he is qualified in everyway for a first- class engineer, he is advanced to that grade with first- class pay ; but if not found competent in every par- ticular, he is considered out of the regular order of promotion. In view of the above facts, it is perfectly obvious that every fireman who aspires to the position of a lo- comotive engineer ought to inform himself, as far as possible, on all questions connected with the care and management of the locomotive engine and boiler. He should improve every opportunity, make good use of leisure hours, connect himself with some public library, read scientific books, especially those treat- ing on subjects connected with his trade or calling, and endeavor to gain all possible information on all subjects connected with his business from the most reliable and practical sources. He should ask questions relating to his business of persons that he has reason to believe are competent to inform him, as he can do so without any sacrifice of feeling, being aware that he is not expected to know much about the duties of his calling at this stage of his apprenticeship. P 22G HAND-BOOK OF THE LOCOMOTIVE. He must remember that if the profession or call- ing of the locomotive engineer is to be dignified, the men that follow it for a trade must also be elevated — that it is not the work which gives dignity to the man, it is the character of the man that gives dignity to the vocation he pursues ; that it is only when one class of mechanics becomes equal to another in respect to intelligence, culture, and refinement, that their calling becomes equally dignified ; and, also, that the cultivation of the mind is the first step towards eminence in any trade or profession. He must understand that men’s labor is like mer- chandise, — the price is regulated, to a certain extent, by the demand, and if there are difierent qualities of the same article in the market, and purchasers are expected to pay as much for the inferior article as for the good one, they will very naturally take the best. Every fireman who goes on a locomotive with the intention of becoming an engineer should do so with the determination of making himself, if possible, a first-class engineer. But we know that it is not pos- sible for all to do this, as there is among firemen, as in all other trades and professions, a great many men who are totally unfit for the business — men that perhaps would succeed, to a certain extent, in some other pursuit, but who become a failure, and often a reproach on the profession they have adopted, simply for the reason that they made a mistake in the selection of a suitable trade. HAND-BOOK OF THE LOCOMOTIVE. 227 No fireman should make up his mind to become an engineer unless satisfied that he possesses the fol- lowing natural qualifications : 1. The power of long continued and unwearied at- tention, that he may be able to watch the road and his engine without the slightest relaxation, during the longest possible trip. 2. Endurance, both of body and mind, which in case of accidents and delays is often tested to the utmost. No man easily worn out has any business with runoing a locomotive. 3. Sharpness of sight, power of distinguishing colors of signals, soundness of hearing, and gener- ally that perfection of the senses which enables one to observe accurately objects at a distance. 4. Energy, decision, and presence of mind, the ab- sence of which in a runner will probably cause him to lose a train, or a life, or many lives in the course of his service. 5. Akin to the above is alertness of mind, which makes men alive to the slightest occurrences within reach of their senses, and is often strikingly devel- oped in hunters and men having charge of sentries and outposts in time of war. All the senses can be cultivated, sight excepted. 228 HAND-BOOK OF THE LOCOMOTIVE. FIRING. In estimating the relative merits of different loco- motives, it is always assumed that the fuel is burned under conditions with which the men who supply coal to the furnaces have nothing whatever to do — in short, that any man who can throw coals on a fire and keep his bars clean must be as good as any other man who can do, apparently, the same thing. But this conclusion is totally erroneous, as it is within the experience of every engineer that many engines now in operation throughout the coun- try consume from two to three times as much fuel, per horse-power, as is required in those that are more perfectly constructed and economically managed. In every case, a large proportion of this waste occurs in the furnace ; and while some of it is una- voidable, much of it is due to bad firing, and this bad firing is as often due to the want of knowledge as to carelessness and inattention. When the coal is in large lumps, so that the spaces between them are of considerable size, the depth may be greater than where the coal is small and lies compactly ; and where the draft is very strong, so that the air passes with great velocity over or through the fuel, there is not time for the carbonic acid to combine with and carry off the coal, and consequently a bed of greater depth may with propriety be used. Of course the depth in all cases must depend, to a HAND-BOOK OF THE LOCOMOTIVE. 229 certain extent, to the judgment of the fireman ; and to avoid unnecessary waste, he should see that the coal is evenly spread over the grate, and that there are no spaces through which streams of air pass without coming in contact with the fuel. Masses of clinkers are sometimes carelessly allowed to accumulate on the grate ; these, being incombusti- ble, allow air to pass over them without producing any result ; and when this air mixes with the pro- ducts of combustion, it lowers the general temperature, and so detracts from the efficiency of the fuel. All clinker and incombustible matter should be removed as soon as possible, and the coal should be spread evenly and compactly — no thin places on one part of the grate and large heaps on another. Then, as the air costs nothing, while fuel is quite expensive, we must be very careful that none of the latter is allowed to pass out of the furnace without being fully neutralized. But while it would be un- fair to expect ordinary engineers or firemen to have a minute acquaintance with the higher departments of chemistry, it is not too much to ask that they should have a moderate familiarity with the princi- ples of combustion, and other facts and laws relating to heat, as well as such ordinary mechanical problems and theorems as are necessary to the performance of their duties in a safe, practical, and economical manner. 20 230 HAND-BOOK OF THE LOCOMOTIVE. RUE’S "LITTLE GIANT" INJECTOR. HAND-BOOK OF THE LOCOMOTIVE. 231 THE INJECTOR. Of all the inventions of the mechanic and the scientist, nothing seemed to the uneducated to ap- proximate so nearly to perpetual motion as the instrument now in general use as a boiler-feeder on locomotives and stationary engines, and known as the injector, and which, from common use, no longer excites the wonder even of those who do not under- stand its mode of operation. It consists of a slender tube, called the steam-tube, through which steam from the boiler passes to another or inner tube, called the receiving-tube. The latter tube conducts a current of water from a pipe into the body of the injector. Opposite the mouth of this second tube, and detached from it, is a third fixed tube, called the delivery-tube. This tube is open at the end facing the water-supply, and leading from the injector to the boiler. The action of the injector is that which Venturi, in the beginning of the present century, designated as the “ lateral action of fluids,’’ and, having been investigated by Dr. Young, in 1805, was proposed by Nicholson, in 1806, for forcing water. The action is identical to that of the steam-jet, or blower-pipe, in the chimney of the locomotive. The principle is that steam, being admitted to the inner tube of the injector, enters the mouth of a combining-tube, in the form of a jet, near the top of the inlet water- 232 HAND-BOOK OF THE LOCOMOTIVE. pipe. If the level of the water be below th6 injector, the escaping jet of steam, by its superficial action (or friction) upon the air around it, forms a partial vacuum in the combining-tube and inlet-pipe, and the water then rises in virtue of the external pressure of the atmosphere. Once risen to the jet, the water is acted upon by the steam in the same manner as the air had been, seized and acted upon in first form- ing the partial vacuum into which the water rose. Gifiard’s discovery was that the motion imparted by a jet of steam to a surrounding column of water was sufficient to force it into the boiler from which the steam was taken, and, indeed, into a boiler work- ing at even a higher pressure. But the most im- portant improvement ever heretofore made in the injector was made in 1868, by Samuel Rue, by which the injector, with steam of from 80 to 90 pounds’ pressure, is capable of forcing water against a pressure of from 400 to 450 pounds per square inch. This extraordinary accumulation of power may be explained as follows : The velocity with which steam — say at 60 pounds’ pressure to the square inch — flows into the atmosphere is about 1700 feet per sec- ond. Now suppose that steam is issuing, with the full velocity due to the pressure in the boiler, through a pipe an inch in area, the steam is condensed into water, at the nozzle of the injector, without suffering any change in its velocity. From this cause its bulk will be reduced, say 1,000, and, therefore, its area HAND-BOOK OF THE LOCOMOTIVE. 233 of cross-section — the velocity being constant — will experience a similar reduction. It will then be able to enter the boiler again by an orifice of that by which it escaped. Now it will be seen that the total force expended by the steam through the pipe, on the area of an inch, in expelling the steam jet, was concentrated upon the area jo^o'o^^ of an inch, and, therefore, was greatly superior to the .opposing pressure exerted upon the diminished area. RUE’S "LITTLE GIANT" LETTER "B" INJECTOR. How to put on Letter Injector. — Put the injector in a horizontal position above the foot-board, and within easy reach of the engineer, using as short a length of pipe for “ steam and deliverance to the boiler ” as possible. Put an ordinary globe or 20 * 23 i HAND-BOOK OF THE LOCOMOTIVE. angle-valve on the steam supply-pipe, for starting, etc., taking the steam from the highest part of the boiler, and attaching it to the swivel marked “steam.’’ Attach the water supply-pipe to the swivel marked “ water,” putting an ordinary water-cock on the supply-pipe near to the injector. A good supply of water must be had, and if taken from a tank, give it a good fall. The mouth of the pipe should be enlarged, and a screen with small meshes placed over it to keep out dirt; if the supply-pipe be over ten feet in length, or if the water come from a hydrant, or any source that makes a pressure, and the supply is not at a regular pressure, the pipe should be one size larger than the swivel marked “water,” which can be done by putting on a reducer. At this point turn on your steam and water, and let them flow through the injector, to see if the pipes and injectors are free from dirt. Then attach the “ delivery-pipe ” to the swivel marked “ to boiler.” Method of Working Letter Injector. — Turn on the water, and, when it flows from the overflow, turn on the steam, slowly at first, until it catches the water, then turn on full head, and push the lever M slowly either forwards or backwards, as seems requisite, until neither steam nor water shows at the overflow. Failure to work will always show at the overflow, and when the point is,ascertained at which the lever is to be set for the steam pressure to be carried, it can be regulated, and then left to stand at that posi- HAND-BOOK OF THE LOCOMOTIVE. 235 tion when tlie steam and water are shut off. The lever is only used to regulate the proportionate amounts of water and steam. But when water is to be lifted by this injector, a small steam-pipe leading from the boiler and furnished with a valve that opens with a quick motion, is at- tached to the swivel “ P,” by means of which a steam- jet is thrown into the tube “ R,’’ and the water lifted. But at this point it is necessary to examine the tube in order to ascertain if the suction is good, or if it lifts the water readily, and if so, the steam supply- pipe can be attached to the swivel marked “ steam,’’ and the injector cleared of any dirt that may have collected in the boiler ; then the delivery-pipe to the boiler may be attached to the swivel marked “ to boiler.” Great care should be taken to see that the supply-pipe through which the water is lifted is per- fectly air-tight, as any leak in the pipe will interfere with the working of the injector. Washers should never be used in the swivels connecting the pipes to the injector, as the joints are all ground. The performances of this little machine are actu- ally astonishing, as, with a steam pressure of 80 or 90 pounds per square inch on the boiler to which it is attached, it will successfully force water into other boilers under a pressure of from 400 to 450 pounds per square inch. It can be regulated to supply any required quantity of water, and is equally reliable when it is used every day or not more than once a year. 236 HAND-BOOK OF THE LOCOMOTIVE. Hints to Locomotive Engineers. — The “Little Giant’’ injector can be set to feed a steady stream, but in some cases it may be advisable to set it so that the boiler will lose a small quantity of water in running between stations ; then, by keeping the in- jector at work while the engine is standing at the station, a good supply of water will be obtained to run to the next station. This plan, properly carried out, will make a great saving in fuel, and also have a tendency to prevent boiler explosions, as, when the engine is stopped, the whole heat of the fire is thrown against the sides of the furnace and the crown- sheet, which, if the circulation of the water is not kept up, will soon become overheated, and may possi- bly cause an explosion. The injector, as a boiler-feeder, possesses advan- tages in point of economy over all other devices, as the steam that is admitted to the injector, from the boiler, returns to the boiler, carrying with it more than twenty times its weight of water. Not a drop of water is lost, nor a particle of steam wasted. It occupies but little space, requires no oil, packing, or any special care, and very little, if any, repairs. It can be set up in almost any position ; but, where circumstances will permit, a horizontal position is very much to be preferred. On locomotives, it should invariably be placed above the foot-board, and within easy reach of the engineer. There should be one of these injectors attached HAND-BOOK OF THE LOCOMOTIVE. 237 to every locomotive, as they are always available and reliable in case of stoppage, accident, or deten- tion from any cause whatever. Therefore every engineer should encourage their introduction on locomotives, steamships, stationary and portable steam-boilers. TABLE OF CAPACITIES OF KUE’S LITTLE GIANT INJECTOK. Size of Injectors. Size of Pipe Connections. Pressure of steam in lbs. Gallons per hour. Nominal Horse-Power. 0 i 90 60 4 to 8 1 i 90 90 6 “ 12 2 i 90 120 8 “ 20 3 1 90 300 20 “ 40 4 1 90 600 40 •“ 80 5 I4 90 900 60 “ 120 6 li- 90 1200 80 “ 160 7 90 1620 140 “ 225 8 2 90 2040 200 “ 275 9 2 90 2480 250 “ 350 10 2 90 3000 800 “ 400 12 2^ 90 3600 350 “ 500 In ordering injectors, it should be always stated whether the connecting-pipes are copper, brass, or iron, and whether for locomotive or stationary boilers. 238 HAND-BOOK OF THE LOCOMOTIVE. SIGNALS. A red flag by day, a red lantern by night, or any signal violently given, are signals of danger, on perceiving which the train must be brought to a full stop as soon as possible, and not proceed until it can be done with safety. Two red flags by day, and two red lanterns by night, placed on the front of an engine, indicate that the engine is to be followed by an extra train. A lantern raised and lowered vertically is a signal for starting ; when swung at right angles, or across HAND-BOOK OF THE LOCOMOTIVE. 239 the track, to stop ; when swung in a circle, back the train. A sweeping parting of the hands, on a level with the eye, is a signal to go ahead. A downward motion of one hand, with extended arm, to stop. A beckoning motion of one hand, to back. One short sound of the whistle is the signal to apply brakes ; two, to let go brakes ; three, to back up; four, to call in the flagman; five, for road crossings. One stroke of the alarm-bell signifies stop ; two, to go ahead ; three, to back up. WRECKING TOOLS. A A represents a truck-axle and wheels. C is a bar of iron, about two by four inches, bent like the bail of a bucket, with a hook or turn on each end of it large enough to hook over an axle close to each 240 HAND-BOOK OF THE LOCOMOTIVE. wheel, and which is used in pulling cars on the track when they may be off on one side, or for “ straight- ening the track toward the point to which it is de- sired to pull the car, and pulling the car by this ‘‘bail” the track is kept diiectly in the line of draft. There is a loose link, B, on the “bail,” C, into which the hook or draft-rope is attached. When this link is put into the centre notch of the bail the axle of the truck will be held at right angles to the rope ; and when put into the notch on either side of the centre, the axle will be held at a corresponding angle to the line of draft of the rope. ^ By this bail a car (or truck, or pair of wheels) can be pulled in almost any direction by putting it on the front axle and drawing by the link, B, and the hook, A, and “ chaining” the back truck so as to keep it in line with the body of the car. The monkey-jack, K, generally renders good service in the case of wrecks. Portable frogs, made of heavy boiler plate, with flanges and clasps to take hold of the rail, are some- times used for placing cars on the track in case of a wreck. USEFUL NUMBERS IN CALCULATING WEIGHTS, MEASURES, ETC. Feet multiplied by .00019 equals miles. Yards n .0006 (t miles. Links (( .22 (( yards. Links (t .66 (( feet. Feet <( 1.615 (( links. HAND-BOOK OF THE LOCOMOTIVE. m Sqoare inches multiplied by .007 equals squai e feet. Circular inches .00546 tf square feet. Square feet (( .111 ft square yds. Acres f( 4840 ft square yds. Square yards (( .0002066 ft acres. Width in chains ft .8 ft acres per m. Cube feet ft .037 ft cube yards. Cube inches ft .00058 ft cube feet. U. S. bushels ff .0461 ft cube yards. U. S. bushels ft 1.2444 ft cube feet. U. S. bushels ft 2150.42 ft cube inches. Cube feet ft .8036 ft U. S. bushes. Cube inches ft .000465 ft U. S. bushes. U. S. gallons t( .13367 ft cube feet. U. S. gallons ft 231 ft cube inches. Cube feet ft 7.48 ft U. S. galls. Cylindrical feet ft 5.874 ft U. S. galls. Cube inches ft .004329 ft U. S. galls. Cylindrical inches ft .0034 ft IT. S. galls. Pounds ft .009 tf cwt. Pounds ft .00045 ft tons. Cubic foot of water ft 62.5 tf lbs. avoird. Cubic inch of water ft .03608 tf lbs. avoird. Cylindrl foot of water ft 49.1 ft lbs. avoird. Cylindr’l inch of water ft .02842 ft lbs. avoird. U. S. gallons of water ft 13.44 ft 1 cwt. U. S. gallons of water ft 268.8 . ft 1 ton. Cubic feet of water ft 1.8 ft 1 cwt. Cubic feet of water Sf 35.88 ft 1 ton. Cylindr^l foot of water ft 5.875- ft U. S. galls. Column of water, 12 in. high, 1 in. diameter ft .341 lbs. 183.346 circular inches ft 1 square ft. 2200 cylindrical inches ff 1 cubic foot French metres multiplied by 3.28 ft feet. Kilogrammes ‘‘ 2.205 ft avoird. lbs. Grammes “ .002205 ft avoird. lbs. 21 Q 242 HAI^D-BOOK OF THE LOCOMOTIVE. MENSURATION OP THE CIRCLE, CYLINDER, SPHERE, ETC. 1. The circle contains a greater area than anj other plain figure bounded by an equal perimeter oi outline. 2. The areas of circles are to each other as the squares of their diameters. 3. The diameter of a circle being 1, its circum- ference equals 3.1416. 4. The diameter of a circle is equal to .31831 of its circumference. 5. The square of the diameter of a circle being 1, its area equals .7854. 6. The square root of the area of a circle multi- plied by 1.12837 equals its diameter. 7. The diameter of a circle multiplied by .8862, or the circumference multiplied by .2821, equals the side of a square of equal area. 8. The sum of the squares of half the chord and versed sine, divided by the versed sine, the quotient equals the diameter of corresponding circle. 9. The chord of the whole arc of a circle taken from eight times the chord of half the arc, one-third of the remainder equals the length of the arc ; or, 10. The number of degrees contained in the arc of a circle, multiplied by the diameter of the circle and by .008727, the product equals the length of the arc in equal terms of unity. HAND-BOOK OF THE LOCOMOTIVE. 243 11. The length of the arc of a sector of a circle multiplied by its radius, equals twice the area of the sector. 12. The area of the segment of a circle equals the area of the sector, minus the area of a triangle whose vertex is the centre, and whose base equals the chord of the segment ; or, 13. The area of a segment may be obtained by dividing the height of the segment by the diameter of the circle, and multiplying the corresponding tab- ular area by the square of the diameter. 14. The sum of the diameters of two concentric circles multiplied by their difference and by .7854, equals the area of the ring or space contained between them. 15. The sum of the thickness and internal diameter of a cylindric ring multiplied by the square of its thickness and by 2.4674, equals its solidity. 16. The circumference of a cylinder multiplied by its length or height, equals its convex surface. 17. The area of the end of a cylinder multiplied by its length, equals its solid contents. 18. The internal area of a cylinder multiplied by its depth, equals its cubical capacity. 19. The square of the diameter of a cylinder mul- tiplied by its length, and divided by any other re- quired length, the square root of the quotient equals the diameter of the other cylinder of equal contents or capacity. 244 HAND-BOOK OF THE LOCOMOTIVE, 20. The square of the diameter of a sphere mul- ’ tiplieJ by 3.1416, equals its convex surface. 21. The cube of the diameter of a sphere multi- plied by .5236, equals its solid contents. 22. The height of any spherical segment or zone multiplied by the diameter of the sphere of which it is a part, and by 3.1416, equals the area or convex surface of the segment ; or, 23. The height of the segment multiplied by the circumference of the sphere of which it is a part, equals the area. 24. The solidity of any spherical segment is equal to three times the square of the radius of its base, plus the square of its height, and multiplied by its height and by .5236. 25. The solidity of a spherical zone equals the sum of the squares of the radii of its two ends, and one- third the square of its height multiplied by the height and by 1.5708. 26. The capacity of a cylinder 1 foot in diameter and 1 foot in length equals 5.875 of a United States gallon. 27. The capacity of a cylinder 1 inch in diameter and 1 foot in length equals .0408 of a United States gallon. 28. The capacity of a cylinder 1 inch in diameter and 1 inch in length equals .0034 of a United States gallon 29. The capacity of a sphere 1 foot in diameter equals 3.9168 United States gallons. HAND-BOOK OF THE LOCOMOTIVE. 245 30. The capacity of a sphere 1 inch in diameter equals .002267 of a United States gallon ; hence, 31. The capacity of any other cylinder in United States gallons is obtained by multiplying the square of its diameter by its length, or the capacity of any other sphere by the cube of its diameter, and by the number of United States gallons contained as above in the unity of its measurement. TABLE OF DECIMAL EQUIVALENTS TO THE FRACTIONAL PARTS OP A GALLON OR AN INCH. (The inch or gallon being divided into 32 parts.) 1 tn a a *o o a 05 in a a O p 05 05 05 eS ft O o o ft a ft •S o o ft a .08125 sV 1 1 T 1 8 .53125 ii 17 2i .0625 tV 2 1 2 1 T .5625 18 4f 2i .09375 3 3^ 3 i 3 :§• .59375 1 9 3 2 19 4f 08 .125 1 4 1 i .625 5 8 20 5 2i .15625 A 5 li 5 8 .65625 2 1 JJ 21 2f .1875 6 3 T .6875 ■fi 22 5f 2f .21875 A 7 If 7 8 .71875 If 23 5| .25 8 2 1 .75 f 24 6 3 .28125 A 9 .78125 If 25 ^i .3125 TF 10 .8125 ft 26 H H .34375 11 2| If .84375 If 27 6i 3f .375 f 12 3 H .875 28 7 3i .40625 M 13 3i If .90625 2 9 29 H 3f .4375 tV 14 H H .9375 1 5 T6 30 n 3f .46875 if 15 3| H .96875 3 1 32 31 n 3t .5 16 4 2 1.000 1 32 8 4 21 * 246 HAND-BOOK OF THE LOCOMOTIVE. In multiplying decimals it is usual to drop all but the first two or three figures. Application. — Kequired, the gallons in any cylin- drical vessel. Suppose a vessel 9^ inches deep, 9 inches diameter, and contents 2.6163 — that is, 2 gallons and ^ gallon. Now to ascertain this decimal of a gallon refer to the above table for the decimal that is nearest, which is .625, opposite to which is |th of a gallon, or 20 gills, or 5 pints, or 2i quarts ; consequently the vessel contains 2 gallons and 5 pints. Inches. — To find what part of an inch the .708 is refer to the above table for the decimal that is nearest, which is .71875, opposite to which is ||, or nearly f of an inch. TABLE ON FOLLOWING PAGES CONTAINING THE DIAMETERS, CIRCUMFERENCES, AND AREAS OF CIRCLES, AND THE CONTENTS OF EACH IN GALLONS AT 1 FOOT IN DEPTH. 1. Eequired, the circumference of a circle, the di- ameter being 5 inches. In the column of circumferences, opposite the given diameter, stands 15.708 inches, the circumference re- quired. 2. Kequired, the capacity, in gallons, of a cylinder, the diameter being 6 feet and depth 10 feet. In the fourth column from the given diameter HAND-BOOK OF THE LOCOMOTIVE. 247 stands 211.4472, being the contents of a cylinder 6 feet in diameter and 1 foot in depth, which being multiplied by 10, gives the required contents, 2,114i gallons. 3. Any of the areas in feet multiplied by .08704, the product equals the number of cubic yards at 1 foot in depth. 4 . The area of a circle in inches, multiplied by the length or thickness in inches and by .263, the product equals the weightr in pounds of cast-iron. (See page 245 for Decimal Equivalents to the fractional parts of a gallon and an inch.) TABLE OF DIAMETERS, CIRCUMFERENCES, AND AREAS OF CIR- CLES, AND THE CONTENTS OF EACH IN GALLONS AT 1 FOOT IN DEPTH. Diameter. Circumference, Inches. Area, Inches. Gallons. lin. 3.1416 .7854 .04084 2 “ 6.2832 3.1416 .16333 3 9.4248 7.0686 .36754 4 “ 12.566 12.566 .65343 5 15.708 19.635 1.02102 6 ‘‘ 18.849 . 28.274 1.47025 7 21.991 38.484 2.00117 8 25.132 50.265 2.61378 9 “ 28.274 63.617 3.30808 10 31.416 78.540 4.08408 11 “ 34.557 95.033 4.94172 248 HAND-BOOK OF THE LOCOMOTIVE. TABLE — {Continued) OF DIAMETEKS, CIRCUMFERENCES, AND AREAS OF CIRCLES, AND THE CONTENTS OF EACH IN GALLONS AT 1 FOOT IN DEPTH. Diameter. Circumference. Area in Feet. Gals., 1 ft. in Depth. 1 ft. 3 ft. l|in. .7854 5.8735 2 6 “ 3| “ 3,1416 23.4940 3 ‘‘ 9 5 7.0686 52.8618 4 12 6| 12.5664 93.9754 5 15 8J 19.6350 146.8384 6 18 lOJ 28.2744 211.4472 7*“ 21 Hi 38.4846 287.8032 8 25 “ li 50.2656 375.9062 9 28 “ Si 63.6174 475.7563 10 31 5 78.5400 587.3534 11 “ 34 6f 95.0334 710.6977 12 “ 37 8i ‘‘ 113.0976 848.1890 13 40 10 132.7326 992.6274 14 43 Ilf ‘‘ 153.9384 1151.2129 15 47 li 376.7150 1321.5454 16 50 3i 201.0624 1503.6250 17 53 4i 226.9806 1697.4516 18 56 6i 254.4696 1903.0254 19 59 81 283.5294 2120.3462 20 62 91- 314.1600 2349.4141 21 “ 65 Ilf 346.3614 2590.2290 22 “ 69 ‘‘ If 380.1336 2842.7910 23 “ 72 3 415.4766 3107.1001 24 75 4i 452.3904 3383.1563 25 78 6f 490.8750 3670.9596 26 81 “ 8f 530.9304 3970.5098 27 84 9f ‘‘ 572.5566 4281.8072 28 87 ‘‘ Ilf “ 615.7536 4604.8517 29 “ 91 11 660.5214 4939.6432 30 94 “ 2i 706.8600 5286.1818 HAND-BOOK OF THE LOCOMOTIVE. 249 TABLE SHOWING THE WEIGHT OF WATER IN PIPE OF VARIOUS DIAMETERS 1 FOOT IN LENGTH. Diameter in Inches. Weight in Pounds Diameter in Inches. Weight in Pounds. Diameter in Inches. Weight in Pounds. 3 3 121 51 22} 172} 3} Si 12} 53} 23 180} Si 4J 12| 55} 23} 188} 3| 4i 13 57} 24 196} 4 5i 131 59| 24} 204} 6^ 18J 62} 25 213 4J 7 13| 64} 25} 221} 4i 7i 14 66| 26 230} 5 . Si 141 69} 26} 239} 5i n 141 71} 27 248} 5i lOJ 14| 74} ■ 27} 2571 5| lli 15 76} 28 267} 6 12J- 15} 79} 28} 276} isi 15} 82 29 286} 6} m 15| 84} 29} 296} 6| m 16 87} 30 306} 7 16| 16} 90 30} 317} 7i 18 16} 92} 31 327} 7i 19} 16| 95} 31} 338} 7i 20i 17 98} 32 349 8 21| 17} 101} 32} 360 8i 23} 17} 104} 33 371} Si 24} 171 107} 33} 382} Si 26 18 110} 34 394 9 27} 18} 113} 34} 405} 9} 29} 18} 116} 35 417} 9} 30f 18| 119} 35} 429} 9| 32} 19 123 36 441} 10 34 19} 126} 36} 454 lOJ 35} 19} 129} 37 466} lOJ 37} 19| 132 37} 479} 10| 39} 20 136} 38 492} 11 41} 20} 143} 38} 505} m 44} 21 150} 39 518} m 45 21} 157} 39} 531} Hi 47 22 165 40 545} 12 49 250 HAND-BOOK OF THE LOCOMOTTVK, RULES. Rule. — For finding the Quantity of Water in a Steam-boiler or any Cylindrical Vessel in Cubic Inches, — Multiply the internal area of the head or base in inches by the length in inches ; the product will be the number of cubic inches of water in the boiler. Divide this product by 1728, and the quotient will be the number of cubic feet of water in the boiler or cylinder. Rule. — To find the Requisite Quantity of Water for a Boiler, — Add 15 to the pressure of steam per square inch; divide the sum by 18; multiply the quotient by .24; the product is the quantity in U. S. gallons per minute for each horse-power. Rule. — To find the Height of a Column of Water to supply a Steam-boiler against any Pressure of Steam required, — Multiply the pressure, in pounds, upon a square inch of boiler, by 2.5 ; the product will be the height in feet above the surface of the water in the boiler. Rule. — To find the Time a Cylindrical Vessel will take in filling when a known Quantity of Water is going in and a known Quantity of that Water is going out in a given time. — Divide the contents of the cistern, in gallons, by the difference of the quantity going in and the quantity going out per hour, and the quotient is the time in hours and parts that the cistern will take in filling. HAND-BOOK OF THE LOCOMOTIVE. 251 Pressure of Water. — The weight of water or of other liquids is as the quantity, but the pressure ex- erted is as the vertical height. Fluids press equally in all directions; hence, any vessel containing a fluid sustains a pressure equal to as many times the weight of the column of greatest height of that fluid as the area of the vessel is to the sectional area of the column. Lateral Pressure. — The lateral pressure of water on the sides of a vessel in which it is contained is equal to the product of the length multiplied by half the square of the depth and by the weight of the water in cubic unity of dimensions. Discharge of Water. — In circular apertures in a thin plate on the bottom or side of a reservoir, the issuing stream tends to converge to a point distant at about i its diameter from outside the orifice, reducing the quantity nearly |ths from the quantity due to the velocity corresponding to the height. When water issues from a short tube, the flow is less contracted than in the former case, as 16 to 13. With a conical aperture, whose greater base is the aperture, the height of the frustrum being half the diameter of the aperture, and the area of the small end to the area of the large end as 10 to 16, there will be no contraction of the vein. Hence this form gives the greatest flow. The quantity of water discharged during the same time by the same orifices under difterent heads, are 252 HAND-BOOK OF THE LOCOMOTIVE. nearly as the square roots of the corresponding heights of the water in the reservoir above the sur- face of the orifices. Small orifices, on account of friction, discharge pro- . portionately less fluid than those which are larger and of the same figure, under the same pressure. Circular apertures are the most efficacious, having less rubbing surface under the same area. If the cylindrical horizontal tube through which water is discharged be of greater length than the diameter, the discharge is much increased — can be increased, to advantage, to four times the diameter of the orifice. RULES FOR FINDING THE ELASTICITY OF STEEL SPRINGS. Rule I. — To find the Elasticity of a given Steel- plate Spring, — Breadth of the plate in inches multi- plied by the cube of the thickness in inch, and by the number of plates ; divide the cube of the span in inches by the product so found, and multiply by 1.66. The result equals the elasticity in of an inch per ton of load. Rule 2. — To find Span due to a given Elasticity, and the Number and Size of Plate. — Multiply the HAND-BOOK OF THE LOCOMOTIVE. 253 elasticity in sixteenths per ton, by the breadth of the plate in inches, and divide by the cube of the thick- ness in inches, and by the number of plates ; divide by 1.66, and find the cube root of the’ quotient. The result equals the span in inches. Rule 3. — To find the Number of Plates due to a given Elasticity, the Span and Size of the Plates, — Multi- ply the cube of the span in inches by 1.66 ; multiply the elasticity in sixteenths by the breadth of the plate in inches, and by the cube of the thickness in sixteenths ; divide the former product by the latter. The quotient is the number of plates. Rule 4. — To find the Working Strength of a given Steel-plate Spring, — Multiply the breadth of plate in inches by the square of the thickness in sixteenths, and by the number of plates ; multiply also the work- ing span in inches by 11.3 ; divide the former pro- duct by the latter. The result equals the working strength in tons burden. Rule 5. — To find the Span due to a given Strength and the Number and Size of Plate, — Multiply the breadth of the plate in inches by the square of the thickness in sixteenths, and by the number of plates; multiply, also, the strength in tons by 11.3, divide the former product by the latter. The result equals the working span in inches. Rule 6. — To find the Number of Plates due to a given Strength, Span and Size of Plate, — Multiply the strength in tons by span in inches, and divide by 22 254 HAND-BOOK OF THE LOCOMOTIVE. 11.3 ; multiply also the breadth of plate in inches by the square of 4he thickness in sixteenths ; divide the former product by the latter. The result equals the number of plates. The span is that due to the form of the spring loaded. Extra thick plates must be replaced by an equivalent number of plates of the ruling thickness, before applying the rule. To find this, multiply the number of extra plates by the ruling thickness ; con- versely, the number of plates of the ruling thickness to be removed for a given number of extra plates, may be found in the same way. Springs were applied to locomotives in 1830, by T. Hackworth. CBOSSCUPa, WEST.PHILA. OLIVER EVANS’S LOCOMOTIVE— 1804. To Oliver Evans belongs the honor of having built and put in operation the first high-pressure steam- engine on record. HAND-BOOK OF THE LOCOMOTIVE. 255 TABLE DEDUCTED FROM EXPERIMENTS ON IRON PLATES FOR STEAM BOILERS, BY THE FRANKLIN INSTITUTE, PHILADA. Iron boiler-plate was found to increase in tenacity as its temperature was raised, until it reached a tem- perature of 550“^ above the freezing-point, at which point its tenacity began to diminish. At 32° to 80° tenacity is 56,000 lbs. or one -seventh be- low its maximum. “ 570° u 66,000 tt the maximum. 11 720° it li 55,000 tt the same nearly as at 30°. a 1050° t( u 32,000 tt nearly one-half the maximum. ti 1240° tt ti 22,000 tt nearly one-third the maximum. t( 1317° tt tt 9,000 tt nearly one -seventh the maximum. It will be seen by the above table that if a boiler should become overheated, by the accumulation of scale on some of its parts or an insufficiency of wa- ter, the iron would soon become reduced to less than one-half its strength. TABLE SHOWING THE RESULT OF EXPERIMENTS MADE ON DIFFERENT BRANDS OF BOILER IRON AT THE STEVENS INSTITUTE OF TECHNOLOGY, HOBOKEN, N. J. Thirty-three experiments were made upon iron taken from the exploded steam-boiler of the ferry- boat Westfield. The following were the results ; 256 HAND-BOOK OF THE LOCOMOTIVE. Lbs. per sq. inch. Average breaking weight .... 41,653 16 experiments made upon high grades of American boiler-plate. Average breaking weight .... 54,123 15 experiments made upon high grades of American flange-iron. Average breaking weight .... 42,144 6 experiments made upon English Bessemer steel. Average breaking weight .... 82,621 5 experiments made upon English Lowmoor boiler-plate. Average breaking weight .... 58,984 6 experiments made upon samples of tank iron from difierent manufacturers. Average breaking weight. No. 1 . . . 43,831 “ No. 2 . . . 42,011 No. 3 . . . 41,249 2 experiments made on iron taken from the exploded steam- boiler of the Bed Jacket. Average breaking weight .... 49,000 It will be noticed that the above experiments re- veal a great variation in the strength of boiler-plate of different grades of iron, and furnish conclusive evidence that the tensile strength of boiler-iron ought to be taken at 60,000 pounds to the square inch instead of 60,000. TABLE SHOWING THE ACTUAL EXTENSION OF WROUGHT-IRON AT VARIOUS TEMPERATURES. Deg. of Fahr. Length. 32° 1. ai2 1.0011356 392 1.0025757 672 1.0043253 752 1.0063894 932 1.0087730 112 1.0114811 1652 1.0216024 2192 1.0348242 2732 1.0512815. 2912 cohesion destroyed. Fusion perfect. Surface becomes straw-colored, deep yellow, crimson, violet, pur- ple, deep blue, bright blue. Surface becomes dull, and then bright red. Bright red, yellow, welding heat, white heat. HAND-BOOK OF THE LOCOMOTIVE. 267 TABIiE SHOWING THZ TENSILE STRENGTH OF VARIOUS QUALITIES OF CAST-IRON. American Cast-Iron, Breaking weight of a square inch bar. Common pig-iron, 15,000 Good common castings, 20,000 Cast-iron 20,834 ‘‘ 19,200 27,700 Gun-heads, specimen from, .... 24,000 “ 39,500 Greenwood cast-iron, 21,300 (after third melting,) . 45,970 Mean of American cast-iron, .... 31,829 Gun-metal, mean, 37,232 English Cast-Iron- Lowmoor, 14,076 Clyde, No. 1, 16,125 Clyde, No. 3, 23,468 Calder, No. 1, . . . . . . . 13,735 Stirling, mean, 25,764 Mean of English, 19,484 Stirling, toughened iron, 28,000 Carron No. 2, cold-blast, 16,683 “ 2, hot-blast, 13,505 3, cold-blast, 13,200 3, hot-blast, 17,755 Davon, No. 3, hot- blast, 21,907 Buffery, No. 1, cold-blast, 17,466 “ 1, hot-blast, 13,437 Cold-Talon (North Wales), No. 2, cold-blast, . 18,855 “ “ 2, hot-blast, . 16.676 22* R 258 HAND-BOOK OF THE LOCOMOTIVE. TABLE SHOWING THE TENSILE STRENGTH OF VARIOUS QUALITIES OF WROUGHT-IRON. American Wrought-Iron, From Salisbury, Conn., . Breaking weight of a square inch bar. . 58,000 ti it it 66,000 Pittsfield, Mass., 57,000 “ Bellefonte, Pa., 58,000 Maramec, Mo., 43,000 it it 53,000 Centre County, Pa., 58,400 ‘‘ Lancaster County, Pa., . 58,061 ‘‘ Carp Eiver, Lake Superior, . 89,582 ‘‘ Mountain, Mo., charcoal bloom. 90,000 American, hammered. 53,900 Chain-iron, 43,000 Eivets, 53,300 Bolts, 52,250 Boiler-plates, 50,000 i( it 60,000 Average boiler-plates. 55,000 joints, double- riveted. 35,700 single ‘‘ • • 28,600 Chrome steel, highest strength. • • 198,910 lowest ‘‘ • • 163,760 ‘‘ average 180,000 English and other Wrought-Irons. Iron, English bar, 56,000 mean of English, . • 53,900 ‘‘ rivets, • . 65,000 Lowmoor iron, .... . . 56,100 HAND-BOOK OF THE LOCOMOTIVE, 259 English and other Wrought-Irons — (Continued). Lowmoor iron plates, Breaking weight of a square inch bar. . . . . 57,881 Bowling plates, • « • • 53,488 Glasgow best boiler. • • • • 56,317 “ ship plates. • • • • 53,870 Yorkshire plates, .* • • • • 57,724 Staffordshire plates, , • • • • 43,821 Derbyshire plates. • • • • 48,563 Bessemer wrought- iron, , • • • • 65,258 a (( « 76,195 tt (( (( 82,110 Russian ‘‘ 59,500 (6 a a 76,084 Swedish 58,084 TABLE SHOWING THE TENSILE STRENGTH OF VARIOUS QUALITIES OP STEEL PLATES. Mersey Co., puddled steel. 108,906 ship-plates, . 99,468 Blochairn puddled steel, . 106,394 boiler-plates, 89,447 Naylor, Vickers & Co., cast. 87,972 C( tc (( u 95,196 T. Turton & Son, • f 95,360 Moss & Gambles, 81,588 Shortridge, Howell & Co., • • 108,900 Homogeneous metal. • • 105,732 “ ‘‘ 2d quality. 81,662 Bessemer steel, .... • • 148,324 tt tt • • • 154,825 tt tt • • • 157,881 260 HAND-BOOK OF THE LOCOMOTIVE. CENTRAL AND MECHANICAL FORCES AND DEFINITIONS. Adhesion. — The measure of the friction between the tires of the driving-wheels and the surface of the rails. Acceleration. — Acceleration is the increase of ve- locity in a moving body caused by the continued action of the motive force. When bodies in motion pass through equal spaces in equal times, or, in other words, when the velocity of the body is the same during the period that the body is in motion, it is termed uniform motion. ^ Angle of Friction. — That pitch of grade at which a loaded car would just stand without descending, being kept at rest by the friction of its bearings. Animal Strength. — As horses were formerly em- ployed for the same purposes that water-wheels, wind- mills, and steam-engines now are, it has become usual to calculate the effect of these machines as equivalent to so many horses; and animal strength becomes thus a sort of measure of mechanical force. Axles. — The railway axle may be considered as having certain relations to a girder in principle. Girders generally have their two ends resting on two points of support, and the load is either located at fixed distances from the props, or dispersed over the whole surface; in the case of the axle the wheels may be considered the props and the journals the loaded parts. HAND-BOOK OF THE LOCOMOTIVE. 261 Attraction. — A tendency which certain bodies have to approach and adhere to each other. There are several kinds of attraction, as of gravitation, co- hesion, capillary, chemical, electrical, etc. Cohesion is that quality of a body which causes its particles to adhere to each other, and to resist being torn apart. Crushing Strength is the resistance which a body opposes to being battered or flattened down by any weight placed, upon it. * Central or Centrifugal Force. — The tendency which bodies in motion have to recede from their centres is called the centrifugal force. Detrusive Strength is the resistance which a body offers to being clipped or shorn into two parts by such instruments as shears or scissors. Force. — Force is the cause of motion or change of motion in material bodies. Every change of mo- tion, viz., every change in the velocity of a body must be regarded as the efiect of a force. On the other hand, rest, or the invariability of the state of motion of a body, must not be attributed to the ab- sence of forces, for equal opposite forces destroy each other and produce no effect. Centripetal Force. — Centripetal force is the force which has a tendency in a moving body to approach the centre of motion or counteract the centrifugal force. Friction is the resistance occasioned to the motion 262 HAND-BOOK OF THE LOCOMOTIVE. of a body when pressed upon the surface of another body which does not partake of its motion. Gravity, or Centre of Gravity. — The forces with which all bodies tend to fall to the earth may be considered parallel : hence, every body may be con- sidered as acted on by a system of parallel forces, whose results may be found ; and these forces, in all posi- tions of the body, act on the same points in the same vertical direction. There is, therefore, in every body a point through which the resultant always passes, in whatever position it is placed. The point is called the centre of gravity of the body. Gyration. — The centre of gyration is that point in which, if all the matter contained in a revolving system were collected, the same angular velocity will be generated in the same time by a given force act- ing at any place as would be generated by the same force acting similarly in the body or system itself. Hydrodynamics. — Hydrodynamics is that branch of general mechanics which treats of the equilibrium and motion of fluids. The terms hydrostatics and hydrodynamics have corresponding signification to the statics and dynamics in the mechanics of solid bodies, viz., hydrostatics is that division of the science which treats of equilibrium of fluids, and hydrody- namics that which relates to their forces and motion. Inertia. — Inertia is that property of matter by which it tends, when at rest to remain so, and when in motion to continue in motion. HAND-BOOK OF THE LOCOMOTIVE. 268 Impetus. — The product of the mass and velocity of a moving body, considered as instantaneous, in distinction from momentum, with reference to time, and force, and also to capacity of continuing its motion. Inclined Plane. — One of the mechanical powers; a plane which forms an angle with the horizon. The force which accelerates the motion of a heavy body on an inclined plane, is to the force of gravity as the sine of the inclination of the plane to the radius, or, as the height of the plane to its length. Indicator. — The very important and useful instru- ment which has contributed so very materially to the perfection and efficiency of our modern steam-engines. Logarithms. — The logarithm of a number is the exponent of a power to which another given invari- able number must be raised in order to produce the first number. Thus in the common system of loga- rithms, in which the invariable number is 10, the loga- rithm of 1000 is 3, because 10 raised to the third power is 1000. Hyperbolic Logarithms. — A system of logarithms, BO called because the numbers expreijs the areas be- tween the asymptote and curve of the hyperbola. Mechanical Power. — Power is a compound of weight multiplied by its velocity; it cannot be in- creased by mechanical means. Power, as the term is only properly used by engi- neers, is the amount of work done in any given 264 HAND-BOOK OF THE LOCOMOTIVE. example in some known time. Its unit is called the horse-power. Momentum, in mechanics, is the same with impetus or quantity of motion, and is generally estimated by the product of the velocity and mass of the body. Motion. — Motion, in mechanics, is a change of place, or it is that affection of matter by which it passes from one point of space to another. Motion is of various kinds, as follows : Absolute motion is the absolute change of place in a moving body independent of any other motion whatever. Accelerated motion is that which is continually receiving constant accessions of velocity. Angular motion is the motion of a body as referred to a centre, about which it revolves. Compound motion is that which is produced by two or more powers acting in different directions. Uniform motion is when the body moves contin- ually with the same velocity, passing over equal spaces in equal times. Natural motion is that which is natural to bodies or that which arises from the action of gravity. Relative motion is the change of relative place in one or more moving bodies. Retarded motion is that which suffers continual diminution of velocity, the laws of which are reverse of those for accelerated motion. Oscillation, or the Centre of Oscillation. — The HAND-BOOK OF THE LOCOMOTIVE. 265 centre of oscillation is that point in a vibrating body into which, if the whole were concentrated and attached to the same axis of motion, it w^ould vibrate in the same time the body does in its natural state. The centre of oscillation is situated in a right line passing through the centre of gravity, and perpen- dicular to the axis of motion. Pendulum. — If any heavy body, suspended by an inflexible rod from a fixed point, be drawn aside from the vertical position, and then let fall, it will descend in the arc of a circle, of which the point of suspension is the centre. Perpetual Motion. — In mechanics, a machine which, when set in motion, would continue to move for- ever, or, at least, until destroyed by the friction of its ^arts, without the aid of any exterior cause. Percussion, or the Centre of Percussion. — The centre of percussion is that point in a body revolving about an axis at which, if it struck an immovable obstacle, all its motion would be destroyed, or it would not incline either way. Prime Movers are those machines from which we obtain power, through their adaptation to the trans- formation of some available natural force into that kind of effort which develops mechanical power. Pneumatics. — The science which treats of the me- chanical properties of elastic fluids, and particularly of atmospheric air. Specific Gravity. — The specific gravity of a body 23 266 HAND-BOOK OF THE LOCOMOTIVE. is the ratio of its weight to an equal volume of some other body assumed as a conventional standard. The standard usually adopted for solids and liquids is rain, or distilled water at a common temperature. Strength is the resistance which a body opposes to disintegration or separation of its parts. Torsion, in mechanics, is the twisting or wrenching of a body by the exertion of a lateral force. Torsional strength is the resistance which a body offers to any external force which attempts to twist it. Transverse strength is the resistance to bending or flexure. Velocity, or Virtual Velocity. — Virtual velocity, in mecli allies, is the velocity which a body in equilibrium would actually acquire during the first instant of it% motion, in case of the equilibrium being disturbed. Vi^eights and Measures. — The weights and meas- ures of this country are identical with those of Eng- land. In both countries they repose in fact upon actually existing masses of metal (brass), which have been individually declared by law to be the units of the system. Work. — Work is force acting through space, and is measured by multiplying the measure of the force by the measure of the space. HAND-BOOK OF THE LOCOMOTIVE. 257 TABLE (CONTAINING DIAMETERS, CIRCUMFERENCES, AND AREAS OP CIRCLES FROM OF AN INCH TO 10 INCHES, ADVANCING BY OF AN INCH; AND BY | OF AN INCH FROM 10 INCHES TO 50 INCHES DIAMETER. DIAM. CIRCUM. AREA. DIAM. CIRCUM. AREA. Inch. Inches. Inches. Inch. Inches. Inches. 1 TB’ .1963 .0030 1 5 6.0868 2.9483 T .3927 .0122 2 6.2832 3.1416 A .6890 .0276 A 6.4795 3.3411 i .7854 .0490 i 6.6759 3.5465 A .9817 .0767 A" 6.8722 3.7582 f 1.1781 .1104 1 X 7.0686 3.9760 tV 1.3744 .1503 A 7.2640 4.2001 1.5708 .1963 f 7.4613 4.4302 A 1.7671 .2485 A 7.6576 4.6664 i 1.9635 .3068 i 7.8540 4.9087 ii 2.1598 .3712 A 8.0503 5.1573 i 2.3562 .4417 5. 8.2467 5.4119 if 2.5525 .5185 H 8.4430 5.6727 2.7489 .6013 f 8.6394 5.9395 1 5 TB" 2.9452 .6903 H 8.8357 6.2126 1 3.1416 .7854 1 9.0321 6.4918 A 3.3379 .8861 ii 9.2284 6.7772 1 s 3.5343 .9940 3 9.4248 7.0686 A 3.7306 1.1075 A 9.6211 7.3662 i 3.9270 1.2271 i 9.8175 7.6699 A 4.1233 1.3529 A 10.0138 7.9798 1 4.3197 1.4848 i 10.2120 8.2957 A 4.5160 1.6229 tV 10.4065 8.6179 i 4.7124 1.7671 1 10.6029 8.9462 A 4.9087 1.9175 A 10.7992 9.2806 f 5.1051 2.0739 i 10.9956 9.6211 ii 5.3014 2.2365 A 11.1919 9.9678 f 5.4978 2.4052 1 11.3883 10.3206 il 5.6941 2.5801 H 11.5846 10.6796 i 5.8905 2.7611 i 11.7810 11.0446 268 HAND-BOOK OF THE LOCOMOTIVE. table — {Continued) CONTAINING DIAMETERS, CIRCUMFERENCES, ETC. DIAM. CIRCUM. AREA. DIAM. CIRCUM. AREA. Inch. Inches. Inches. Inch. Inches. Inches. a 11.9773 11.4159 . 18.6532 27.6884 i 12.1737 11.7932 « 18.8496 28.2744 a 12.3700 12.1768 A 19.0459 28.8665 4 12.5664 12.5664 i 19.2423 29.4647 tV 12.7627 12.9622 A 19.4386 30.0798 12.9591 13.3640 k 19.6350 30.6796 A 13.1554 13.7721 A 19.8313 31.2964 13.3518 14.1862 f 20.0277 31.9192 A 13.5481 14.6066 A 20.2240 32.5481 f 13.7445 15.0331 i 20.4204 83.1831 A 13.9408 15.4657 A 20.6167 33.8244 i 14.1372 15.9043 i 20.8131 34.4717 14.3335 16.3492 H 21.0094 35.1252 1 14.5299 16.8001 i 21.2058 35.7848 H 14.7262 17.2573 ii 21.4021 36.4505 i 14.9226 17.7205 i 21.5985 37.1224 if 15.1189 18.1900 H 21.7948 37.8005 i 15.3153 18.6655 7 21.9912 38.4846 if 15.5716 19.1472 A 22.1875 39.1749 Y 15.7080 19.6350 22.3839 39.8713 tV 15.9043 20.1290 A 22.5802 40.5469 i 16.1007 20.6290 i 22.7766 41.2825 16.2970 21.1252 A 22.9729 41.9974 i 16.4934 21.6475 1 23.1693 42.7184 16.6897 22.1661 A 23.3656 43.4455 1 16.8861 22.6907 Y 23.5620 44.1787 tV 17.0824 23.2215 A 23.7583 44.9181 i 17.2788 23.7583 i 23.9547 45.6636 17.4751 24.3014 24.1510 46.4153 '• f 17.6715 24.8504 i 24.3474 47.1730 • if 17.8678 25.4058 A 24.5437 47.9370 1 18.0642 25.9672 i 24.7401 48.7070 if 18.2605 26.5348 11 24.9364 49.4833 1 18.4569 27.1085 8 25.1328 50.2656 HAND-BOOK OF THE LOCOMOTIVE. 269 T A B Li E — CONTAINING DIAMETERS, CIRCUMFERENCES, ETC. DIAM. CIRCUM. AREA. DIAM. CIRCUM. AREA. Inch. Inches. Inches. Inch. Inches. Inches. A 25.3291 51.0541 f 32.5941 84.5409 i 25.5265 51.8486 i 32.9868 86.5903 25.7218 52.8994 i 33.3795 88.6643 1 x 25.9182 53.4562 1 33.7722 90.7627 A 26.1145 54.2748 i 34.1649 92.8858 1 26.3109 55.0885 11 34.5576 95.0334 tV 26.5072 55.9138 34.9503 97.2053 i 26.7036 56.7451 i 35.3430 99.4021 A 26.8999 57.5887 i 35.7357 101.6234 27.0963 58.4264 i 36.1284 103.8691 TF 27.2926 59.7762 f 36.5211 106.1394 V X 27.4890 60.1321 i 36.9138 108.4342 H 27-6853 60.9943 i 37.3065 110.7536 27.8817 61.8625 12 37.6992 113.0976 TF 28.0780 62.7369 i 38.0919 115.4660 9 28.2744 63.6174 i 38.4846 117.8590 A 28.4707 64.5041 I 38.8773 120.2766 i 28.6671 65.3968 i 39.2700 122.7187 tV 28.8634 66.2957 1 39.6627 125.1854 i 29.0598 67.2007 i 40.0554 127.6765 29.2561 68.1120 40.4481 130.1923 3. 29.4525 69.0293 13 40.8408 132.7326 tV 29.6488 69.9528 41.2338 135.2974 i 29.8452 70:8823 i 41.6262 137.8867 A 30.0415 71.8181 1 42.0189 140.5007 5 ■5“ 30.2379 72.7599 i 42.4116 143.1391 ii 30.4342 73.7079 1 42.8043 145.8021 f 30.6306 74.6620 f 43.1970 148.4896 il 30.8269 75.6223 43.5897 151.2017 ? 31.0233 76.5887 14 43.9824 153.9384 ft 31.2196 77.5613 i 44.3751 156.6995 10 31.4160 78.5400 i 44.7676 159.4852 i 31.8087 80.5157 I 45.1605 162.2956 1 32.2014 82.5160 i 45.5532 165.1303 23 * 270 HAND-BOOK OF THE LOCOMOTIVE. T A 13 Li E — {Continued) CONTAINING DIAMETERS, CIRCUMFERENCES, ETC. DIAM. CIRCUM. AREA. DIAM. CIRCUM. AREA. Inch. Inches. Inches. Inch. Inches. Inches. 1 45.9459 167.9896 59.2977 279.8110 1 46.3386 170.8735 19 59.6904 283.5294 i 46.7313 173.7820 i 60.0831 287.2723 15 47.1240 176.7150 i 60.4758 291.0397 i 47.5167 179.6725 1 60.8685 294.8312 i 47.9094 182.6545 i 61.2612 298.6483 f 48.3021 185.6612 1 61.6539 302.4894 h 48.6948 188.6923 I 62.0466 306.3550 1 49.0875 191.7480 1- 62.4393 310.2452 i 49.4802 194.8282 20 62.8320 314.1600 i 49.8729 197.9330 i 63.2247 318.0992 16 50.2656 201.0624 i 63.6174 322.0630 50.6583 204.2162 i 64.0101 326.0514 i 51.0510 207.3946 i 64.4028 330.0643 i 51.4437 210.5976 1 64.7955 334.1018 51.8364 213.8251 I 65.1882 338.1637 52.2291 217.0772 •g- 65.5809 342.2503 s. 4 52.6218 220.3537 21 65.9736 346.3614 i 53.0145 223.6549 i 66.3663 350.4970 17 53.4072 226.9806 i 66.7590 354.6571 i 53.7999 230.3308 ■| 67.1517 358.8419 i 54.1926 233.7055 i 67.5444 363.0511 1 54.5853 237.1049 1 67.9371 367.2849 54.9780 240.5287 3. 4 68.3298 371.5432 1 55.3707 243.9771 F 68.7225 375.8261 f 55.7634 247.4500 22 69.1152 380.1336 i 56.1561 250.9475 4 69.5079 384.4665 18 56.5488 254.4696 i 69.9006 388.8220 56.9415 258.0161 1 70.2933 393.2031 i • 57.3342 261.5872 i 70.6860 397.6087 •1 57.7269 265.1829 i 71.0787 402.0388 1 58.1196 268.8031 3. 4 71.4714 406.4935 1 58.5123 272.4479 4 71.8641 410.9728 i 58.9056 276.1171 23 72.2568 415.4766 HAND-BOOK OF THE LOCOMOTIVE. 271 T A 13 Tj E — {(Continued) CONTAINING DIAMETERS, CIRCUMFERENCES, ETC. DIAM. CIRCUM. AREA. DIAM. CIRCUM. : AREA. Inch. Inches. Inches. Inch. Inches. Inches. 72.6495 420.0049 i 78.9327 495.7950 \ 73.0422 424.5577 i 79.3254 500.7415 1 73.4349 429.1352 79.7181 505.7117 73.8276 433.7371 80.1108 510.7063 1 74.2203 438.3636 1 80.5035 515.7255 f 74.6130 443.0146 i 80.8962 520.7692 1 75.0057 447.6992 •g- 81.2889 525.8375 24 75.3984 452.3904 26 81.6816 530.9304 i 75.7911 457.1150 i 82.0743 536.0477 i 76.1838 461.8642 i 82.4670 541.1896 f 76.5765 466.6380 1 82.8597 546.3561 76.9692 471.4363 83.2524 551.5471 1 77.3619 476.2592 I 83.6451 556.7627 i 77.7546 •481.1065 1 84.0378 562.0027 i 78.1473 485.9785 •g- 84.4305 567.2674 25 78.5400 490.8750 To find the circumferences of larger circles, multi- ply the diameter by 3.1416. For areas of larger circles, multiply the square of the diameter by .7854. To find the diameter of any circle, divide the cir- cumference by 3.1416. To find the diameter when the area is given, divide the area by the decimal .7854, and extract the square root of the quotient ; that will give the diameter. 272 HAND-BOOK OF THE LOCOMOTIVE. INCRUSTATION IN STEAM-BOILERS. All waters contain more or less mineral matter, which is acquired by percolation through the earth’s surface, and consists principally of carbonate of lime and magnesia, sulphate of lime and chloride of sodium in solution, clay, sand, and vegetable matter in suspension. Some waters contain far less mineral ingredients than others — such as rain-water, the water of lakes and large rivers, whilst wells, springs, and creeks hold large quantities in solution. When such water is boiled, the carbonic acid is driven off, and the carbonates, deprived of their sol- vents, are rapidly precipitated in a finely crystallized form, tenaciously adhering to the surface of the iron. Chloride of sodium, and all such soluble salts, are precipitated in the same way by supersaturation. This combined deposit, of which carbonate of lime forms the greater part, remains adherent to the inner surface of the boiler, undisturbed by the force of the most violent boiling currents. Gradually this accumulation becomes harder and thicker, until it is as dense as porcelain, thereby preventing the proper heating of the water by any fire that can be placed in the furnace. The high temperature necessary to heat water through thick scale will sometimes convert the scale into a sub- stance resembling glass. HAND-BOOK OF THE LOCOMOTIVE. 273 The evil effect of scale in steam-boilers is due to the fact that it is a non-conductor of heat. The con- ducting power of scale compared with that of iron is as 1 to 37 ; consequently a greater amount of fuel is required to heat water in an incrusted boiler than if the same boiler were clean. Scale of an inch thick will require an expendi- ture of fifteen per cent, more fuel. This expenditure increases as the scale becomes thicker ; thus, when it is a quarter of an inch thick, sixty per cent, more fuel is needed to raise water in a boiler to any given heat. If the boiler is badly scaled, the fire-surface of the boiler must be heated to a temperature accord- ing to the thickness of the scale. For example : To raise steam to a pressure of 90 pounds, the water must be heated to a temperature of 324° Fah. If a quarter of an inch of scale inter- venes between the shell and the water, it would be necessary to heat the fire-surface of the boiler nearly 600°, or 100° Fah. above the maximum strength of iron. Now, it is a well-known fact that the higher the temperature at which iron is kept, the more rapidly it oxidizes, and is made liable at any time to bulge or crack by internal pressure, and is often the cause of explosions. At a meeting of the Railway Mechanics’ Associa- tion, held at Louisville, Kentucky, in 1871, the com- mittee to whom was referred the subject of boiler incrustations reported that they had prepared and S 274 HAND-BOOK OF THE LOCOMOTIVE. issued, through the secretary of the association, a cir- cular of questions to all the master mechanics of various railroads throughout the country, in order to elicit such informationi as they might possess on this subject. In compliance therewith, communications had been received from over sixty master mechanics, and the information so obtained was very extensive and val- uable, confirming in substance the theory advanced in a paper read in the convention last year, to the *efiect that the only effectual way to prevent incrustation is to purify the water, if possible, before it is allowed to enter the boiler. To this end the committee directed its efforts, and had given special attention to the reports of those who have experimented, with a view thereby of ascertaining the best and cheapest mode of accom- plishing the same. From all communications re- ceived, it is found that most of the roads located in the Eastern and Southern States are troubled but little with incrustation, while those in Middle States are variously affected — some suffering greatly, others none at all. Western roads suffer most, many of them finding it necessary, in order to maintain average economy in fuel and reasonable safety to the boiler, to take out flues once in six to twelve months, for the pur- pose of removing scale from both boiler and tubes. Railway engineers in Western States realize eimilar HAND-BOOK OF THE LOCOMOTIVE. 275 difficulties in a greater or less degree, according to location. Mr. Ham, of the New York Central, stated that he can run with economy on the Eastern Division four years without taking out the flues; while on the Middle Division, on account of lime and scale, he has to take them out, on an average, every year and a half) and on the Western Division every two years. He finds it necessary, on the Middle Divi' sion, to put new sheets in the bottom of the cylinder part of the boiler on an average every five years ; and with good water has only repaired that portion of the boiler once in eight to ten years. He knows nothing equal to pure water to keep boilers free from mud and scale. At another meeting of the American Railway Master Mechanics’ Association, the committee to whom was referred the subject of steam-boiler incrus- tation, after a series of very exhaustive experiments, reported that the only preventive against incrusta- tion was the use of pure water in steam-boilers. It was also stated that the extra expense in one year, from impure water and incrustation, would amount to S75,000 for every hundred locomotives. The committee considered that to boil sufficient water to supply a locomotive for one year, running 81,000 miles, would require an extra expenditure of $236 for fuel ; but they considered that that was the only reliable means for preventing incrustation and all manner of ruptures and leaks in boilers. 276 HAND-BOOK OF THE LOCOMOTIVE. As before stated, what is needed to render efficient and permanent relief is an article that will attack the scale, render it porous, and destroy the affinity between it and the iron, without any injuries to the latter, and will hold the minerals and ingredients, which are passing in with the feed-water, in the form of slush or sludge, until they can be blown out. G. W. Lord, a practical manufacturing , chemist of Philadelphia, wh® has been, at various times, con- nected with many mechanical enterprises in this country, the West Indies, and South America, has succeeded, by experiment and observation, in pro- ducing an article — Lord’s patent boiler compound — which has been in use over eight years in all parts of the United States, Canada, South America, Mexico, and Cuba, under the most varying circum- stances, and in all cases with satisfactory results. The manufacturer and patentee can produce more than ten thousand testimonials of its efficiency from engineers and steam-users. It neutralizes mine and mineral waters, which contain lime, iron, sulphur, and carbonates, destroys their affinity, and renders them simple and harmless. It not only prevents the formation of new scale, but decomposes the old and converts it into a soluble sediment, which may be blown out every day. It contains no acid which has any injurious effect on the iron of the boiler, — evidence of which may be found in the fact that the manufacturer, some years ago, filled several thousand vials with a solution of his compound, in which was placed a quantity of bright iron turn- HAND-BOOK OF THE LOCOMOTIVE. 277 ings and small pieces of steel wire, which appear as bright as the day they were immersed in the solu- tion, one of which will be sent to any one who feels incredulous on the subject. Lord’s compound gives relief in all cases when used according to directions. Parties wishing to test its efficiency should address Geo. W. Lord, Philadelphia, Pa. GEO. STEPHENSON’S LOCOMOTIVE, THE " ROCK ET " — 1829. The above cut represents George Stephenson’s loco- motive “ The Rocket,” which won the prize at Man- chester, 1829, and fully established the success of the locomotive. 24 278 HAND-BOOK OF THE LOCOMOTIVE, BOILER EXPLOSIONS. The risk of life and property involved in the use of the steam-boiler is still, as it has always been, a source of constant anxiety to the engineer and steam user. Explosions continually take place, under cir- cumstances of the utmost apparent security. Occur- ring without warning, and occupying but an instant of time, it is generally difficult, if not impossible, except in rare instances, to ascertain with certainty their true cause. There is seldom a unanimous opinion on the part of experts who examine into the causes after the event. But experience in the care and management of steam-boilers has fully demonstrated that the prin- cipal causes that tend to produce explosions are — deficiency of strength in the shell or other parts of a boiler, insufficient bracing, unequal expansion, faulty construction, leakage, oxidation or rusting away of the iron, internal grooving, over-pressure, excessive firing, ignorance, recklessness, and mismanagement. The above includes everything that an intelligent experience has shown us would cause a steam-boiler to explode, and it will be seen that the remedy is within the control of practical and intelligent men. Of course boilers sometimes give out in places least expected, and show weaknesses, that have been de- veloped by use, that perhaps could not have been discovered in any other way ; and there may also be HA2sD-BOOK OF THE LOCOMOTIVE, 279 280 HAND-BOOK OF THE LOCOMOTIVE. iLstances where no satisfactory reason can be assigned, but it is possible that even these could be accounted for, were all the circumstances known. Though we are indebted to science for ideas and facts that have solved some of the most knotty problems in mechanics, still scientific men seem to be more in the dark on the subject of steam-boiler explosions than most of our experienced practical men engaged in the care or running of boilers, as their theories do not accord with facts that are+)rought to light in every-day practice. It is well enough in some cases to advance theories, no matter how absurd they may be, because they induce thought, comment, and experiment, by which at least something may be gained; but the evils likely to arise from theories advanced in the case of boiler explosions are that these scientific theories are apt to be accepted as an established fact before anything has been proved, because they are given to the public on occasions when every one is excited by, and anxious to learn the cause of, some terrible disaster. The investigation of the causes which led to the explosion of the ferry-boat Westfield covered a great deal of paper, but its practical meaning might be con- densed into a small space, as the investigation re- vealed the fact that the shell of that boiler concealed for years nearly every defect that leads directly and indirectly to disaster. On that, as well as on all former occasions of a like character, the scientific ex- HAND-BOOK OF THE LOCOMOTIVE. 281 perts were on hand with the gas, electricity, decom- posed steam, dissociation of water, concussive ebulli- tion, and fatigue of metal theories. The fact that the engineer in charge did not know whether the steam- gauge and safety-valves on his boiler were in a ser- viceable condition or not ; or that, according to Fair- bairif s experiments, and. all past and present expe- rience in the strength of steam-boilers, he was carry- ing about twice the pressure that the boiler would stand \Vith safety when new, did not seem worthy of the attention of the scientific experts. Of course it would be unscientific to attribute the cause of such a disaster to imperfections in construction, poor workmanship, scant bracing, cracked flanges, etc. It is true we have commissioners appointed by the Government for the purpose of making experiments, and finding out, if possible, why boilers explode, but the results of such experiments never amount to anything, nor is any one better posted on boiler ex- plosions after the experiment is over. The idea of building a steam-boiler and then bursting it for the purpose of showing how much strain it took to burst it, seems to be akin to knocking a man^s brains out with a club for the purpose of showing the jury on the trial of a murder case how hard a blow it must have taken to kill the murdered man. Experiments on obsolete or especial types of boilers, or those made in the laboratory, will do little towards preventing the explosion of boilers, because the conditions under 24 * 282 HAND-BOOK OF THE LOCOMOTIVE. which boilers are used in manufactories are very dif- ferent from those under which experimental boilers are used. Test of safety-valves and steam-gauges would be beneficial, as it would undoubtedly reveal a great many defects in their construction, and would have a tendency to direct the attention of steam users and inventors to the improvement of these most indispensable adjuncts of the steam-boiler. All practical experience in the construction, care, and management of steam-boilers goes to show that there is hardly any two boilers alike, owing to defects in the material, design, construction, bracing, etc., so that the bursting of 100 boilers would not establish any criterion for the strength and durability of boilers in general. Prudent steam users are not so anxious to find out what would burst a boiler as they are to know what would not burst it ; because the record of boiler explosions in the past goes to show that it does not need any scientific training to enable men to burst or blow up a boiler, for men who just learn enough to put coal into a furnace and look at an engine run, often furnish very convincing proof that they are fully competent to do that. The question will very naturally be asked : “ How shall boiler explosions be rendered less frequent, or })revented altogether ? ” And the answer is that no specific rule can be laid down that will apply to all boilers ; each case requires treatment in accordance with the circumstances connected with it, — that is, HAND-BOOK OF THE LOCOMOTIVE. 283 the type of boiler, pressure carried, character of bracing, quality of water, efficiency of attendant, etc. Experience has taught us, so far, that the ma- jority of explosions that have taken place has been caused by circumstances which might have been pre- vented, had sufficient care been exercised in the selec- tion of materials for the boiler in the process of con- struction, and in the care of the boiler after it was put under steam. Information of great value can be obtained on the most practical means of preventing steam-boiler ex- plosions from the yearly reports of the Hartford Steam-Boiler .Inspection and Insurance Company. These reports show, conclusively, that a thorough and searching examination of steam-boilers by com- petent men is the only means of discovering defects which must eventually produce explosions, and in proof of which might be cited the fact that wherever steam-boilers have been subjected to the inspection of that Company, the community received complete immunity from steam-boiler explosions. Take, for instance, the city of Philadelphia, where the inspec- tion of that Company comprises about 2,000 steam- boilers, — not one explosion has occurred within the past five yearf, though prior to that time they were of frequent occurrence. What is true of Philadelphia is true of other places. But it is the locomotive boiler that we have more directly to deal with now. The inspection and 284 HAND-BOOK OF THE LOCOMOTIVE. examination of that class of boilers is more difficult than that of any other, as they are of necessity com- plicated and difficult to enter ; but, nevertheless, the American Master Mechanics’ Association, a body of very talented and practical mechanics, have taken the subject of boiler explosions in hand at their yearly convention, and as they show by their discus- sions that they are no visionary theorists, but men of sound practical ideas, there cannot be any doubt but that their deliberations will elicit such information as will cause locomotive boiler explosions to be less frequent than they have been in the past. And as an evidence that they* are fully alive to the best means for preventing such disasters, the more practical of them, at their last convention, declared that the first step to be taken to prevent boiler explosions is to secure good material for the boiler; next, good work- manship, and then care and intelligence in their use and management. The number of locomotive boilers that exploded in the United States within the last six years amounted to 103, causing the loss of 151 lives, and property to the amount of several million dollars. Any class of men that, by their practical intelligence and example, will render such disasters less frequent^ will confer a great boon on mankind. HAND-BOOK OF THE LOCOMOTIVE. 285 ACCIDENTS. Rules for the Course to be followed by the Bystanders in case of Injury by Machinery, where Surgical As- sistance cannot at once be obtained. If there is bleeding, do not try to stop it by bind- ing up the wound. The current of the blood to the part must be checked. To do this, find the artery by its beating; lay a firm and even compress or pad (made of cloth or rags rolled up, or a round stone Fig. 1. Fig. 2. Fig. 3. or a piece of wood well wrapped) over the artery, (see Fig. 1 ;) tie a handkerchief around the limb and compress ; put a stick through the handkerchief and twist the latter up till it is just tight enough to stop the bleeding; then put one end of the stick under the handkerchief to prevent untwisting, as in Fig. 3. The artery in the thigh runs along the inner side of the muscle in front, near the bone. A little above the knee it passes to the back of the bone. In inju- ries at or above the knee, apply the compress high up on the inner side of the thigh, at the point where 28G HAND-BOOK OF THE LOCOMOTIVE. the two thumbs meet at C, in Fig, 4, with the knot on the outer side of tlie thigh. When the leg is injured below the knee, apply the compress at the back of the thigh, just above the knee, at C, in Fig, 2, and the knot in front, as in Figs. 1 and 3. The artery in the arm runs down the inner side of the large muscle in front, quite close to the bone. Lower down it gets farther forward toward the bend of the elbow. It is most easily found and compressed a little above the middle. (See Fig. 5.) Fig. 4. Care should be taken to examine the limb from time to time, and to lessen the compression if it becomes very cold or purple ; tighten up the hand- kerchief again if the bleeding begins afresh. In the case of shock, when the injured person lies pale, faint, cold, and sometimes insensible, with labored pulse and breathing, anything like excite- ment must be avoided, as it tends to exhaust the patient, who should be laid down with the head rather low. Much talking should be strictly avoided. HAND-BOOK OF THE LOCOI^OTIVE. 287 - unless in words of encouragement. External warmth should be applied, and the person covered with blankets, and bottles of hot water or hot bricks ap- plied to the feet and to the armpits. Burns and Scalds. — Injuries of this kind are more dangerous when situated on the chest or body than when on the limbs. Burns are generally more severe than scalds, because the skin is more fre- quently destroyed, producing a slough or mortifica- tion of the part, which must separate and come away before the wound can be healed. Scalds from hot water or steam are usually less severe, unless very extensive, as the scarf skin is only raised like a common blister ; but should the injury from* either scalds or burns be severe, a shivering, followed by depression, is very likely to come on. To check this, some warm wine and water, or spirits and water, should be given without delay, and bottles of hot water applied to the hands and feet to support warmth. Bruises. — Wounds arising from heavy bodies fall- ing on the person, or the person falling from a con- siderable height, require prompt treatment; but dan- ger generally arises from the shock to the system, and until the arrival of medical aid all efforts should be directed to making the patient as comfort- able as possible, by warm applications or poultices. Flannel made warm and applied to the skin, and in some cases cold water, is very refreshing. Stimulants 288 HAND-BOOK OF THE LOCOMOTIVE. should be avoided except in cases demanding their administration, but they are agents of great value in the treatment of that condition of collapse and faint- ness which very commonly occurs after severe injury. In administering stimulants, the best practical rule is to give a small quantity at first and watch the effect ; if the surface becomes warmer, the breathing deeper and more regular, and the pulse at the wrist more perceptible, then there can be no question as to the advantage of giving a little mgre. The first locomotive built in the United States that bore any resemblance to the modern locomotive. Diam. of cylinders, 5i inches ; stroke, 16 in. ; diam. of drivers, 4i feet. The boiler contains 32 copper tubes, 4 inches in diameter and 5 feet long. Weight of locomotive complete, 4 tons. HAND-BOOK OF THE LOCOMOTIVE. 289 TABLE SHOWING THE TIME AT 80 DIFFERENT PEACES, WHEN TI IS 12 o’clock at new YORK CITY; ALSO, COLUMN SHOWING DIFFERENCE OF TIME FROM NEW YORK. New York City, 12 M. Fast. Slow. Places. H. M. S. H 31. S. H. M s. Albany, N. Y 12 1 1 P. M. 1 1 Annapolis, Md 11 50 4 A. M. *9 5*^ Augusta, Me 12 16 40 P. M. 16 46 ... Baltimore, Md 11 49 33 A. M. 16 27 Bangor, Me 12 20 52 P. M. 20 52 Boston, Mass 12 11 46 P. M. 11 46 Bufialo', N. Y 11 40 20 A. M. 1*9 4*0 Cambridge, Mass 12 11 30 P. M. li 30 Charleston, S. C 11 36 18 A. M. 23 4*2 Chicago, 111 11 5 29 A. M. 54 31 Cincinnati, 0 11 18 2 A. M. 41 58 Cleveland, 0 11 23 36 A. M. 31 24 Clinton, N. Y 11 54 23 A. M. 5 37 Columbus, 0 11 23 48 A. M. 36 12 Concord, N. H 12 10 4 P. M. 10 *4 ... Detroit, Mich 11 23 50 A. M. 3*6 10 Dover, N. H 12 12 24 P. 31. 12 24 ... Eastport, Me 12 23 16 P. M. 28 10 ... Fall River, Mass 12 11 32 P. M. 11 32 ... Frankfort, Ky 11 17 20 A.M. 42 4*6 Gloucester, Mass 12 13 21 P. M. 1*3 21 ... Greenwich, Eng 4 56 P. 31. 4 56 ... Halifax, N. S 12 41 33 P. M. 41 33 ... Hallowell, Me 12 16 40 P. 31. 16 40 Harrisburg, Pa 11 48 40 A. M. 1 *1* 2*6 Hartford, Conn 12 5 17 P. M. 5 1*7 Havana, Cuba 11 26 29 A. M. 3*3 31 Key West, Fla 11 28 50 A. M. ... 31 10 Leavenworth, Kan.... 10 37 14 A. M. ... *’i 22 56 Lexington, Ky 11 18 48 A. M. 41 12 Liverpool, Eng 4 43 59 P. M. 4 43 59 ... ... 26 T 290 HAND-BOOK OF THE LOCOMOTIVE. T A B I-i '^ — {Continued) SHOWING THE DIFFERENCE OF TIME, ETC. New York City, 12 M. Fast. Slow. Places. H. M. s. H. M. S. H. M. s. Lockport, N. Y 11 40 56 A. M. 19 4 London, Eng 4 55 36 P. M. *4 55 36 ... Louisville, Ky 11 14 ... A. M. 4*6 Lowell, Mass 12 10 44 r. M. io 44 ... Memphis, Tenn 10 55 28 A. M. 1 *4 32 Milwaukee, Wis. 11 4 23 A. M. ... 55 37 Mobile, Ala 11 3 54 A. M. 66 6 Montpelier, Vt 12 5 36 P. M. ... ’5 36 Montreal, C. E 12 1 48 P. M. 1 48 Nantucket, Mass 12 15 38 P. M. 15 38 Newark, N. J 11 59 20 A. M. ... 4*6 New Bedford, Mass... 12 12 18 P. M. 12 18 Newbury port. Mass... 12 12 32 P. M. ... 12 32 New Haven, Conn 12 4 18 P. M. 4 18 ... New London, Conn... 12 7 40 P. M. 7 40 ... New Orleans, La 10 56 A.M. ... 1 *4 ... Newport, E. I 12 10 46 P. M. 10 46 Niagara Falls, N. Y. . 11 39 44 A. M. ... 2*6 16 Norfolk, Va 11 50 46 A. M. ... 9 14 Northampton, Mass... 12 5 30 P. M. 5 3*6 Omaha City, Neb 10 32 4 A. M. *1 2*7 56 Oswego, N. Y 11 49 36 A. M. 10 24 Paris, France 5 5 21 P. M. *5 ”5 2*1 ... ... Philadelphia, Pa 11 55 20 A. M. ... ... 4 26 Pikers Peak, Col 9 56 ... A. M. ... ... 2 4 ... Pittsburg, Pa 11 35 52 A. M. ... 24 8 Portland, Me 12 15 2 P. M. 1*5 2 ... Portsmouth, N. H 12 12 57 P. M. 12 57 ... ... Providence, E. I 12 10 25 P. M. ... 10 25 Provincetown, Mass... 12 15 48 P. M. 15 48 ... ... Quebec, C. E 12 11 11 P. M. 11 11 ... Ealeigh, N. C 11 40 48 A. M. ... 19 12 Eichmond, Va .... 11 46 10 A. M. ... ... ... 13 50 Eochester, N. Y 11 44 36 A.M. ... ... ... 15 24 Sacramento City, Cal. 8 50 9 A.M. ... ... *3 9 51 HAND-BOOK 01 THE LOCOMOTIVE. 291 TABLE — {Continued) SHOWING THE DIFFERENCE OF TIME, ETC. New York City, 12 M. Fast. Slow. Places. H. M. s. H. M. s. H. M. S. Salem, Mass 12 12 26 P. M. 12 26 Salt Lake City, Utah. 9 27 36 A. M. ... ”2 32 24 San Francisco, Cal.... 8 46 13 A. M. 3 13 47 Saratoga, N. Y 12 1 P. M. 1 ... Savannah, Ga 11 31 39 A. M. ... 28 21 Springfield, Mass 12 5 37 P. M. *5 37 ... St. Louis, Mo 10 54 59 A. M. ... 1 *i Syracuse, N. Y 11 51 12 A. M. ... 48 Tallahassee, Fla 11 17 36 A. M. 42 24 Toronto, C. W 11 38 27 A. M. ... 21 33 Trenton, N. J 11 37 24 A. M. 2 36 Utica, N. Y 11 55 8 A. M. ... 4 52 Washington, I). C 11 47 48 A. M. 12 12 West Point, N. Y 12 10 P. M. « M. W. BALDWIN’S LOCOMOTIVE “ I RONSi DES ” — 1832. The above locomotive was placed on the Philadel- phia, Germantown & Norristown E.E., and estab- lished the success of the locomotive in the U. S. 292 HAND-BOOK OF THE LOCOMOTIVE. DISTANCE BY RAILROAD BETWEEN IMPOR- TANT PLACES IN THE UNITED STATES. MILES. From New York to Albany 144 Baltimore, Md 184 Boston 236 Buffalo, via Hornellsville 423 Buffalo, via Albany 442 Charleston, S. C 788 Chicago, via Albany, Buffalo and Cleveland.. 980 Chicago, via Buffalo and Cleveland 1043 Chicago, via Erie Rail- way and Cleveland 957 Chicago, via Philadelphia and Pittsburg 935 Cincinnati, v i a Albany and Buffalo 880 Cincinnati, via Erie Rail- way and Dunkirk 857 Cincinnati, via Philadel- phia and Pittsburg 807 Cleveland, via Albany and New York Central 625 Cleveland, via Erie Rail- way 602 Cleveland, via Philadel- phia and Pennsylvania 580 Dunkirk 460 Indianapolis, via Albany, Buffalo and Cleveland.. 911 Indianapolis, via Erie Railway and Cleveland 888 MILES. From New York to Indianapolis, via Phila- delphia and Pittsburg.. 838 Louisville, via Dunkirk... 994 Louisville, via Philadel- phia 946 Milwaukee, Wis.,via Dun- kirk and Chicago 1049 Mobile, Ala 1432 Montreal, Canada 403 Niagara Falls, via Erie Railway 438 Niagara Falls, via New York Central 447 Philadelphia 87 Quebec, Canada 582 Richmond, Va 355 Rock Island, 111 1139 St. Louis, via Dunkirk and Chicago 1242 Washington, D. C 244 From Boston to Albany 200 Augusta, Me 165 Baltimore 420 Bumdo 418 Charleston, S. C 1018 Chicago, via Canada 1013 Cincinnati, via Cleveland 936 Halifax, N. S 653 Montreal, Canada 322 HAND-BOOK OF THE LOCOMOTIVE. 293 From Boston to New Orleans, La 1828 New York, via Hartford.. 236 Philadelphia 323 Portland, Me 105 Quebec, Canada.. 422 Kichmond, Va 591 Savannah, Ga 1143 St. Louis, via Chicago 1298 Washington, D. C 460 From Philadelphia to Baltimore 97 Boston 323 Buffalo 424 Charleston 789 Chicago 847 Cincinnati, via Pittsburg and Steubenville 663 Cleveland, via Pittsburg . 492 Detroit, Mich 766 Elmira 275 Galena, 111 1018 Harrisburg, Pa 106 Indianapolis, via Steuben- ville and Columbus 730 Louisville, via Steuben- ville and Cincinnati 796 Louisville, via Pittsburg and Ohio River- 963 Milwaukee, via Cleveland 937 Mobile 1345 Montgomery, Ala 1148 New Orleans 1511 Niagara Falls 443 Pittsburg 353 25 * MILES From Philadelphia to Pottsville, Pa 93 Richmond, Va 268 Rochester, N. Y 373 Rock Island, via Chicago 1028 Savannah, Ga 901 St. Louis, via Cleveland and Chicago 1132 St. Louis, via Pittsburg and Indianapolis 1022 St. Louis, via Pittsburg and Cincinnati. 1050 Toronto, via Catawissa and Niagara 497 Washington, D. C 137 From Baltimore to Boston 420 Charleston, S. C 692 Chicago, via Wheeling and Cleveland 878 Cincinnati, via Wheeling and Central Ohio Rail- road 629 Cincinnati, via Wheeling and Ohio River boat.... 763 Cleveland, via Baltimore * and Ohio Railroad 523 Cleveland, via Pennsyl- vania Railroad 469 Cumberland, Md 178 Elmira, N. Y 247 Harper’s Ferry 82 Jonesboro’, Tenn 524 New York 184 Niagara Falls 415 294 HAND-BOOK OF THE LOCOMOTIVE, MILES. From Baltimore to Philadelphia 97 Pittsburg, via Pennsylva- nia Railroad 330 Raleigh, N. C 342 Rock Island, via Chicago 1059 Staunton, Va 197 St. Louis, via Wheeling and Ohio and Missis- sippi Rivers 1459 Washington, D. C. 40 Wheeling, via Baltimore and Ohio Railroad 380 Williamsport, Pa 169 From Washington, D. C., to Baltimore 40 Boston 460 Buffalo 442 Charleston, S. C 652 Chicago 864 Cincinnati, Ohio 509 Cleveland 509 Corralles, Oregon (Over- land Route) 3485 Detroit, Mich 684 Galveston, Texas 1800 Halifax, N. S 1113 Memphis, Tenn 1476 Mexico, City of Mexico... 2400 Montreal, Canada 627 New Orleans, La 1365 New York 224 Philadelphia 137 Quebec, Canada 772 MILES. From Washington, D. C. to Salt Lake City 2672 San Francisco (Overland) 3000 Santa F6, New Mexico ... 2192 St. Louis, Mo 1040 St. Paul, Minn* 1345 Toronto, Canada 623 OVERLAND ROUTE. Atchison to Fort Kearney 260 Denver, Colorado 650 North Platte 876 Green River. 1053 Great Salt Lake City, Utah 1250 Bear River 1340 Boisee City 1649 Virginia City 1733 Helena 1853 Sierra Nevada (Summit).. 2085 Sacramento City 2225 San Francisco 2365 St. Louis to Fort Kearney 598 Fort Laramie 1058 Red Buttes 1215 Fort Bridger 1493 Bear River 1528 Fort Hall 1684 Fort Boisee 2001 Fort Walla- Walla 2229 Fort Vancouver 2416 Oregon City 2446 HAND-BOOK OP THE LOCOMOTIVE, 295 DISTANCES FROM PHILADELPHIA TO CITIES AND TOWNS IN THE UNITED STATES BY THE SHORTEST ROUTES. MILES. Albany, N. Y 232 Absecom, N. J 52 Allentown, Pa 71 Alliance, Ohio 449 Atlantic City, N. J 59 Altoona, Pa 238 Augusta, Ga 742 Baltimore, Md 97 Bangor, Me 578 Bellefonte, Pa 250 Bethlehem, Pa 54 Beverly, N. J 13 Boonsburg, Pa 149 Bordentown, N. J, 27 Boston, Mass 323 Bridgeton, N. J 37 Bristol, Pa 17 Bristol, Va 620 Brooklyn, N. Y 89 Buffalo, N. Y 424 Burlington, N. J 19 Burlington, Iowa 1050 Camden, N. J 1 Cape May City, N. J 84 Carlisle, Pa 124 Catawissa, Pa 145 Catskill (Landing) N. Y.. 199 Charleston, S. C 563 Chambersburg, Pa 158 Chattanooga, Tenn 760 Chester, Pa 14 MILES. Cheyenne, Dakota 1824 Chicago, 111 823 Cincinnati, Ohio 668 Claymont, Del 20 Clearfield, Pa 264 Cleveland, Ohio 505 Coates ville. Pa 40 Columbia, Pa 80 Columbus, Ohio 584 Corning, N.Y 292 Corry, Pa 413 Cresson, Pa 253 Crestline, Ohio 544 Crisfield, Md 163 Cumberland, Md 276 Danville, Pa 154 Davenport, Iowa 1006 Delanco, N. J 12 Delaware Water Gap, Pa. 100 Detroit, Mich 675 Des Moines, Iowa 1180 Dover, Del 76 Downingtown, Pa 33 Doylestown, Pa 32 Dunkirk, N". Y 461 Eagle, Pa 17 Easton, Pa 66 Ebensburg, Pa 264 Egg Harbor, N. J 41 Elizabeth, N. J 73 Ellicott’s Mills, Md... 113 296 HAND-BOOK OF THE LOCOMO'^IVE, MILES. Fkom Philadelphia to Elmira, N.Y 275 Elkton, Md 46 Erie, Pa 451 Flemington, N. J 58 Florence, N. J 23 Fort Harker, Kan 1499 Fort Riley, Kan 1414 Fort Wayne, Ind 675 Franklin, Pa., via Pitts- burg 480 Frederick, Md 160 Fredericksburg, Va 208 Freehold, N. J 59 Galveston, Texas 1734 Gettysburg, (via Colum- bia, Pa.) 122 Girard, Pa 113 Glassboro, N. J 18 Grafton, Va 377 Greensburg, Pa 324 Gwynedd, Pa 18 Haddonfield, N. J 7 H agersto wn ,Md — 180 Hammonton, N. J 30 Hamilton, Canada 489 Harrington, Del 92 Harrisburg, Pa 106 Harper^s Ferry, Va 179 Hartford, Conn.. 198 Havre de Grace, Md 62 Hightstown, N. J 41 Hollidaysburg, Pa 246 Hornellsville,N.Y 333 Huntingdon, Pa 204 Indiana, Pa 320 MILES. Fkom Philadeli^hia to Indianapolis, Ind 736 Jackson, Miss 1344 Jamesburg, N. J 48 Jefferson City, Mo 1125 Jersey City, N. J 87 Johnstown, Pa 277 Kane, Pa 356 Kansas City, Mo 1280 Knoxville, Tenn 740 Lambertville, N. J 46 Lancaster, Pa 69 Laramie, Dakota 1886 Lawrence, Kan 1313 Leavenworth, Kan 1307 Lebanon, Pa 86 Lewistown, Pa 167 Linwood, Pa 18 Little Rock, Ark 1300 Lockhaven, Pa 228 Long Branch, N. J 82 Louisville, Ky 775 Lowell, Mass 358 Lynchburg, Va 316 Lynn, Mass 343 Madison, Wis 961 Mahanoy, Pa 117 Martinsburg, Va 198 Mauch Chunk, Pa ... 87 Media, Pa 14 Meadville, Pa 444 Memphis, Tenn 1152 Middletown, Pa 97 Milford, N. J 65 Millville, N. J 40 Milton, Pa 176 HAND-BOOK OF THE LOCOMOTIVE. 297 MILES. Fkom Philadelphia to Milwaukee, Wis 908 Mobile, Ala 1472 Morgan’s Corner, Pa 14 Montgomery, Ala 1037 Moorestown, N. J 10 Morristown, N. J 118 Morrisville, Pa 26 Mount Holly, N. J 18 Mount Joy, Pa 82 Nashville, Tenn 960 Natrona, Pa 378 Newark, Del 40 Newark, N.J 79 New Brunswick, N.J 56 Newburyport, Mass 368 Newburg, N. Y 148 New Castle, Del 34 New Haven, Conn 160 New London, Conn 160 New Orleans, La 1527 Newport, R. I. (rail and boat) 251 New York City 88 Niagara Falls, N. Y 446 Northumberland, Pa 163 Norristown, Pa 17 Ogden, Utah 2346 Oil City, Pa 440 Omah.i, Nebraska / 1316 Paoli, Pa 20 Parkersburg, Va 481 Parkersburg, Pa 45 Paterson, N. J 104 Pemberton, N.J 24 Pensacola, Fla 1106 MILES. Fkom Philadelphia to Perry ville, Md 61 Petersburg, Va 290 Phillipsburg, N. J 81 Philipsburg, Pa 227 Phoenixville, Pa 28 Pittsburg, Pa 355 Pittstown, Pa 151 Pittson, N. J 26 Port Clinton, Pa 78 Portland, Me 440 Portsmouth, N. H 384 Pottstown, Pa 40 Pottsville, Pa 98 Poughkeepsie, N. Y 163 Princess Anne, Md 144 Princeton, N. J 40 Providence, R. 1 272 Promontory, Utah 2400 Quakake, Pa 106 Quakertown, Pa 38 Rahway, N.J 68 Raleigh, N. C 451 Reading, Pa 58 Richmond, Va 268 Ridgeway, Pa 332 Riverton, N. J 7 Rochester, N. Y., via Wil- liamsport, Pa 373 Rochester, Pa 381 Rupert, Pa 147 Sacramento, Cal 3090 Salt Lake City 2369 St. George’s, Del 44 St. Louis, Mo 998 St. Mary’s, Pa 323 ^98 HAND-BOOK OF THE LOCOMOTIVE. MILES. From Philadelphia to St. Paul, Minn 1302 Salem, Mass 348 Salem, N. J 43 Salisbury, Md 131 San Francisco, Cal 3228 Saratoga, N. Y 264 Savannah, Ga 879 Schuylkill Haven, Pa 89 Scranton, Pa 164 Seaford, Del 112 Sheridan, Kan 1685 Sing Sing, N. Y 120 Smyrna, Del 66 South Amboy, N. J 63 Springfield, Mass 224 Steamboat, Pa 27 Stroudsburg, Pa 102 Sunbury, Pa 163 Suspension Bridge, N. Y. 448 Syracuse, N. Y 380 Swedesboro, N. J 18 Tacony, Pa 6 Tamaqua, Pa 98 Titusville, Pa 458 MILES. From Philadelphia to Toronto, Canada 528 Trenton, N. J 28 Troy, N. Y 238 Tullytown, Pa 21 Tunkhannock, Pa 176 Tyrone, Pa 524 Uintah (Salt Lake) 2340 Valley Forge, Pa 24 Vicksburg, Miss 1388 Vincennes, Ind 716 Vineland, N.J 35 Warren, Pa 385 Washington, D. C 138 Waterford, N. J 23 Weldon, N.C 354 Westchester, Pa 27 Wheeling, Va 424 Whitehall, Pa 11 White Haven, Pa 110 Wilkesbarre, Pa 142 Williamsport, Pa 197 Wilmington, Del 28 Wilmington, N. C 516 Woodbury, N.J 8 Number of Miles of Railroad in the World in 1873 . — The whole number of miles of railroad in the world at the close of 1873, was about 167,500, or nearly seven times the circumference of the earth. North America, 86,000 miles; Europe and entire Eastern hemisphere, 79,000; South America, 2,500, all of which were constructed at a cost of $6,400,- 000 , 000 . HAND-BOOK OF THE LOCOMOTIVE. 299 VOCABULARY OF TECHNICAL TERMS AS AP- PLIED TO THE DIFFERENT PARTS OF LOCO- MOTIVES. Air Chamber. — An air-tight vessel attached to the feed-pump, for the purpose of cushioning the pump and lessening the jar caused by the action of the plunger and the pressure in the boiler. Apron. — The sheet-iron plate that covers the space between the engine and tender. Arch Pipes. — The steam -pipes which connect the double cone with the cylinders. Ash Pan. — A box or tray beneath the furnace to catch the falling ashes and cinders. Axles. — The revolving shafts to which the wheels of locomotives and cars are attached. Back Dome. — The dome in which the dry-pipe is placed. Back Furnace Brace. — A brace that runs from the back of the furnace to the end of the frames. Bell Yoke. — A cast-iron yoke on top of the boiler, in which the bell swings. Bissel Truck. — A truck especially designed to relieve the lateral rigidity in locomotives and enable them to pass curves with ease. Blast Pipes. — Two pipes inserted in the exhaust ports, with their upper ends contracted, for the purpose of ex- citing an artificial draft. Blow-olT Cocks. — A cock at the bottom of the fire-box through which to empty the boiler. Blower Pipe. — A pipe in the smoke-box connected with the blower-cock in the cab to blow steam through, 300 HAND-BOOK OF THE LOCOMOTIVE. for the purpose of producing a draft when the engine is not in motion. Boiler. — The source of all power where steam is used as a motor. The vessel in which the steam is gen- erated. Bonnet. — A wire cap or netting surmounting the chimney, to keep down the sparks and cinders. Boxes. — The bearings resting on the journals of loco- motive and car axles. Brackets. — The braces which support the head-lights on the front end of locomotives. Brasses. — A term applied to the boxes on the cross- heads and crank-pins of locomotives. Brake. — A drag applied, by moving of rods and levers, to the wheels of railway cars, for the purpose of checking their velocity Brick Arch.- -A brick slab placed across the front end of the furnace, directly over the fire, for the purpose of holding the smoke and gases in contact with the fire until they become thoroughly mixed. Bumpers. — Timbers bolted to the frame on the front end of* engines and rear end of tenders. Bumper Blocks. — Pieces of timber bolted to the bumpers for the purpose of receiving the jar when the cars strike. Bumper Sheet. — A sheet placed on the front end of the frame to cover the space between the bumper and the cylinders. Cab. — A house for the engineer and fireman on the back end of the boiler of the locomotive. Cab Handles. — Handles fastened on the cab to assist the engineer and fireman in getting on or off the engine. HAND-BOOK OF THE LOCOMOTIVE. 301 Cellars. — Chambers in the jaws of the boxes, to hold oil for the purpose of lubricating the journals. Cellar Bolts. — The bolts which hold the cellars up to the journals. Centre Casting. — The casting that forms the connec- tion between the truck- bolster and the front end of the boiler. Check Valve. — A valve connected with the boiler to prevent the back pressure in the boiler from interfering with the action of the pump. Check Chamber. — A chamber attached to the waist of the boiler, through which the water passes from the connecting pipe to the boiler. Connecting Pipe.— The water-pipe that connects the pump with the check-valve. Connecting or Main Rods. — The rods that communi- cate the pressure on the pistons to the crank-pins of the main driving-wheels. Counter-balances. — Large blocks of iron, cast or secured to two or more arms of each driving-wheel, op- posite the crank-pin, for the purpose of balancing the weight of the parallel and main rods and steadying the motion of the engine. Cow-Catcher. — See Pilot. Crank Pins. — The pins that convert the rectilineal motion of the pistons to the rotary motion of the driving- wheels. Cross Heads. — Blocks moving in guides, having the end of the piston-rods secured within them at one end, and pins to attach the connecting-rods at the other. Cross-Head Pins. — The pins or wrists in the cross* heads to which the main rods are attached. 26 302 HAKD-BOOK OF THE LOCOMOTIVE. Crown Bars. — Bars on the upper side of the crown- sheet in the water space, with their ends resting on the edges of the furnace-sheet, for the purpose of strengthen- ing the crown-sheet. Crown-Bar Braces. — Braces attached to the crown- bars and to the top shell of the boiler, to give additional strength to the crown-sheet and the top of the boiler. Crown Sheet. — The top sheet of the furnace directly over the fire, to which the crown-bars are attached. Cut Off.— See Slide Valve. Cylinders. — Two steam-tight tubes attached to the front end of the boiler at the smoke-box, in which the pistons move, through which the mechanical effects of the steam are transmitted to the cranks by means of steam- tight pistons. Cylinder Cocks. — Small cocks on the lower side of the cylinders, through which the condensed water escapes. Cylinder Heads. — The front and back head of the cylinders, the latter containing the stuffing-boxes, through which the piston-rods move. Dampers. — Doors in the front and rear end of the ash-pan to regulate the quantity of air admitted to the furnace. Damper Handle.— A handle passing through the foot- plate to open or close the dampers. Dashers. — Sheet-iron plates attached to the inside shell of the boiler opposite the pump-check, for the pur- pose of preventing the cold water from striking the tubes. Deflector. — An arrangement used in the furnaces of locomotives for the purpose of mixing the air and gases, and causing the latter to ignite and render the combus- tion of the fuel more perfect. HAND-BOOK OF THE LOCOMOTIVE. 303 Dome. — The elevated chamber on the top of the boiler from which the steam is taken to the cylinders. Dome Bodies. — The sheet-iron jacket that surrounds the domes of locomotives outside of the wooden lagging. Dome Stays. — Braces connected with the crown-bars at one end, and the dome at the other, for the purpose of strengthening the dome and the crown-sheet. Dome Top. — A covering to which the safety-valves and whistle-stand are attached. Double Cones. — The steam-tight joint that connects the steam-pipe and arch-pipes with the flue-sheet in the smoke-box. Double Truck. — A truck with two pair of wheels. Drag Iron. — The bar that connects the engine with the tender by means of a drag-pin. Drag Pin. — The pin by which the drag-iron is at- tached to a yoke under the foot-plate. Draw Bar. — A bar on front of the pilot for the pur- pose of connecting the locomotive with cars or with another engine. Driving Saddle. — A yoke or stand which straddles the frame, and on w^hich the driving-springs rest. Driving Wheels. — The wheels through which the lo- comotive obtains its power, by their adhesion to the rails. Eccentric. — Cams on the main axles of the driving- wheels, through which the slide-valves receive their mo- tion. Eccentric Straps. — The straps that encircle the ec- centrics, and to w^hich the eccentric rods are attached. Eccentric Rods. — Rods having one end attached to the eccentric strap and the other end to the link. Equalizing Levers. — Bars suspended by their centre 304 HAND-BOOK OF THE LOCX)MOTIVE. beneath the frame, and connected at each end to the springs of the drivers to distribute any shock or jolt re- ceived by the wheels. Equalizing Springs. — Springs used on the reverse shaft to equalize the weight of the links. They are either spiral or elliptic, according to circumstances. Exhaust Cavity in Valves. — A cavity in the valve- face to allow the steam to escape from the cylinders, over the bars or bridges, to the exhaust-pots. Exhaust Nozzles. — Nozzles inserted in the exhaust pots, for the purpose of decreasing the openings in order to excite the draft in the furnace. Exhaust Ports. — Openings in the middle of the valve- seats, through which the exhaust steam escapes from the cylinders to the exhaust-pots. Exhaust Pots. — Cone-shaped pipes attached to the ex- haust cavities of the cylinders in the smoke-box. Expansion Clamps. — Clamps attached to the fire-box under the main frame, for the purpose of holding the frame against the liners. Expansion Clamps. — Clamps bolted over the mam frames and furnace pads to allow for the expansion of the boiler. Expansion Joints. — A joint on the throttle-pipe to allow for expansion. Feed Pipes. — Pipes or hose connected at one end with the tank and at the other with the receiving chamber of the pump, through which the water passes from the tank to the pump. Feed Pipe Hangers. — Hangers bolted to the bottom of the frame, for the purpose of supporting the feed- pipes. HAND-BOOK OF THE LOCOMOTIVE. 305 Feed Water Cocks. — Cocks in the ends of the pipe to regulate the supply of water to the pumps. Feed Water Shafts. — Upright shafts passing through the foot-plate to the feed-water cocks, and operated by means of cranks. Fire Box. — The furnace of the locomotive; the cham- ber in which the fuel is consumed. Fire Door. — A door on the back end of the boiler through which the fuel is introduced into the furnace. Foaming. — An artificial excitement or ebullition of the water in the boiler when the water becomes foul or greasy. Follower Bolts. — The bolts that secure the follower plates to the piston-heads. Follower Plates. — The plates that cover the spring- packing on the front end of the piston-heads. Foot Board. — A board at the back end of the boiler on which the engineer stands. Foot Plate. — A cast-iron plate bolted to the back end of the frame in front of the fire-door, and to which the drag-iron is attached by means of the drag-pin. Frame. — Parallel pieces to which the cylinders, cross- ties, and all the main parts of the locomotive are attached. Frame Braces. — Horizontal braces between the ped- estals. Front Door. — A door on the front end of the boiler inclosing the smoke-box. Front Pail. — The front attachment of the frame ex- tending from the front bumper back to the front drivers. Frost Cocks. — Cocks to admit steam from the boiler to the feed-pipes, to prevent freezing in cold weather. Frost Plugs. — Plugs screwed into the pump-chambers 26* U 306 HAND-BOOK OF THE LOCOMOTIVE. and pump-cages, to allow the water to escape from the pump-chamber and prevent freezing. Fulcrum. — The prop, support, or fixed point upon which the levers of the safety-valves are sustained, and on which they are supposed to turn freely. Fulcrum of Equalizing Beams. — Tongues on the frame between the driving-wheels on which the equaliz- ing beams vibrate, by which the weight of the engine is equalized on the drivers. Furnace Pads. — Knees bolted on the shell of the fire-* box, by which the weight of the boiler rests on the frame. Furnace Bings. — The wrought-iron ring that forms the connection between the outside and inside sheets in the water space at the bottom of the furnace. Fusible Plug. — A plug sometimes used in the crown- sheets of locomotive boilers for the purpose of giving warning in case the water in the boiler should become dangerously low. The metal of the fusible plug consists of 8 parts of bismuth, 5 of lead, and 3 of tin ; it melts at the heat of boiling water, or 212° Fah. Gasket. — A gum packing for the man-hole or hand- holes of boilers. Gauge Cocks. — Cocks at different levels on the back end of the boiler, to ascertain the height of the water in the boiler. Gib. — The fixed wedge for taking up the wear in boxes on cross-heads and crank-pins. Gland. — A bushing to secure the packing in stuffing- boxes. Glass Gauge. — A glass tube on the back end of the boiler, connected with the steam- and water- valves, to in- dicate the height of the water. HAND-BOOK OF THE LOCOMOTIVE. 307 Goose Neck. — A brass or cast-iron neck connecting the front end of the feed-pipe to the lower chamber of the pump. Grate. — The parallel bars on which the fuel is burned when soft coal or wood is used. Gromnet. — A ring of hemp used as a packing. Guide. — A sleeve on the front end of the steam-chest, in which the end of the valve-rods move. Guide. — The piece to which the throttle-valve lever is made fast, to prevent slipping when the engine is in mo- tion. Guide Bars. — The parallel pieces between which the cross-hedges move. Guide Bearer. — A bar or brace bolted across the frames, to which the guide-blocks are attached. Guide Blocks. — The blocks on the back head of the cylinder and on the guide-bearer, to which the guide-bars are attached. Guide Brace. — A brace attached to the guide-bearer at one end, and the boiler at the other, for the purpose of supporting the guide-bearer. Hand Holes. — Holes in the outside shell of the fur- nace near the ring, through which to remove the deposits of rust or dirt that may accumulate in the water-legs of the furnace. Hand Bail. — A rail running lengthways of the boiler, supported by studs, used as a safeguard to the engineer in getting on or off the foot-board when the engine is in motion. Head Light. — A light used on the front end of loco- motives. Heater Cocks. — Cocks attached to the boiler in the 308 HAND-BOOK OF THE LOCOMOTIVE. cab for the purpose of blowing steam through the feed- pipes to the pumps in cold weather. Heater Pipes. — Pipes connecting heater cocks with feed- water pipes. Hollow Stays. — Hollow stay-bolts passing through the outside and inside sheets of the furnace near the crown-sheets, to admit air to the furnace for the purpose of increasing the combustion of the fuel. Horns. — Knees on the top side of the frame, back of the front bumper. House Boards. — Boards on the sides of the boiler at- tached to the house-brackets, on which the house rests. House Brackets. — Cast-iron brackets attached to the back bumper of the engine, and on which the house- boards rest. House Knees. — Wrought-iron knees used in attaching the house-boards to the shell of the boiler. Induction Ports. — The passages in the valve-seat through which the steam enters the cylinders. Injector. — An instrument used in supplying boilers with feed water. See Injector. Jacket. — A covering for steam cylinders. Jam Nuts. — Nuts used for setting out the spring- packing in piston-heads. Jam Wrenches. — Wrenches used for locking the nuts of the spring-packing on piston-heads. Jaw. — A stand secured to the frames of railway cars to hold the boxes in which the journals of the axles revolve. Journals. — That part of the axles on which the boxes rest. Keys. — The wedges for tightening the straps which hold the brasses at the ends of the connecting-rods. HAND-BOOK OF THE LOCOMOTIVE. 309 Key Way. — A slot in a shaft to receive the key where two pieces of machinery are connected by means of a key or keys. King Pin. — A pin passing through the centre casting and the truck centre, for the purpose of preventing the latter from becoming detached from the former. Knuckle Joints, — Joints on the valve-rods to allow them to vibrate freely with the radius of the rocker-arm. Lagging. — A wooden sheathing placed round the boiler and cylinders of locomotives, for the purpose of excluding the atmosphere and preventing condensation. Lap. — The distance which the slide-valves overlap the receiving ports when in the middle of their travel. Lead. — The amount of opening the slide-valves have on the steam end when the pistons commence the stroke or the cranks are on the dead centre. Lifting Links. — The links which connect the lifting- arms of the reverse shaft to the saddle-pins of the links, by means of which the links are raised and lowered. Lifting Pipe, Clearance Pipe, or Petticoat Pipe. — A funnel-shaped pipe over the exhaust-pots in the smoke- box, that can be raised or lowered to equalize the draft in the tubes. Liners or Frame Liners. — Pieces of iron placed between the frames and the ftirnace to keep the boiler in its proper position between the frames. Link. — A variable radius expansion gear used on lo- comotives for the movement of the steam-valves. Link Block. — A block working between the jaws of the link and connected with the upper arm of the rocker. Lubricator. — The valve or globe through which the 310 HAND-BOOK OF THE LOCOMOTIVE. oil or tallow is admitted to the cylinders, either from the steam- chest or cab. Main Frames. — The frame that runs from the front end of the drivers to the back end of the engine. Mud Cock. — A cock in the mud-drum through which to discharge the mud from the drum. Mud Drums. — A small cylinder attached to the under side of the waist of the boiler, to receive the de- posits carried into the boiler by the feed water. Mud Holes. — Openings in the back end of the fire- box, generally closed by brass plugs, through which to re- move the mud from the lower water space. Offsets. — Eecesses in the outside shell of the fire-box to allow the spring-saddles room between the fire-box and frame. Packing. — A substance used to make a steam-tight joint around the piston- and valve-rods. Packing Hook. — A steel hook used for removing the old packing from the stuffing-boxes when it becomes necessary to repack the engine. Packing Rings. — The rings on the piston-head that form the steam-tight joint in the cylinder. Packing Stick. — A small stick used to drive the packing into the stuffing-boxes. Pedestal Caps. — Caps on the bottom of driving and truck pedestals. Pet Cock. — A small cock communicating with the valve chamber of the pump to show whether the pump is working or not. Pilot. — A fender bolted on the front bumper to re- move obstructions from the track. Pilot Brace. — A brace running from the heel of the pilot to the front bumper. HAND-BOOK OF THE L0C07T0TIVE. 311 Pin Plate. — A plate on the link to which the lifting- arm is attached. Piston Heads. — Cast-iron heads attached to the piston- rods, on which the rings are fitted that form the steam- tight joint in the cylinders. Piston Rod. — A rod keyed at one end to the piston- head, and at the other end to the cross-heads. Pockets. — Recesses in the top of the driving and truck-boxes, in which the driving-saddles and equalizing beams rest. Poney Truck. — A truck with one pair of wheels. Priming. — Water carried over with the steam from the throttle-pipe to the cylinders. Pulling Pin. — A pin in the foot-plate to which the drag-iron is attached. Pump Cages. — Brass chambers between the pump- barrel and air-vessel, in which the valves are placed. ftuadrant. — A slotted segment in the cab, which holds the reverse lever in the right position by means of the reverse latch. Quadrant. — A ratchet segment in the cab by which the variable exhaust is regulated. Radius Bar. — An angle bar attached to the back end of the truck frame and to the radius bar cross-tie by means of a pin. Radius Bar Cross -tie. — A bar slotted across the frame as a brace for the radius bar. Reach Rod. — A rod connecting the reverse lever with the reverse arm of the reverse shaft. Receiving Ports. — The openings in the valve-seat through which the steam passes from the steam-chests to the cylinders. 312 HAND-BOOK OF THE LOCOMOTIVE.- Reverse Latch. — A tongue fitted to notches in the quadrant, by which the reversing lever is held in position. Reverse Shaft. — A shaft running parallel with the driving-axles at the top side of the frame, by means of which the links are raised or lowered. Reversing Lever. — A lever in reach of the engineer, by which the motion of the engine can be changed and the travel of the valves increased or decreased. Rockers. — Double cranks, connected with the link- blocks at one end and the valve-rods at the other, by which the valves receive their motion through the inter- vention of the eccentrics and links. Rocker Boxes. — Boxes attached to the frames in which the rocker-shafts vibrate. Saddle Pin. — A pin on the back of the saddle-plate, to which the lifting link is attached, and by means of which the main link is raised or lowered. Saddle Plate. — The plate that forms the base of the saddle-pin on the link. Safe Ends. — Copper ferrules brazed to the end of the iron tubes to form the lip on the tube-sheets. Safety Chains. — Chains attached to the front bumper and the front end of the truck frame, for the purpose of preventing the truck from swinging round and breaking the links in case the locomotive should run ofi* the track. Safety Hooks. — Hooks bolted to the back bumper of the engine ; the safety chains of the tender are attached. Safety Valves. — Valves on the dome-cover to dis- charge the surplus steam from the boiler. Sand Box. — A cylindrical box or dome attached to the top of the boiler, for carrying sand for the engine. Sand Box Rod. — A rod communicating with the sand- box in the cab, by which the sand-valves are moved. Sand Pipes. — Pipes communicating with the sand- HAND-BOOK OF THE LOCOMOTIVE. S13 box, through which the sand passes to the rails in front of the drivers, to prevent the wheels from slipping when the rails are damp or greasy. Scroll Irons. — Iron bands placed round the ends of the front bumper under the bumper-sheet. Shell. — The outside sheets of the boiler. Slide Valves. — Slide-valves are the valves which control the admission and escape of steam to and from the cylinders. Smoke Box. — A chamber at the forward end of the boiler which contains the arch-pipes, lifting-pipes, ex- haust-pots, and* blower-pipes, and through which the smoke escapes from the furnace to the smoke-stack. Smoke Box Bing. — A wrought-iron ring in the front end of the smoke-box, to which the frame of the front door is attached. Smoke Box Brace — A brace running from the smoke- box to the frame back of the horn. Smoke Stack. — The chimney through which the smoke escapes from the smoke-box. Smoke Stack Base. — A saddle casting on the smoke- arch, to which the lower end of the smoke-stack is at- tached. Spark Arrester. — A wire netting or screen in the stack to retain the sparks. Springs. — Combinations of steel-plates connected at their centre by bands, and at the ends to the equalizing beams, for the purpose of lessening the jar on the engine produced by the inequality of the track. Spring Balances. — Spring attachments in the cab connected at one end with the safety-valve levers, and at the other end with the top sheet of the boiler. 27 814 HAND-BOOK OF THE LOCOMOTIVE. Spring Hangers. — The pieces that connect the end of the springs with the equalizing beams. Spring Saddles or Spring Staples. — Yokes that straddle the frames and form a support for the springs on the top of the driving-boxes. Stack Cone. — A casting used in the smoke-stack for the purpose of retarding the passage of the sparks as they escape from the furnace to the open air. Steam Chests. — Boxes on the top of the cylinders containing the slide-valves, from which the steam is ad- mitted to the cylinders. Steam Gauge. — A gauge on the back end of the boiler, in the cab, to indicate the pressure df steam per square inch on the boiler. Steam Pipes. — The pipes through which the steam passes from the dome to the arch-pipes in the smoke- box. Stop Cocks. — Cocks on the water-pipes between the tender and pumps. Stop Valves. — Valves used for different purposes in connection with the locomotive. Straps. — The pieces that secure the brasses on the cross-head pins and wrists of the main drivers. Stroke. — Half the distance travelled by the pistons at each revolution of the main drivers. Stub Ends. — The ends of the main rods that butt against the boxes on the cross-heads and wrist-pins. Stuffing Boxes. — Chambers in the back head of the cylinders and steam-chests, through which the piston- rods and valve-rods move. Supply Ports. — Openings in the steam-chests through which the steam enters from the arch-pipes. HAND-BOOK OF THE LOCOMOTIVE. 315 Swing Bolster. — A swinging bolster in the centre of the truck, on which the forward end of the engine rests, and which allows the locomotive to round sharp curves with ease. Tender. — A carrif*^e attached to the back end of the locomotive, for the purpose of carrying water and fuel. Thimble. — An iron ring or bushing used for stopping leaks in the tubes of locomotive boilers. Throttle Lever. — The lever by which the throttle - valve is opened and closed. Throttle Pipe. — A vertical pipe having its lower end connected to the steam-pipe, and its upper end sustained by braces in the dome. Throttle Valve. — A balance valve in the throttle- pipe, through which the steam is admitted to the steam- pipe. Tires. — Wrought-iron or steel bands surrounding the driving-wheels of locomotives. Trailing Wheels. — A pair of small wheels placed behind the drivers in cases where but one pair of driving- wheels is used. Truck. — The frame, wheels, and springs on which the front of the locomotive rests. Truss Rods. — Braces used for strengthening the truck. Tubes. — The iron or copper flues through which the smoke escapes from the furnace to the smoke-box. Tube Sheets. — The sheets in which the tubes are in- serted. Valves. — See Slide and Stop Valves. Valve Yokes. — Wrought-iron bands surrounding the valves in the steam-chests, to which the valve-rods are at- tached. 516 HAND-BOOK OF THE LOCOMOTIVE. Variables Exhaust. — An arrangement by which the opening in the exhaust nozzles can be contracted for the purpose of exciting the draft in the furnace. Waist. — The cylindrical part of a locomotive boiler. Waist Sheet. — A sheet of wrought-iron bolted to the waist of the boiler by angle iron, to which the guide- braces, guide-bearers, and cross-ties are attached. Water Tubes. — Horizontal tubes used as grate-bars in the furnaces of anthracite coal burners. Water Tables. — A hollow table or apron riveted to the front end of the furnace and communicating with the water space, for the purpose of changing the current of the air and gases, and rendering the fuel more com- bustible. Wheel Covers. — A covering on the drivers and truck- wheels to prevent the machinery from being injured by the mud and sand. Whistle. — A bell or gong used to give warning and indicate the approach of the locomotive. Whistle Lever. — A lever attached to the whistle- base, to open the whistle-valvei. INDEX Absolute motion, 264. Accelerated motion, 264. AcceleratioUf 260. Accidents f rules to be followed in case of, 285. Adhesion, 260. Air, 33. and fuel, mixture of, 65. expansion of, etc., table show- ing, 37. pressure of, 34, 35. resistance to motion caused by, 38. Angle of friction, 260. Angular motion, 264. Anitnal strength, 260. Anthracite coal, 66. Areas of circles, tables of, 247, 248, 267, 271. Ash‘pans, 216. Atomic or molecular force of heat, 59. Attraction, 261. Axles, 260. driving, brasses for, 159. Jialanced slide-valve, 145. Baldwin anthracite coal-burning locomotive, 100. Bituminous coal, 70. Boiler flues, rule for finding safe external pressure on, 185. 27 * Boiler pressures, tables of, 188, 19L Boilers and boiler materials, defi- nitions as applied to, 186. incrustation in, 272. rule for finding safe working pressure of, 183. locomotive, 163. locomotive, evaporative power of, 170. locomotive, heating surface in, 172. locomotive, heating surface to grate surface in, 174. locomotive, instructions for care and management of, 222. locomotive, machine and hand- riveting for, 179. locomotive, proportions of, 167. locomotive, rule for finding heating surface in, 174. locomotive, rule for finding heatingsurface in tubes of, 175. locomotive, steam room in, 172. locomotive, straight, 162, 176. locomotive, wagon-top, 1G7, 168. locomotive, water space in, 172. stationary, 175. steel, rule for finding safe work- ing pressure of, 184. Boiling point of water, 29. Brasses for driving-axles, 159. Bridges, 133. 317 318 INDEX. bruises, 287. Burns, 287. Caloric, 51. conductors and non-conductors of, 51. latent, 52. radiation of, 51. reflection of, 51. sensible, 52. Carbon, 77. Carhuretted hydrogen, 77. CasUiron, table showing tensile strength of, 257. Centre of gravity, 262. of oscillation, 264. of percussion, 265. Central or centrifugal force, 261. Centripetal force, 261. Chemical combinations accom- panied by production of heat, 363. equivalents, 64. Circle, diameters, circumferences, and areas of, 247. mensuration of, 242. Circumferences of circles, table of, 247, 248. Clear ance^pipe, 216. Clinton, De Witt, locomotive, 288. Coal, 64. anthracite, 66. anthracite, composition of dif- ferent kinds of, 66. anthracite, evaporative effi- ciency of, 68. anthracite, quantity of air re- quired for combustion of, 67. bituminous, 68. bituminous, composition of, 68. Cohesion, 261. Cohe, 69. Combustion, 63. available heat of, 65. of fuel in locomotive furnaces, 210 . spontaneous, 73. Compound motion, 264. ( Construction of locomotives, 118. Crank^pin, rule to find diameter of, 117. Crotvn^bars, 203. Crushing strength, 26. CugnoVs locomotive, 158. Cylinder, mensuration of, 242. Dampers, 217. Dan forth passenger locomotive, 48 Decimal equivalents, table of, 245. Detrusive strength, 261. Diameter of circles, table of, 247, 267. Distance by railroad between im- portant places in U. S., 292. Distances from Philadelphia to cities and towns in U. S. by shortest routes, 295. Driving '■axles, brasses for, 159. Dynamic equivalent of heat, 58. Ebullition or boiling of water, 27. Eccentric^rods, 136. length of, 137. positions of, on shaft, formula to find, 137. Eccentrics, 134. Elastic fluids and vapors, 49. Elasticity, 186. Elasticity of steam, 82. Engine, power of the, 96. tank, 128. Engines, stationary, 99. Engineers, locomotive, 21, hints to, 234. INDEX, 319 Equivalent, dynamic, of heat, 58. mechanical, of heat, 56. Equivalents, decimal, table of, 245. Evans% Oliver, locomotive, 254. Evaporation of water, 27. why produces cold, 52. Ekchaust-nozzle, 216. ExhausUpovts, rule to find area of, 117. Expansion, power of, by heat, 58. Experiments on iron boiler- plates (tables), 255, 256. Explosions, boiler, 278. Fairlie narrow-gauge locomotive, 136. Feed-pump ram, rule to find di- ameter of, 117. Fire, 74. Fire^hoxes, materials for, 198. proportions of, 198. Firemen on locomotives, 224. on locomotives, natural qualifi- cations of, 227. Firing, 228. Fixed temperatures, 47. Flues, boiler, rule to find safe ex- ternal pressure on, 185. Fluids, conditions of equilibrium of, 50. elastic, 49. Force, 261. central or centrifugal, 261. centripetal, 261. of heat, molecular or atomic, 59. Forces, central and mechanical, 260. Forney ^s improved tank locomo- tive, 125. Friction, 261. angle of, 260. Fuel and air, mixture of, 65. Fuel, combustion of, in locomotive furnaces, 210. ingredients of, 65. unburnt waste of, 73. Furnaces in locomotive boilers, 192. stayed sul’falces in, strength ol^ I 199. ' \. Gas, olefiant, 78. Oases, 76. compression and dilatation ofi 79. gravity acts on, 49. liquefaction of, 79. specific gravity of, 80. Giffard^s injector, 232. Gradients, table of, 105. Grate-bars, 216. Gravity, 262. centre of, 262. specific, 265. specific, of different seas, 26. specific, of ice, 30. specific, of water, 26, 31, Gyration, 262. Heat, 52, 81. communication of, 59. dynamic equivalent of, 58. effects of, in circulation of water in boilers, 60. effects of, upon different bodies, 61. latent, 55. latent, of various substances, 61. mechanical equivalent of, 56. mechanical theory of, 57. medium, 61. molecular or atomic force of, 59. power of expansion by, 58, sensible, 56. 320 INDEX, Heatf specific, 53. total or actual, 59. transmission of, 61 . unit of, 54. Morse-power, actual or net, 98. indicated, 98. nominal, 98. of stationary engines, 99. of steam-engines, 99. Hydroaarbons, 65. Mydrodynainics, 262. Hydrogen, 77. carburetted, 77. Hyperbolic logarithms, 263. Ice, latent heat of, 27. specific gravity of, 30. Impetus, 263. Inclined plane, 263. Incrustation of steam-boilers,272. Indicator, the, 263. Indicators, speed, 161. Inertia, 262. Injector, action of the, 231. accumulation of power, 232. Kue’s “ Little Giant,” 230. how to put on, 233. method of working, 234. table of capacities, 237. Injectors, table of capacities of, 235 Instructions for care and man- agement of locomotive boil- ers, 222. ** Ironsides,** locomotive, 291. lap of valve, 144. and lead, table showing amount of, 146. latent caloric, 52. ^ heat, 55. heat of water or ice, 27. Lateral motion, 160. lateral pressure of water, 251. Lead of valve, 145. Linh, the, 147. adjustment of thfe, 152. Liquefaction of gases, 78. Load, safe, 186. Locomotive, the, 17. adhesive power of the, 101. age of, 130. average proportion of different parts of, 117. Baldwin anthracite coal-burn- ing, 100. building, 117. “ Charles Millard” exploded, 279 construction of, 118. Cugnot’s, 158. cut of, 16. Danforth passenger, 48. dead weight in, 126. “ De Witt Clinton,” the, 288. eight-wheel passenger, 62. Evans’, Oliver, 254. freight anthracite coal -burn- ing, 93. heavy, 131. “ Ironsides,” 291. Murdock’s, 212. narrow-gauge, Fairlie, 136. number of, in the United States, 130. number of miles run by, -30. power of, 101. proportions of, 107-115. rule for calculating tractive power of, 102. rule for finding area of exhaust- ports of, 117. rule for finding diameter of crank-pin of, 117. rule for finding diameter of feed-pump ram of, 117. INDEX, 321 hoeottioUvef rule for finding di- ameter of piston-rod of, 117. rule for finding diameter of steam-pipe of, 117. rule for finding horse-power of, 102 . rule for finding power of, 106. rule for finding size of steam- ports for, 117. setting the valves of, 121. Stephenson’s, George, 277. theory of the, 24. tractive force of, 101. tractive power of, rules for cal- culating, 102. TjogwrithmSf 263. hyperbolic, 263. mechanical equivalent of heat, 52. power, 263. properties of vapor, 80. theory of heat, 57. Mensuration of the circle, cyl- inder, sphere, etc., 242. Mercury f expansion of, 46. properties of, 43. Molecular or atomic force of heat, 59. Momentum f 264. Motion, 264. absolute, 264. accelerated, 264. angular, 264. compound, 264. lateral, 160. natural, 264. perpetual, 265. relative, 264. retarded, 264. uniform, 264. Movers, prime, 265. Murdoch's locomotive, 212. Narrow’-gauge locomotive. Fair- lie, 136. Natural motion, 264. Nitrogen, 78. Nozzle, exhaust, 216. Number of mil^s of railroad in the world in lS73, 298. Olefiant gas, 78. PacIHng for pistons and valve- rods, 156. metallic, 157. piston-rod, rule to find size of, 158. spring cylinder, setting out, 155. steam and spring cylinder, 154. valve-rod, rule to find size of^ 158. Pendulum, 265. Percussion, 265. Perpetual motion, 265. PetticoaUpipe, 216. Piston-rod, rule to find diameter of, 117. Plane, inclined, 263. Pneumatics, 265. Power, 263. mechanical, 263. of expansion by heat, 58. of locomotive, rule for finding, 106. Pressure of air, 34, 35. safe working, 186. Prime movers, 265. Radiation of caloric, 51. Railroad, number of miles of, in the world in 1873, 298. trains, resistance of air against, 38. V INDEX, m Jtailroad trains, resistance of air against, table showing, 40. Jtailronds, speed on, 131. Iteflection of caloric, 51. Relative motion, 264. Resistance to motion caused by the air, 38. Retarded motion, 264. Rocket/^ the locomotive, 277. Rods, eccentric, 136 ; length of, 137. Rue*s “Little Giant” injector, 230-3. Rule to find area of exhaust- ports, 117. to find diameter of crank-pin, 117. to find diameter of feed-pump ram, 117. to find diameter of piston-rod, 117. to find diameter of steam-pipe, 117. to find elasticity of steel springs, 252. to find heating surface in loco- motive boilers, 174. to find heating surface in sta- tionary boilers, 175. to find heating surface in tubes of locomotive boilers, 175. to find horse-power of locomo- tives, 102. to find power of locomotives, 106. to find quantity, height, etc., of water in steam-boilers, 250. to find safe external pressure on boiler flues, 185. to find safe working pressure of steel boilers, 184. to find size of piston-rod pack- ing, 158. Rule to find size of steam-ports, 117. to find size of valve-rod packing, 158. to find tractive power of loco- motives, 102. Rules to be followed in case of ac- cidents, 285. Safety -valves f 217. table showing rise of, under different pressures, 220. Scalds, 287. Seams, boiler, punched and drilled holes for, 176. single and double riveted, 176. single and double riveted, com- parative strength of, 180. Sensible caloric, 52. heat, 56. Signals, 238. Slide-valve, 139. balanced, 145. friction on, 143. Smoke-box, 213. Smoke-stacks, 214. Specific gravity, 265. gravity of ice, 30. gravity of gases, 80. gravity of water, 26, 31. heat, 53. Speed indicators, 161. Sphere^ mensuration of, 242. Spontaneous combustion, 73. Springs, steel, rules for finding elasticity of, 252. Stay-bolts, 201. Stationary engines, 99. Steam, 80. elasticity of, 82. mechanical properties of, 80. pressure of, 86. INDEX, 323 Steam superheated, 88. temperature of, 86. Steam-engines f horse power of, 94. power of, 96. Steam-gauges, 221. Steam-pipe, rule to find diameter of, 117. Steam-ports, 132. rule to find size of, 117. Steel, 195. plates, table showing tensile strength of, 259. Stephenson^ s. Geo., locomotive, 277. Strength, 266. animal, 260. crushing, 261. detrusive, 261. tensile, 186. torsional, 266. transverse, 266. working, 186. Table containing diameters, cir- cumferences, and areas of circles, 267, 271. deducted from experiments on boiler plates, 255, 256. of areas of external surfaces and diameters of tubes, 207-209. of boiler pressures, 188, 191. of capacities of injectors, 235. of decimal equivalents, 245. of diameters, circumferences, and areas of circles, 247, 248. of gradients, 105. of temperatures required for the ignition of different com- bustible substances, 75. showing actual extension of wrought-iron at various tem- peratures, 256. Table showing amount of lap and lead on valves, 146. showing effects of heat upon different bodies, 61. showing expansion of air by heat, 37l i i showing number of revolutions per minute by drivers, 129 showing resistance of air against railroad trains, 40, 41. showing rise of safety-valves under different pressures, 220. showing specific gravity of dif- ferent seas, 26. showing temperature of steam, etc., 91, 92. showing tensile strength of cast-iron, 257. showing tensile strength of steel plates, 259. showing time at 80 different places when it is 12 M. at N. Y. city, 289. showing tensile strength of wrought-iron, 258. showing total heat of combus^* tion of various fuels, 74. showing velocity of escape and pressure of sttam, 89. showing weight of water, 31, 249. Tank, engine, 128. Temperatures^ fixed, 47. Tensile strength, 186. Theory, mechanical, of heat, 67. Thermometer, the, 43. absolute zero, 46. centigrade scale, 45. change of zero, 46. comparative scale of English, French, and German, 42. Fahrenheit’s, 44. 324 INDEX, Thermometerf mercurial, 44. Reaumer’s, 45. solid, 47. spirit, 47. standard points of, how ascer- tained, 44. Tools, wrecking, 239. Torsion, 266. Torsional strength, 266. Tractive power of locomotives, 102. TrammeUgauge, 122. Transverse strength, 266. Tubes, 203. breaking of, 205. burning of, 204. corrosion of, 205. leakage of, 205. length and diameter of, 205. resistance of, 204. sagging of, 205. steel,*203, 205. table of areas of external sur- faces and diameters of, 207-209 wearing of, 204. Uniform motion, 264. Unit of heat, 5^. Valve, lap and lead of, 144. position of, at full stroke, 139. position of, at half stroke, 140. position of, when link is in mid- gear, 141. travel of, 145. rods, length of, 144. rods, packing for, 156. slide, 139. slide, balanced, 145. slide, friction on, 143. Valves of locomotives, setting the, 121 . safety, 217. safety, table showing rise under different pressures, 220, Vapors, elastic, 49. Velocity, 266. Vocabulary, 299. Water, 25. boiling point of, 29. composition of, 26. discharge of, 251. ebullition or boiling of, 27. evaporation of, 27. for the production of steam, 26 latent heat of, 27. lateral pressure of, 251. passing into steam, 86. pressure of, 251. rules to find quantity, height, etc., in steam boilers, 250. specific gravity of, 26, 31. weight of (tables), 31, 32, 249. Weights and measures, 266. measures, etc., useful numbers in calculating, 240, 241. Worh, 266. WorUing-pressure, safe, 186. strength, definition of, 186. Wreching -tools, 239. Wrought-iron, table showing actual extension of, 256. table showing tensile sttbiigtli of, 258. Zero, absolute, 46. change of, 46. THE END.