we sea NI SARA SN RATES 84. ° Gea las roman Use and Abuse of the Steam-Boiler. OPINIONS OF THE PRESS. The Iron Age, N.Y, This work is intended to be a hand-book for the fireman, pur- chaser, and user of boilers, rather than for the boiler-maker or scientific man. The work is somewhat smaller than the other hand-books by the same author. It is, however, bound in uni- form style with them. Most of the common forms of boilers are illustrated, as well as many of those not usually seen. The author aims, he tells us, at a dissemination of plain, practical, and correct information in regard to the functions of the steam- boiler, its care and management. The work, as a whole, is valu- _ able, presenting in a compact form many of the tables, facts, and figures which have heretofore been scattered among a wide range of authorities. Engineering News, Chicago, Ill, Mr. Roper is the author of several well-known hand-books relating to the steam-engine, and steam machinery in general. In this, his latest work, he states that his object is “simply to show what the results of his thirty years’ personal experience with all classes of boilers prove to be the safest and most dura- ble materials for their manufacture, to show the absolute ne- cessity of good workmanship in their construction, and to call the attention of owners, engineers, and firemen to the rules that limit their usefulness, safety, and longevity.” As in all his other hand-books, the writer addresses himself to men of ordi- nary intelligence,— those found in charge of steam-engines and boilers,—and in consequence his book is written in the plainest and most intelligible language that can be chosen. We have not the time, nor possibly the necessary amount of practical knowl- edge of all the latest improvements in steam-boilers, to criticise closely and intelligently the contents of the book, but in con- nection with it we would call attention to the large number 1 USE AND ABUSE OF THE STEAM-BOILER,. of boiler explosions, attended with great loss of life, that have recently occurred in this country and in England, and which, upon investigation, have been proven to be the results of igno- rance and carelessness on the part of attendants, and we cannot but think that steam-users would find it greatly to their advan- tage if such plain handy-books as those of Mr. Roper’s were placed in the hands of every attendant upon a steam-boiler or engine, and his attention called to the advantage of making himself familiar with its contents. The Locomotive, Hartford, Conn, “UsE AND ABUSE OF THE STEAM-BOILER.’”’—Stephen Roper, of Philadelphia, is the author of several hand-books on Steam-Engineering, which we have noticed in the LOCOMOTIVE, from time to time, as they have been issued. Their great merit is, that they are adapted to the wants of those whose circum- stances had prevented them from obtaining such an education as will enable them to cope with the various formule that enter — into the higher branches of steam-engineering. Most works on steam shoot over the heads of this class of people. And yet, when we come to the matter of actually handling a boiler, or an engine in use, their practical experience is invaluable. We have said thus much by way of introducing a new work which Mr. Roper has just issued, viz., USE AND ABUSE OF THE STHAM-BOILER. This contains just the kind of information that a person having the care of steam-boilers needs, and such information as we have put forth in our various pub- lications from time to time. We heartily recommend it to all persons who have to do with steam-boilers, whether as proprie- tors or engineers. The hand-books which Mr. Roper has issued are as follows: ‘‘ Catechism of Steam-Engines,” ‘ Hand-Book of the Locomotive,” ‘‘ Hand-Book of Modern Steam Fire-En- gines,” “ Hand-Book of Land and Marine Engines,” “ Use and Abuse of the Steam-Boiler.” Mr. Roper’s address is 447 North Broad Street, Philadelphia, and those having the care of steam-boilers cannot do better than address him on the subject. 2 USE AND ABUSE OF THE STEAM-BOILER. The Newark Artisan, Newark, N, J, We have, from time to time, favorably noticed the publica- tions, relating to the steam-engine proper and its collaterals, by Stephen Roper, 447 North Broad Street, Philadelphia, Pa., and published by Messrs. Claxton, Remsen & Haffelfinger of that city. The recent publication, USE AND ABUSE OF THE STEAM- BOILER, meets our most hearty approval, as embodying fully all its title indicates. The work is entirely devoid of abstruse terms, and comes squarely down to the understanding of the ordinarily educated mechanic in so plain a manner as cannot be misunderstood. As we have said of Mr. Roper’s previous publications, we now say of this,—that employers can do them- selves no greater service than placing a copy of this work in the hands of the employé in charge of their engines. North-western Lumberman, Chicago, Ill, As the author of “ Roper’s Hand-Book of the Eeattaitve, ? ‘“‘ Roper’s Hand-Book of Land and Marine Engines,’’ “‘ Roper’s Catechism of High Pressure or Non-Condensing Steam-En- - gines,” and of other valuable contributions to our mechanical literature, Mr. Roper needs no introduction to such of our readers as are interested in steam machinery. Like his former works, the USE AND ABUSE OF THE STEAM-BOILER is emi- nently practical in its character and designed for the use of practical men. ‘Bearing in mind the difficulty which ordinary mechanics experience in endeavoring, as they sometimes do, to extract information from books of a scientific nature, he has used plain, clear language, to convey his meaning instead of ambiguous scientific terms, and where it has been necessary to give mathematical information, has employed simple arith- metical calculations, in lien of abstruse algebraic formule. From an experience with boilers and steam machinery extend- _ ing over a period of thirty years, Mr. Roper has been able to gather an amount of practical knowledge which, combined with that derived from other sources and condensed and arranged 3 USE AND ABUSE OF THE STEAM-BOILER., in the convenient form in which we find it, makes one of the most valuable books for reference and instruction, in this par- ticular department, to be found in the language. It is wide in its scope, and includes besides a full description and explanation of nearly all the different styles of boilers which the genius of the nineteenth century inventor has produced, how best to use and preserve them and their attachments; a large quantity of additional matter in the way of rules for estimating the strength of materials, safe working pressure, horse-power and heating surface of steam-boilers, etc., ete. The tables, which are plen- tifully interspersed throughout the work—and which are fortunately arranged so as to be comprehensible even to those who are not Ph. D.’s —also contain within a small space a vast amount of information which is of practical value to the every- day engineer. It is printed in large, clear type, and bound in morocco, in handy, pocket-book form, and is in all respects a volume which every one interested in steam will be the pi and wiser for having in his possession. National Carbullder, New York City. This is a very compact and comprehensive pocket manual, and is the only book that has been published in this country devoted exclusively to this subject. The various kinds of steam- boilers now in use, comprising stationary, locomotive, fire and marine, are illustrated and described. Rules are given for esti- mating strength of materials, safe working pressure, horse- power, heating surface, ete. Nothing is omitted pertaining to the functions, care, and management of boilers. The yolume is a plain, practical treatise, devoid of scientific technicalities and algebraic formulas, and can be easily understood by the ordi- nary reader. It should be in the hands of every mechanic in charge of steam-boilers. There is a general and analytical index. 4 - USE AND ABUSE OF THE STEAM-BOILER BY STEPHEN ROPER, ENGINEER, Author of ‘Roper’s Catechism of High-Pressure or Non-Condensing Steame Engines,” “ Roper’s Hand-Book of the Locomotive,” “ Roper’s Hand-Book of Land and Marine Engines,” “ Roper’s Hand-Book of Modern Steam Fire-Engines,” “ Roper’s Handy-Book for Engineers,” “ Roper’s Improve- ments in Steam-Engines”, etc., etc, With Kilusteations, ELEVENTH EDITION, REVISED. PHILADELPHIA: EDWARD MEEKS, 1012 Watyvur Srreer, 1890, Entered, according to Act of Congress, in the year 1876, by EDWARD MEEKS, in the Office of the Librarian of Congress at Washington. Prete rere Cree eeererrrrr ees eeee rere ever er eee eee a errerr reer ever rrre rrr recer retirees eee eee 1) = am Oe a> © Roos \QAU TO JAMES M. ALLEN, Eso., PRESIDENT OF THE HARTFORD STEAM-BOILER INSPECTION AND INSURANCE COMPANY, This Volume IS RESPECTFULLY INSCRIBED BY THE AUTHOR, As amark of appreciation of the eminent services which he has rendered humanity by his thorough investigations into the causes of steam-boiler explosions, by means of which they have been stripped of e their apparent mystery and assigned to real causes, ili INTRODUCTION, ‘TT is not the writer’s intention to enter into an elab- orate discussion on the relative merits of the dif- ferent varieties of boilers now in use, nor on the open and unsettled questions connected with steam-boiler engineering, such as the horse-power of boilers, the quantity of grate and heating surface which should constitute the commercial horse-power, the propor- tion of safety-valves to grate and heating surface, or what part of the shell, flues, or tubes of a boiler should be considered heating surface. His object being simply to show what the results gathered from experience prove to be the safest and most durable materials for their manufacture, to show the absolute necessity of good workmanship in their construction, and to call the attention of owners, engineers, and firemen to the evils that limit their usefulness, safety, and longevity. ; The writer’s experience with all classes of boilers extends over a period of thirty years, which enables him to fully understand the kind of information most needed by the men generally found in charge eure Sie ¥ vi INTRODUCTION. of them, and he has tried to convey his meaning in language so plain that it may be understood by any person of ordinary intellect. Of what use are alge- braical formule to men who do not fully understand them? Do we not write and speak to make our- selves understood? If so, why should anything be embodied in a work on the care and management of steam-boilers which persons of the most limited education cannot comprehend? Until quite recently, it was impossible, for persons needing information, to procure a plain, practical treatise on this subject; this arose, perhaps, from the fact, that men who had attained proficiency in this line of business had no taste for devoting their time to writing, and that those whose circumstances enabled them to do so were prevented by a want of that practical knowl- edge which can only be obtained by years of hard work, close study and observation. The great mistake of many writers on the steam- boiler and steam-engine is, that they write too much ; if they would condense and render such explanations as would.come within the comprehension of men of ordinary intelligence, they would do more to diffuse information among the class of men for whom they pretend to write than by writing elaborate treatises, INTRODUCTION, © Vii replete with algebraical formule and purely scien- tific terms, and couched in language incapable of being understood by the very men who most need the information, leaving them to interpret the mean- ing as best they may. What engineers and mechanics generally want is perspicuous and terse language, concise expressions and clear explanations. It is also quite customary for writers on the steam- boiler to regale their readers with accounts of the able researches of Joule, Peclet, Rankine, and others; in the’ field of Thermo-dynamics, which, however edifying to the writers themselves, can be of no value to men having charge of steam-boilers, as not one in one thousand of them, even if they could procure these scientific theories, (which is extremely doubtful, as the researches of Joule and Peclet were never published in the English language,) would be able to decipher or understand them; and Rankine’s works, though quite common, are nevertheless beyond the comprehension of the majority of men in charge of steam-boilers. There is far greater need for the dis- semination of plain, practical, and correct information in regard to the functions of the steam-boiler, its care and management, than of the steam-engine, because the former is more subject to the uncertainties of Vill INTRODUCTION. indiscretion and ignorance than the latter, and in the case of the former, neglect is attended with more serious results. . Rules are given for estimating the strength of materials, safe working pressure, horse-power and heating surface of steam-boilers, the collapsing pres- sure of flues, etc., and also the aggregate strain to which boiler shells and flues are subjected when in use, as a knowledge of the material so extensively employed in the construction of steam-boilers, and the strains to which they are subjected, must be of great value to engineers, whether engaged in the construction of new or in the repairing of old ones. In fact, it has been the main object of the writer, in the preparation of this book, to put in practical shape, for the benefit of engineers and steam-users, the in- formation collected from his own experience, as well as from other reliable sources; and while, in the preparation of the book, it became necessary to dis- cuss the relative merits and peculiarities of a great variety of steam-generators, the writer has endeavored to do so without prejudice, and solely with the view of benefiting the class of persons for whom the book was intended. 8S. R. CONTENTS. For a full reference to the Contents in detail, see Index, page 341. ‘ 5 PAGE ADJUNCTS OF THE STEAM-BOILER . ; ; PLO STrEAM-BOILERS : ; ‘ ? ‘ Rees Ws DESIGN OF STEAM-BOILERS .. , ; : oe ont) ForMs OF STEAM-BOILERS P ‘ ; on OT THE PLAIN CYLINDER BOILER ; ‘ F au 28 THE FLUE BOILER . : J ‘ . F . 28 THE TUBULAR BOILER . ; 5 ; . PRE THE DOUBLE-DECK BOILER . : r ‘ 31 THE DROP-FLUE BOILER. ‘ i . P Sige THE LOCOMOTIVE BOILER : ; , ’ . 83 FIRE-BOX BOILERS . F j ; : A pet TUBULOUS BOILERS . ! ; ‘ : ‘ . oo S1zE OF BOILERS : ‘ . , , rae ¥ 6 SECTIONAL STEAM-BOILERS . ; : 88 MARINE BOILERS . , AL, 49, 46 Table showing the Nimbes of Bidars Feet of Heating Surface to 1 Square Foot of Grate Sur- face in the Boilers of noted Ocean, River, and Ferry-boat Steamers . : ; : é . 47 BOILER-HEADS . ; : F : . “ 8 HO STEAM-DOMES . - ; ‘ P : . . Oa MUD-DRUMS. ‘ 56 W ATER-SPACE AND ee -ROOM IN aay as BOILERS 58 ix x CONTENTS. DIAMETER AND LENGTH OF STEAM-BOILERS AND THICKNESS OF BOILER-PLATE . : : ‘ EVAPORATION IN STEAM-BOILERS . : ; . EVAPORATIVE EFFICIENCY OF STEAM-BOILERS . CLAPP AND JONES’ VERTICAL CIRCULATING TUBU- LAR BOILER 5 : : . ; 1 ; METHODS OF TESTING THE EVAPORATIVE EFFI- CIENCY OF STEAM-BOILERS : : : ; “PROPORTION OF GRATE SURFACE TO HEATING SURFACE. jo +. : ‘ F : ‘ : INTERNAL AND EXTERNAL CORROSION OF STEAM- BOILERS . 3 , 2 ; HG , INTERNAL GROOVING IN STEAM-BOILERS : : SILSBY’S VERTICAL TUBULAR BOILER . , ‘ EXPANSION AND CONTRACTION OF. BOILERS . ‘ ‘-HEATING-SURFACE OF STEAM-BOILERS . ; 4 Rules for finding the Heating-surface of Steam- boilers : ; ? E , : E 5 THE LATTA STEEL COIL-BOILE ‘ 2 ; : HORSE-POWER OF STEAM-BOILERS . ; : A THE MooRHOUSE SAFETY SECTIONAL BOILER : SETTING STEAM-BOILERS . : : ; : : TESTING STEAM-BOILERS . ; ‘ ‘ REPAIRING STEAM-BOILERS . ; ; ; NEGLECT OF STEAM-BOILERS . ‘ : ; ; THE WIEGAND SECTIONAL BOILER. , ‘ ; SAFE WORKING PRESSURE OF STEAM-BOILERS : Table of Safe Internal Pressures for Steel Boilers. Table of Safe Internal. Pressures for Iron Boilers. THE ROGER’s AND BLACK BOILER . , ; é SELECTION OF STEAM-BOILERS. ; i ; ; PULSATION IN STEAM-BOILERS ; ; 4 : PIERCE’S ROTARY TUBULAR BOILER : A : PAGE 59 61 63 69 70 73. 73 78 80 80 83 87 89 92 98 100 . 108 . 107 110 111 115 119 128 129 129 131 133 CONTENTS, LOCATION OF STEAM-BOILERS . ; : THE HARRISON BOILER . : : : ‘ BOILER-FLUES . : : Table of Squares of Thickntes of Ten ane Gar stant Numbers to be used in Auda the Safe External Pressure for Boiler-flues Table of Safe Working External Pressures on Flues 10 Feet long Table of Safe Working Eutenial Beccares on Flues 20 Feet long COLLAPSING PRESSURE OF Wrovenn IRON chee aes FLUES 4 INCH THICK . COLLAPSING PRESSURE OF Wrovdene TRON Boreas FLUES 7°, INCH THICK ' COLLAPSING PRESSURE OF Wrowae? -IRON Borie: FLUES 3 INCH THICK. Rahat PRESSURE OF WrougEe IRON Bonne FLUES 7; INCH THICK ; ‘ ; j THE SHAPLEY BOILER } : ; ‘ BoILeR TUBES . ; ; ‘ é : THE PHLEGER BOILER . ; : Tables of Superficial Areas of External Buibfated of Tubes of Various Lengths, Diameters in Square Feet ; Table of Superficial hiene of Tubes of different Lengths and Diameters from 23 to 3 Inches and from 8 to 20 Feet : ; Srmam- BOILER CONNECTIONS AND Movtenu terra ; GAUGE-COCKS . : ‘ : . STEAM-GAUGES. P , A : y 4 : GLASS WATER-GAUGES ., : ( ‘ " THE BABcock AND WILCOX’S Serra STEAM- BOILER . . . .) . L] e ‘J xii CONTENTS. SAFETY-VALVES : : : : Table showing the Tike of Safety- Walves, { in parts of an Inch at different Pressures : : : Table of Comparison between Experimental Results and Theoretical Formule . RURES SO eras TS AE SR meee tire oh, WITTINGHAM’S ToRuLods BortER. 5 ° 5 FOAMING IN STEAM-BOILERS . é . ‘ P INCRUSTATION IN STEAM-BOILERS . : : ‘ PREVENTION AND REMOVAL OF SCALE IN STEAM- BOILERS . F , : ‘ ; ‘ , STEAM-BOILER EXPLOSIONS . ; : i EXPERIMENTAL BOILER EXPLOSIONS . , ‘ THE Root BoILER . : : i : VAGARIES OF EXPERTS IN REGARD To STEAM- BOILER EXPLOSIONS . " : ‘ ‘ A DEFECTS IN THE CONSTRUCTION OF STEAM-BOILERS. IMPROVEMENTS IN STEAM-BOILERS. ; P Aree THE ALLEN BOILER. : : ; : é : CARE AND MANAGEMENT OF STEAM-BOILERS. ah INSTRUCTIONS FOR FIRING . j , ‘ ‘ DAMPERS . : ( ; ‘ ; : , ; STEAM-BOILER INSPECTION . ; Rules for finding the Quantity of Water whih Boilers and other Cylindrical Vessels are capa- ble of Containing . 5 i : ; EFFECTS OF DIFFERENT KINDS OF Furi ON STEAM- BOILERS . c : ; ‘ é , ; BoILER MATERIALS. ‘ : ; d 4 : STEEL : : s : f ‘ Q ‘ STRENGTH OF IRON BoILER- PLATE. 4 ? i DEFINITIONS AS APPLIED TO BOILERS AND BOILER MATERIALS : : ; : ‘ ; : 277 CONTENTS. PUNCHED AND DRILLED HOLEs FOR BOILER SEAMS. 281 Table showing the Strength of Welded Boiler- plates. ; 3 : . ‘ . 286 PATENT BOILERS Zot THE GALLOWAY BOILER. i's ame STRENGTH OF RIVETED SEAMS . 290 COMPARATIVE STRENGTH OF SINGLE- AND Taine: RIVETED SEAMS, (i291 HAND- AND MACHINE-RIVETING . 298 COUNTER-SUNK RIVETS . 295 RIVETS . 296 Table hie ae irntter ine Pitch of Heats ae different Thicknesses of Plate e297 STRENGTH OF STAYED AND FLAT BOILER Sie las 297 BOILER-STAYS . . 299 STAY-BOLTS . ol CALKING . : . 303 TESTING-MACHINES . . 3808 FEED-WATER HEATERS . . 809 Table showing the Units of Héas eared ie oa. vert One Pound of Water, at the Temperature of 32° Fah., into Steam at different Pressures GRATE-BARS CHIMNEYS. ; Table showing ae Prones Diet vi Height of Chimney for any kind of Fuel of Area of Section of the Chimney . ; SMOKE : ; CONTRIVANCES FOR > dacetaeaa Da iiene AND ECONOMIZING FUEL IN BOILER FURNACES . 2 xiii PAGE . 311 . 314 . 815 . 317 Table showing Heights of Chimneys for Draduoltce certain Rates of Combustion per Square Foot . 318 » 319 321 xiv CONTENTS. Table showing the Actual Extension of Wrought- iron at various Temperatures. : . 824 Table showing the Linear Dilatations of Bislida by Heat . : . 826 Table deduced from ix nenenr erie on Loh Plates for Steam-boilers, by the Franklin Institute, Philadelphia . . 826 Table showing the Readies af Experiments er on different Brands of Boiler Iron at the Stevens Institute of Technology, Hoboken, N. J. . . 827 Table showing the Weight of Cast-iron Balls from 3 to 13 Inches in Diameter. ‘ . 828 Table showing the Weight of Cast-iron Plates per Superficial Foot as per Thickness. . 828 Table showing the Weight of Round-iron fou 4 an Inch to 6 Inches Diameter, One Foot Long. 329 Table showing the Weight of Boiler-plates One Foot Square and from ysth to an Inch Thick . 880 Table showing the Weight of Square Bar-iron from 4 an Inch to 6 Inches Square, One Foot Long . 330 Table showing the Weight of Cast-iron Pipes, One Foot in Length, from } Inch to 14 Inches Thick, and from 3 to 24 Inches Diameter. . 8381 Table showing the Tensile Strength of various Qualities of American and English Cast-iron . 332 Table showing the Tensile Strength of various Qualities of American Wrought-iron. ‘ . 8383 Table showing the Tensile Strength of various Qualities of English Maa: : ; . 834 To PotisH Brass. ‘ iy Meee . 334 CEMENT FOR MAKING STEAM-JOINTS i: REE OBO STEAM-DAMPERS . aa . ; . 339 INDEX gery ; “ f : ; " . 341 LIST OF ILLUSTRATIONS, PAGE ADJUNCTS OF THE STEAM-BOILER . a ee . Le PLAIN CYLINDER BOILER é A ; , 4 28 FLUE-BOILER . : : ; i - ; 3 29 TuBULAR BorueR . : ; z ? ' 3 30 DOUBLE-DECK BOILER . 3 ‘ . : 31 DRoP-FLUE BOILER Lf : : ; : Ca ee LocoMoTIvE BoILER . : ; ¢ : < 33 MARINE BoILERS . , ; ‘ zi “ 42, 46 BorLER-HEADS , ‘ , : ; é ; ye DO STEAM-DOME . ; * ¥ ; é : : ne Mup-pRuM .. : . : 56 VERTICAL TUBULAR BorLers é ‘ pets 68 THe LATTA STEAM-BOILER . : ‘ 90, 91 MooRHOUSE SAFETY SECTIONAL Borner d : 99 WIEGAND SECTIONAL BOILER : ; : : : 112 RoGErR’s AND BuAcK Borer. : : 2 : hes Piprce’s RoTary TUBULAR BOILER . ‘ ; paket: THE HARRISON SECTIONAL BOILER ; } : . 189 THE SHAPLEY BOILER . ‘ . i : : . 154 Tue PHLEGER BoILER . : , ; : ; . 159 (GGAUGE-COCKS : : , ; E , - . 168 STHAM-GAUGES ‘ : ; - . ; A . 170 GuAss WATER-GAUGES £ 173 Taw BABcocK AND WILCOX’s SECTIONAL STEAM-BOILER 175 THE SAFETY-VALVE ‘ : : ; . 176 WITTINGHAM’s TUBULOUS Boruer. N 189 EXPLODED BoILER OF THE FERRY-BOAT “ WESTFIELD. ” 208 Exprniopep BorLerR oF THE ‘“ CHARLES WILLARD.” 222. - THE Root Borer . se l6 DIAGRAM ILLUSTRATING DEFECTS | IN STEAM-BOILERS . 231 THE ALLEN BoILER ; ; : : F : 205 RIVETED SEAMS. , F : } ; ; . 293 CALKING ; : j , : : : . 804 CHIMNEYS . é ; - . ; ; . 816 AUTOMATIC STEAM-DAMPER : } 2 ; : $2009 ADJUNCTS OF THE STEAM-BOiLER. USE AND ABUSE OF THE STEAM-BOILER. STEAM-BOILERS. STEAM-BOILER may be defined as a close vessel, in which steam is generated. It may assume an endless variety of forms, and can be con- structed of various materials. Since the introduction of steam as a motive power, a great variety of boilers has been designed, tried, and abandoned; while many others, having little or no merit as steam-generators, have their advocates, and are still continued in use. Under such circum- 2* B 17 18 USE AND ABUSE OF stances, it is not surprising that quite a variety of opinions are held on the subject. This difference of opinion relates not only to the form of boiler best adapted to supply the greatest quantity of steam with the least expenditure of fuel, but also to the dimen- sions or capacity suitable for an engine of a given number of horse-power; and while great improve- ments have been made in the manufacture of boiler materials within the past fifteen years, yet the number of inferior steam-boilers seems to increase rather than diminish. It would be difficult to assign any reasonable cause for this, except that, of late years, nearly the whole attention of theoretical and mechanical engineers has been directed to the improvement and perfection of the steam-engine, and practical engineers, following the example set by the leaders, devote their energies to the same object. This is to be regretted, as the construction and application of the steam-boiler, like the steam-engine, is deserving of the most thorough and scientific study, as on the basis of its employment rest some of the most important interests of civilization. Until quite recently, the idea was very generally entertained that the purely mechanical skill required to enable a person to join together pieces of metal, and thereby form a steam-tight and water-tight vessel of given dimension, to be used for the generation of steam ta work an engine, was all that was needed; experience has shown, however, that this is but a small portion THE STEAM-BOILER, 19 of the knowledge that should be possessed by persons who turn their attention to the design and construc- tion of steam-boilers, as the knowledge wanted for this end is of a scientific as well as of a mechanical nature. As the boiler is the source of power, and the place where the power to be applied is first generated, and also the source from which the most dangerous con- sequences may arise from neglect or ignorance, it should attract the special attention of the designing and mechanical engineer, as it is well known that from the hour it is set to work, it is acted upon by destroying forces, more or less uncontrollable in their work of destruction. These forces may be distin- guished as chemical and mechanical. In most cases they operate independently, though they are fre- quently found acting conjointly in bringing about the destruction of the boiler, which will be more or less rapid according to circumstances of design, con- struction, quality of material, management, etc. The causes which most affect the integrity of boilers and limit their usefulness, are either inherent in the material or due to a want of skill in their construction and management; they may be enumer- ated as follows: First, inferior material; second, slag, sand, or cinders being rolled into the iron; third, want of lamination in the sheets; fourth, the overstretching of the fibre of the plate on one side and puckering on 20 USE AND ABUSE OF the other in the process of rolling, to form the circle for the shell of a boiler; fifth, injuries done the plate in the process of punching; szath, damage induced by the use of the drift-pin; seventh, carelessness in rolling the sheets to form the shell, as a result of which the reams, instead of fitting each other exactly, have in many instances to be drawn together by bolts, which aggravates the evils of expansion and contraction when the boiler is in use; eighth, injury done the plates by a want of skill in the use of the hammer in the process of hand-riveting; ninth, damage done in the process of calking. Other causes of deterioration are unequal expan- sion and contraction, resulting from a want of skill in setting; grooving in the vicinity of the seams ; internal and external corrosion; blowing out the © boiler when under a high pressure and filling it again with cold water when hot; allowing the fire to burn too rapidly after starting, when the boiler is cold; ignorance of the use of the pick in the process of - scaling and cleaning ; incapacity of the safety-valve ; excessive firing; urging or taxing the boiler beyond its safe and easy working capacity; allowing the water to become low and thus causing undue expan- sion; deposits of scale accumulating on the parts exposed to the direct action of the fire, thereby burning or crystallizing the sheets or shell; wasting of the material by leakage and corrosion ; bad design and construction of the different parts; inferior THE STEAM-BOILER. 21 workmanship and ignorance in the care and manage- ment. All these tend with unerring certainty to limit the age and safety of steam-boilers. On account of want of skill on the part of the designer and avarice on the part of the manufac- turer, or, perhaps, both reasons, boilers are some- times so constructed as to bring a riveted seam directly over the fire, the result of which is, that in consequence of one lap covering the other the water is prevented from getting to the one nearest the fire, for which reason the lap nearest the fire becomes hotter and expands to a much greater extent than any other part of the plate; and its constant un- ~ equal expansion and contraction, as the boiler be- comes alternately hot and cold, inevitably results ina crack. Such blunders are aggravated by the scale and sediment being retained on the inside, between the heads of the rivets, which can never be properly removed in cleaning. The tendency of manufacturers to work boilers beyond their capacity, especially when business is driving, is too great in this country; and no doubt many boiler explosions may be attributed to this cause. Boilers are bought adapted to the wants of the manufactory at the time, but, as business in- creases, machinery is added to supply the demand for goods, until the engine is overtasked, the boiler strained and rendered positively dangerous. Then, again, it not unfrequently occurs that engines in 22- USE AND ABUSE OF manufactories are taken out and replaced by those of increased power, while the boilers used with the old engine are retained in place, with more or less cleaning and patching, as the case may require. Now, it is evident to any practical mind that boilers constructed for a twenty-horse power engine are ill adapted to an engine of forty-horse power, more especially if those boilers have been used for a number of years. In order to supply sufficient steam for the new engine, with a cylinder of in- creased capacity, the boiler must be worked beyond its safe working pressure, consequently excessive heating and pressure greatly weaken it and endan- ger the lives of those employed in the vicinity. The danger and impracticability of using boilers with too limited steam-room may be explained thus: Suppose the entire steam-room in a boiler to be six cubic feet, and the contents of the cylinder which it supplies to be two cubic feet; then, at each stroke of the piston, one-third of all the steam in the boilers is discharged, and consequently one-third of the pressure on the surface of the water before that stroke is relieved; hence it will be seen that exces- sive fires must be kept up in order to generate steam of sufficiently high temperature and pressure to supply the demand. The result is that the boilers are strained and burned. Such economy in boiler: power is exceedingly expensive in fuel, to say nothing of the danger. Excessive firing distorts THE STEAM-BOILER. 23 the fire-sheets, causing leakage, undue and unequal expansion and contraction, fractures, and the conse- quent evils arising from external corrosion. Exces- sive pressure arises generally from a desire on the part of the steam-user to make a boiler do double the work for which it was originally intended. A boiler that is constructed to work safely at from fifty to sixty pounds was never intended to run at eighty and ninety pounds; more especially if it had been in use for several years. Boilers deteriorated by age should have their pressure decreased, rather than increased. One ‘of the first things that should be done in manufacturing establishments would be to provide sufficient boiler-power, and, in order to do this, the work to be done ought to be accurately calculated and the engine and boilers adapted to the results of this calculation. Steam-users themselves are fre- quently to blame for the annoyances and dangers arising from unsafe boilers and those of insufficient capacity. For motives of false economy they are too easily swayed in favor of the cheaper article simply because it is cheap, when they should con- sider they are purchasing an article which, of almost all others, should be made in the most thorough manner and of the best material. In view of the fearful explosions that occur from time to time, every steam-user should secure for his use the best and the safest. The object of a few dollars, as 24 USE AND ABUSE OF between the work of a good, responsible maker and that of an irresponsible one, should not for one moment be entertained. It is very bad policy for steam-users to advertise for estimates for steam-boilers, or to inform all the boiler-makers in the town or city that a boiler or boilers to supply steam for an engine of a certain size is needed, because in this way steam-users fre- quently find themselves in the hands of needy per- sons, who, in their anxiety to get an order, will sometimes ask less for a boiler than they can actu- ally make it for; consequently, they have to cheat in the material, in the workmanship, in the heating- surface, and in the fittings. As a result the boiler is not only a continual source of annoyance, but, in many instances, an actual source of danger. The most prudent course, and in fact the only one that may be expected to give satisfaction, is to contract with some responsible manufacturer that has an established reputation for honesty, capability, and fair dealing, and who will not allow himself to be brought in competition with irresponsible parties for the purpose of selling a boiler. There are thousands of boilers designed, con- structed, and set up in such a manner as to render it utterly impossible to examine, clean, or repair them. Generally in such cases, in consequence of imperfect circulation, the water is expelled from the surface of the iron at the points where the extreme heat from THE STEAM-BOILER 25 the furnace impinges, and, as a result, the plates become overheated and bulge outward, which aggra- vates the evil, as the hollow formed by the bulge becomes a receptacle for scale and sediment. By continued overheating the parts become crystallized, and either crack or blister; this, if not attended to and remedied, will eventually end in the destruction of the boiler. Many boilers, to all appearance well made and of good material, give considerable trouble by leakage and fracture, owing to the severe strains of unequal expansion and contraction induced by their rigid construction, the result of a want of skill in the original design. DESIGN OF STEAM-BOILERS. it has become a general assertion on the part of writers on the steam-boiler that the most important object to be attained in its design and arrangement is thorough combustion of the fuel. This is only partially true, as there are other conditions equally important, among which are strength, durability, safety, economy, and adaptability to the particular circumstances under which it is to be used. How- ever complete the combustion may be, unless its products can be easily and rapidly transferred to the water, and unless the means of escape of the steam from the surfaces on which it is generated is easy and direct, the boiler will fail to produce satis- 3 26 USE AND ABUSE OF factory results either in point of durability or econ- omy of fuel. Strength means the power to sustain the internal pressure to which the boiler may be subjected in ordinary use, and under careful and intelligent man- agement. To secure durability, the material must be capable of resisting the chemical action of the minerals contained in the water, and the boiler ought to be designed so as to produce the least strain under the highest state of expansion to which it may be subjected,— be so constructed that all the parts will be subjected to an equal expansion, con- traction, push, pull and strain, and be intelligently and thoroughly cared for after being put in use. These objects, however, can only be obtained by the aid of a knowledge of the principles of mechanics, the strength and resistance of materials, the laws of expansion and contraction, the action of heat on bodies, ete. The economy of a steam-boiler is influ- enced by the following conditions: cost and quantity of the material, design, character of the workman- ship employed in its construction, space occupied, capability of the material to resist the chemical action of the ingredients contained in the water, the facilities it affords for the transmission of the heat from the furnace to the water, ete. The safety of any structure depends on the designer’s knowledge of the principles of mechanics, the resistance of materials, and the action of bodies as influenced by THE STEAM-BOILER. 27 the elements 'to which they are exposed; and in the case of steam-boilers the safety depends on the judg- ment of the designer, the quality of the material, the character of the workmanship, and the skill employed in the management. Safety is said to be incompatible with economy, but this is undoubtedly a mistake, as an intelligent economy includes per- manence and seeks durability. Adaptability to the peculiar purposes for which they are to be used is one of the first objects to be sought for in the design and construction of any class of machines, vessels, or instruments, and it is undoubtedly this that gave rise to: the great variety of designs, forms, and modifications of steam-boilers in use at the present day, which are, with very few exceptions, the result of thought, study, investigation, and experiment. FORMS OF STEAM-BOILERS. According to the well-known law of kydrostatics, the pressure of steam in a close cylindrical vessel is ‘exerted equally in all directions. In acting against the circumference of a cylinder, the pressure must therefore be regarded as radiating from the axis, and exerting a uniform tensional strain throughout the enclosing material. The cylindrical form, whether used for the shell of a boiler in which it is subjected to internal pressures, or for the flues through which the gases escape, or for tubes for the 28 USE AND ABUSE OF circulation of the water, is the form best adapted for strength, permanence of shape, and cheapness of construction ; as flat surfaces, when exposed to high pressures, are positively dangerous, and whenever any departure from the circular form has been at- tempted, the result has been a failure. THE PLAIN CYLINDER BOILER. The plain cylinder boiler, shown on this page, is one of the earliest forms of steam-generators, as well as one of the most simple in construction, and, until quite recently, one of the most extensively used, but it is fast passing out of use, except in localities where economy of fuel is a secondary object. Its advantages were lightness, moderate first cost, and that it afforded better facilities for cleaning, repair- ing, or the renewal of any of its parts, than any other type of boiler. It also possessed peculiar advantages for rolling-mill and blast-furnace pur- poses, as it required little care, and was least danger- ous on account of the great body of water it con- THE STEAM-BOILER. 29 tained. Its disadvantages were its great length, es- pecially in locations where space was of great value; its waste of fuel, arising from its limited heating surface; and the great body of useless water it con- tained, which had to be heated every time the boile» cooled. THE FLUE BOILER. The flue boiler, illustrated above, is a modifi- cation of the plain cylinder, and is characterized by an arrangement of one or more flues, generally two, though in some cases three or even five, running longitudinally within the shell through which the smoke and gases from the furnace pass to the chimney. With the same length and diameter, the heating surface is much greater than in the cylinder boiler, consequently it occupies less space, which is an object of great importance in many instances. But it has the disadvantages of extra weight, in- creased first cost, and that it is more difficult. to 3%* 30 USE AND ABUSE OF clean or repair. It also requires more care on account of the liability of the flues to become over- heated and collapse, in case the regular supply of water should be neglected. Like the cylinder, it is fast being replaced by other forms. THE TUBULAR BOILER. The tubular boiler, a cut of which may be seen on this page, is similar to the flue, except that, instead of large return flues, small tubes are used for the escape of the smoke and gases from the furnace to the chimney, and the transmission of the heat to the water. This boiler, with its various modifications, is probably in more general use for stationary, locomo- tive, and marine purposes, than any other form. Its introduction and employment as a steam-generator formed the basis for some of the most important im- provements heretofore made in railroad and marine steam-engineering. THE STEAM-BOILER. 31 The tubular boiler possesses many advantages, in an economical point of view, over either the cylinder or flue, as it occupies less space, and requires less fuel to evaporate a certain quantity of water in a given time, and in consequence of the small diameters of the tubes, their liability to collapse is entirely obvi- ated. Its great disadvantages are that it is impossible to clean, and in many instances very difficult to re- pair. It requires equally as much attention as the flue boiler, and more than the plain cylinder. - THE DOUBLE-DECK BOILER. The double-deck boiler, a cut of which may be seen on this page, is a combination of the plain cylinder and tubular. It consists of a tubular and cylinder boiler, connected together by necks. This kind of boiler presents an immense amount of heating surface, as the heat and gases pass under the tubular boiler, 32 USE AND ABUSE OF return through the tube, and re-return between the tubular and cylinder shells before passing into the chimney. It requires less attention than either the flue or tubular boiler, as in consequence of the tubu- lar section being continually full of water, and the upper section or cylinder forming the steam-dome, there is very little danger of the tubes becoming stripped. Though it requires considerable room between joints, it occupies less floor space than the tubular. Its disadvantages are its extra weight and first cost, and that it is very difficult to clean or repair. THE DROP-FLUE BOILER. Boilers of this class are generally of a large diam- eter and are internally fired, the furnace being in the front end of the boiler, the smoke and heated gases escaping through the upper flues, returning through the middle flues, and escaping to the chimney through THE STEAM-BOILER, 33 the lower tier. They are very efficient, and are fre- quently employed for marine purposes, but are liable to crack and become leaky, in consequence of the unequal expansion and contraction to which the sheets are exposed at the points where the flues return. THE LOCOMOTIVE BOILER. The locomotive boiler, a cut of which is shown on this page, though not in very general use for stationary purposes, when well proportioned for its work, is very economical, as it occupies but little space, presents an immense amount of heating sur- face, steams very rapidly, and, when well constructed, is compact and powerful. This is owing to the fact that the fuel is burned in a metallic fire-box, sur- rounded by a water-space which absorbs the heat that would otherwise be lost in heating the walls of C 84 USE AND ABUSE OF a brick furnace, and that the space between tlie grate-bars and crown-sheet is higher than could be obtained in any other design or form of boiler. This is very favorable to combustion. Another advantage is, that the tubes in such boilers are generally of small diameter and more numerous, which of itself is a great advantage, as small boiler-tubes are capable of producing more satisfactory results than large ones, as they not only increase the amount of heating surface, but at the same time can be made of thiyner material. This admits of the heat being conducted more rapidly to the water than if they were large and necessarily thicker. ; FIRE-BOX BOILERS. Fire-box boilers are that class of boilers in which the fuel is consumed in a metal instead of a brick furnace. It includes all locomotives, nearly all marine, and a great many boilers used for stationzry purposes; in fact, all internally-fired boilers may be said to be fire-box boilers. A wide difference of opinion among engineers exists in regard to the economy of fire-box boilers; as, while all agree that the fire-box increases the weight and first cost, some claim that more water can be evaporated to each pound of coal in a fire-box boiler than can be done in a brick furnace, as, in consequence of a more ex- tended metallic surface to absorb the heat from the THE STEAM-BOILER. 85 fuel, more is utilized, and, consequently, less lost: while, on the other hand, it is asserted that the fire- box, though possessing advantages in point of con- venience, has none in point of economy, as, if the fire-box was cut away from any boiler, and the shell set up in brick, it would evaporate as many pounds of water to a pound of coal as when it was connected with the fire-box. Besides, the fire-box is likely to corrode, which induces leakage and neces- sitates repairs. TUBULOUS BOILERS. This class of boilers is in very extensive use as steam generators, and, unlike the tubular, they have no shell. In the tubular boiler the tubes serve to convey the flame and heated gases from the fire, and the expansive force of the steam ‘is controlled by the shell as well as by the tubes, the former sustaining an internal pressure, which has a tendency to rupture it, while the external pressure on the tubes has the effect of causing them to flatten and collapse. In the tubulous boiler, on the other hand, there is no shell, properly so called, and the tubes being filled with hot water and steam sustain an internal pressure only, rendering them safer, particularly if the tubes be of small diameter, as it is well known that a tube of a moderate thickness of metal is capable of withstand- ing with safety a pressure which would utterly de- stroy a boiler of ordinary size. MILIARITY with Steam Machinery, more especially with Boilers, is apt to beget a confidence in the ignorant which is not founded on a knowledge of the dangers by which they are continually surrounded ; while contact with Steam, and a thorough elementary knowledge of its constituents, theory, and action, only incline the intelli- sent Engineer and Fireman to be more cau- tious and energetic in the discharge of rats duties. 36 THE STEAM-BOILER. SF SIZE OF BOILERS. It is generally understood that the larger a steam- boiler is for the work to be done the more economi- cal it will be of fuel, because the combustion is slower, and consequently more perfect, and the flames and smoke are thus in contact with the heated surface a longer time and therefore impart more of their heat to the water, and that—the water capacity of a large boiler being greater than that of a smali one—there is more hot water stored up for use when the maximum power of the engines must he exercised, for which reason the fire need not be forced so much as it would be if it were necessary to generate all the steam consumed at such times as fast as it is used. But it must not be inferred from this that boilers entirely too large for the services they have to perform are economical, as an extra large boiler contains a great body of water and requires an extra quantity of fuel to get up steam every time it is allowed to cool down. [t is not unusual to find manufacturers of steam- boilers recommending a thirty-, or even a forty-horse power boiler for the purpose of supplying steam to a twenty-horse power engine. This is very doubtful economy, as an extra diameter.and length of boiler necessitates extra strength of material, which in- duces extra weight and first cost, and an increased gonsumption of fuel. A. steam-boiler, like any other 4 38 USE AND ABUSE OF machine, should be proportioned to the purposes for which it is intended, and its application to that particular purpose should be the result of mature deliberation, and be based upon sound calculation, and not on custom, hearsay, or any other vagaries that may be popular regarding such things. It is also quite common for small boilers to be replaced with large ones for the purpose of furnish- ing an extra quantity of steam, while, perhaps, the same sized grate-bars, same area of flue, and same chimney are used. Such arrangements are generally influenced either by ignorance or avarice, or perhaps by both, and are sure to give rise to dissatisfaction between the boiler-maker and purchaser. Before purchasing a boiler, it is necessary to know the maximum quantity of steam that will be needed, the quality of the fuel, and the character of the draft, etc. These three things intelligently con- sidered and decided upon, the heating and grate surface can be proportioned accordingly, after which, if the management be careful and intelligent, there can be no reason why the boiler should not give satisfaction. SECTIONAL STEAM-BOILERS, Sectional boilers consist, essentially, of a system of tubes, so arranged that a continuous circulation of the water is maintained through the tubes from THE STEAM-BOILER. 39 the mechanical action arising from some portions of the tubes being maintained at a higher temperature than others, the heated and lighter water ascending and the cooler and heavier water descending. The shell is dispensed with, and the heat applied directly by both radiation and contact to the exterior sur- faces of the tubes. The idea of sectional steam- boilers is claimed to have originated with Jacob Perkins, about the year 1830, and since that time a great variety of designs and constructions of that class of steam-generators has been tried, and nearly all abandoned. This arose partly from a want of knowledge of the requirements of a steam- boiler on the part of their designers, a want of skill in their construction, as well as from a want of proper tools for their adjustment. The claim which opened the way for the introduc- tion of sectional boilers, and one on which their inventors and advocates have laid so much stress, namely, that they were non-explosive, and that a tube, or number of tubes, or even a section, might explode and do but trifling damage, has not held good, at least in all cases, as the accidents at Hoopes & Townsend’s and at Troth & Gordon’s, in Phila- delphia, show, several men having lost their lives in both eases; in one, by the explosion of a section, and in the other by the explosion of the whole boiler. Why, in the face of these facts, such boilers should claim to be non-explosive, or safer than ordinary 40 USE AND ABUSE OF or wrought-iron boilers, is difficult to see. In their construction large quantities of cast-iron are em- ployed, and, to be of equal strength with the wrought-iron, it must of necessity be a great deal thicker. Now, as it is well known that the thin part of steam-boilers expands more rapidly than the thick, and that the limit of the expansion of the two metals is different, it is plain that some parts of sectional boilers must be subjected to an enormous strain, while the strain on other parts will be only that due to the pressure. Most sectional boilers have attached to them a wrought-iron steam-drum, which, except for its smaller diameter, possesses all the dangers of the ordinary wrought-iron boiler; and if this drum is constructed of iron of thinner gauge, or is imperfectly made, the liability to accidents is the same as in the case of the wrought-iron boiler. Besides, most sec- tional boilers are difficult, if not impossible, to clean ; their first cost is more than that of the ordinary cylinder, flue, or tubular, while their evaporative powers are, with very few exceptions, less, and it is generally admitted that they are slow steamers. Though they may occupy less ground space than the ordinary form of steam-boilers, they generally require more room between floor and ceiling, while nothing is known of their durability or longevity. Many of the sectional boilers now in use embody in their designs nearly all the bad points of the old-fashioned THE STEAM-BOILER. 41 wrought-iron boilers, without embracing any of the good ones. Another great disadvantage inherent in nearly all sectional boilers, and one which entails a good deal of annoyance, and incurs a certain amount of danger, is the great variation in pressure and rapid fluctua- tion in the water level, whenever they are worked up to their full capacity. That any of this class of boilers now in use will be able to supersede (as was once claimed by their inventors) the ordinary forms of wrought-iron cylindrical boilers, seems very im- probable; nor is it at all likely that they will ever be able, in point of durability, efficiency, or economy, to successfully compete with them ; still, some recent forms of sectional steam-boilers are creating very favorable impressions. MARINE BOILERS. There is now, as there always has been, a great diversity of opinion among engineers in regard to the true principles upon which to design a marine boiler which will produce the greatest effect with the least stowage, first cost, subsequent labor, and fuel. Ex- perience has shown that the best that can be done, is to determine which of these considerations should have the least weight, and as a guide, look to practice rather than any assumed theoretical principles. For land purposes, there is hardly any limit to the size 4* USE AND ABUSE OF 42 iy Li PATAAIOONNTY TOM eo — ‘Y3TIOG YVINEGAL ANIGVW THE STEAM-BOILER. 43 or weight of a boiler except first cost. It is easy, therefore, to design and construct one with sufficient heating surface, water-space, and steam-room. But in designing a marine boiler the case is quite different, as the designer is restricted both in room and weight ; for if the vessel be occupied or loaded down with boilers, it detracts from the room and capacity that should be devoted to other purposes. Marine boilers are of necessity either flue or tubu- lar, since the flame must be within the shell of the boiler; but in this arrangement they are almost as various as the makers. The large flue is preferable because less liable to choke with soot, ashes, cinders. or salt which may come from leakage. But in situ- ations which restrict length, height, and width of boiler, the only method of producing in a flue boiler such extent of fire surface as will extract all the heat capable of being used to advantage in generating steam, is to reduce the size and multiply the number of flues. The most ordinary forms of marine boilers are the horizontal and vertical; and, so far as effi- ciency is concerned, there does not appear to be any great difference between them, where equal surfaces are presented to the action of the fire; but there are many things, particularly in sea-going steamers, to be considered, and for them that boiler is the best which gives equal effect, occupies least space, and affords the best facilities for cleaning and repairs. A certain proportion between the area of the grate 44 USE AND ABUSE OF and the total heating surface has been found pro- ductive of the best results, with a given description of fuel; but any alteration in the quality of the fuel used will be found to affect this result materially. Consequently, no general rule can be laid down for marine boilers that will answer for all kinds of fuel ; nor is it at all likely that any one form will ever fulfil all the varied conditions under which such boilers may be placed. A consideration of great importance in the construction of marine boilers. is their capacity to contain water and steam. ‘This, of course, depends upon the size of the boiler and the proportion of space occupied by flues or tubes, as, if the space within it be nearly filled with flues, there can be but little room left for water. In fixing on the proper capacity of the water-space of a marine boiler, there are not such peculiar diffi- culties as in the case of the steam-chamber, and any one at.a first view would say, as many do without suf- ficient consideration, that there cannot be too little water, provided the boiler is filled to the proper height; for it is quite obvious the smaller the quan- tity of water the less will be the expenditure of the fuel during the first getting up of the steam after each stoppage of the engine. It is, however, not the “getting up” the steam, but the keeping it up, that ought to be considered of most consequence. It isa prevailing opinion that, after steam is once got up, there is no material difference between keeping a THE STEAM-BOILER. 48 large quantity of water boiling and a small quantity, provided the escape of heat is prevented by sufhi- ciently clothing the boiler with non-conducting sub- stances; but on this subject engineers differ. Why ractical men should differ in opinion on so plain a matter is unaccountable. The quantity of water carried must exceed that of the evaporation in a given time, in order that the supply of feed-water may not greatly reduce the temperature of the water in the boiler and check the formation of steam. There must in all cases bea sufficient height of water in the boiler to prevent the flues or crown-sheet from becoming bare in case the supply of feed-water be neglected or the vessel pitches in a rough sea. When marine boilers are so constructed that steam cannot be taken off above the level of the water without danger of working water into the steam-cylinder, it becomes necessary to resort to the expedient of attaching a steam-dome to the boiler. This steam-dome is constructed either inside or around the smoke-pipe, and, though not adding much to the cubic capacity of the steam-room, has the effect of superheating the steam, or imparting to it an extra heat, which greatly increases its ex- pansive force, and renders it less liable to condense in the passages between the boiler and the cylinder. THE STEAM-BOILER. 47 TABLE SHOWING THE NUMBER OF SQUARE FEET OF HEATING SUR- FACE TO ONE SQUARE FOOT OF GRATE SURFACE IN THE BOILERS OF NOTED OCEAN, RIVER, AND FERRY-BOAT STEAMERS. | Number of sq. feet of heat- NAME OF STEAMER. ten eye of grate sur- face. | Powhatan, Wee Nate. teas ean een es ak 22.3 Susquehannd, 68 ee. nce.coccedeane Bip Pea 25. Mississippi, iy By eS oS Brera ey rier 18.6 San Jacinto, Bek iets oan 5 ni'y San ees 27. Saranac, DE REA coos So dete nicatiiee ai Stamens aa 27.25 Princeton, TOU aces an sean eatin 22. Michigan, RPE Mien dre aha ou ose Rea 19.75 Vixen, CRE ane wetneeia ee 16. Massachusetts, “ “ ...... Ws gtaeeis ts 33.6 Georgia, Merchant Steamer............. 22.25 Washington, ie <6) SRM 23.5 United States, ty 5 aR Rces., 21.9 Northerner, re 4, tee Sage aig on 24.9 Falcon, 3 Aenea ce het 20.8 Philadelphia, ¢ ee th ov eae 21. Republic, My air 3 reece aura: | Ohio a ene ek eee 22.25 Hermann, We Nh fee 30.6 Cherokee, o Sr ea daectcege tec): hy ick Union, ve sige + pe 66.4 Constitution, oe Ws eee Vesey 34.5 Golden Gate, od ee ik ee 32.8 Monumental City, “ CSET aah Ab an 31.4 El Dorado, he ER Maen ya sas 26.8 City of Pittsburg, + Oe tabae's sollaeiy gO Pioneer, Sg ge Ae ee ames 2S Albatross, °) Es veiecehopi. OeOeO Osprey, Spates hecsesven: fe ae4. Humboldt, a eR bert. can tive beet 19.6 Franklin, Ny sti Leagbeien 28.4 48 USE AND ABUSE, ETO, TA BL E..— Continued. | Number of sq. feet of heat- NAME OF STEAMER. Pel Cheer of grate sur- face. Arctic, Merchant Steamer............-s000- 33.25 | Baltic, am AN NAAN tae oe age ee 33.25 Pacific, cs Att Wenteey Wasa Wie sees 33.25 Atlantic, x9 CHE ascGuach oonaewss 33.25 May Flower, 4 Ce eahawe hen bin cane 31.71 Empire State, “ eee eA eye tee 24.5 America, x TOPOMY Meine. Soins se Soeeeee a 32.25 Knoxville, i Tit thusasidew en tputenss 63.1 North America, River Steamer..........sscseeee 22.3 South America, iy Scat abs nl-s «ntewesteg eee 24.9 Oregon, = PeiE it iaaednicas ekeameret 31.3 Alida, Pe Mar tsanevae tenane cee 27.9 Niagara, Ny BAT Pama Are ir, Aerts 27. Joseph Belknap, “ Huse: ea'slbaiew's eee epeh ai 27.9 Mountaineer, a Ed disse chloe aiee SeaeeeS 32. New World, “ rt Ve Ns hie ae 25.17 Traveller, f rah Wain WADE een cae eee 21.3 Isaac Newton, . Ae AK ogelan ld tian hens ee 28.2 Roger Williams, “ PAR Mtvoneniewapae seek 19.2 Thomas Powell, “ re ts she ktet teauer pate 25.5 Armenia, i ite Ee ace reer eed 24.5 America, ¥ ph eae ey red PE 26. Bay State, e nM eset nescaee wads 29.3 Empire State, ik Ay? yA Ae pene 25. Baltimore, ¥ ewimeeat catise subaeess 42.37 J. M. White, Western river Steamer............ 26. Rescue, Shera ch tek ade ynoneheWissabarteet 28. Anglo-Saxon, “ Merchant, Ferry-boat Seneca, Hg Onalaska, ‘i John Fitch, 4: A MOPAR biscestucnsaciencssoetees steer eee We Y regard steam as an incomprehen- sible mystery ; and although they may employ tt as a power to accomplish work, know little of its character or capabilities. Steam may be managed .by common sense rules as well as any other power; but if the laws which regulate its use are violated, it reports itself, and often in louder tones. than ts pleasant. | 5 D 49 50 USE AND ABUSE OF BOILER-HEADS. Flat Head turned Outward, There are two forms of boiler-heads in general use, and four ways in which they are secured to the shell of the boiler. These are — first, the flat head turned outward; second, the flat head turned in- © ward; third, the arched head turned outward; fourth, the arched head turned inward. Consider- ing the two facts, first, that, with a given amount of material, arched forms are stronger than flat ones, and, second, that cast-irou resists compressive better than tensile strains, it plainly appears that the first plan mentioned above is the weakest, and the fourth plan the strongest, mode in which a cast-iron head can be used. It is also true that either form of head is stronger when turned inward than outward. The correctness of these statements, in so far as the strength of the head is concerned, cannot be gain- said; but there are other considerations besides strength which determine the form of boiler-heads. The first to be considered is the arched head turned inward; the strongest plan. It will be THE STEAM-BOILER. 51 noticed that if the head is made of uniform thick- ness, with a curve at the spring-line of the arch, to secure a sound casting between the head and the sheet, an acute angular space is left, liable to fill up with sediment and harden into scale by the action Arched Head turned Inward, of the fire, which is usually severe at this part of the boiler. Experience has shown that the boiler-plates at this point have corroded and burnt out very rapidly with the heads made and inserted in this manner, though the action of the sediment may be prevented by squaring up the head to a right angle with the sheet; but this renders the plate liable to over-heating, from the excessive quantity of cast-iron in contact with it just over the fire. This latter difficulty may, to a certain extent, be overcome by setting the boiler far enough ahead in the front to protect the mass of iron in the head from the severe action of the fire. There are other objections to inserting heads in this manner, such as loss of capacity, etc., resulting from the great space occu- WAIVERSITY OF (ELINGES 52 USE AND ABUSE OF pied by the head in the shell. Now, by adding one- fourth more metal, and distributing it evenly in thickness all over, and giving the head an arched form, it can be turned outward, possess all the re- quirements of strength needed for safety, and avoid the objectionable features of the concave head. The flat head turned outward possesses more objectionable features than any other form, as it is the worst disposition which can be made of metal to withstand internal elastic pressure, as the tendency of the force within a boiler is to cause the flat end Arched Head turned Qutward. to bulge outward, and assume the spherical form. This brings a severe strain upon the point of least resistance, as shown in the cut on page 90, and also upon the rivets which join the head to the shell. Whether boiler-heads be turned inward or outward, it is evident that they must possess strength equal at least to that of the metal of the sheet across the transverse rows of rivet-holes, as the section of metal, after punching, is the measure of strength in any boiler without stays. While we may assume that THE STEAM-BOILER. 53 the head loses the same amount of metal by the rivet-holes, proportional to its thickness, as the sheet does to which it is secured, whatever be the size or number of rivets, we have but to consider, in the comparison of strength, the ratio of thickness of head and sheet and the tensile strength of each material. Wrought-iron heads of the flat, arched, and egg-shaped forms are now very generally used, on account of their great tensile strength, lightness, and the facilities they afford for bracing; more par- ticularly in boilers of a large diameter. -—f ee ae eee eee | SE cas SS STEAM-DOMES. The advantages claimed to be derived from the steam-dome are, that it acts as a steam reservoir and also an anti-primer, in consequence of being further 5* 54 USE AND ABUSE OF removed from the water than any other part of the boiler, which is true to a certain extent; but, as re- gards its advantages as a steam reservoir, it can easily be shown that an ordinary sized steam-dome adds very little to the steam-room of a boiler, For instance, a boiler 48 inches in diameter and 20 feet long would contain 251 cubic feet of space; if we take three-fourths of that as water-space, we will have 1éft about 63 cubic feet for steam-room. Now suppose we take a steam-dome 24 inches in diameter and 2 feet high, we gain only 6 cubic feet of space, the steam from which would fill the cylinder of an engine 12 inches in diameter and 24-inch stroke five times, even if worked expansively. Now, with respect to its advantages as an anti- primer, it appears to be taken for granted that the higher the point at which the steam is taken from the boiler, the drier it is likely to be; but the cool- ing effect on the steam, by domes of large diameter exposed to the atmosphere, seems to be entirely lost sight of, as it is well known that when an engine is at work, the steam rushes into and through the dome with great velocity, and in its passage is liable not only to take with it a great quantity of water, but have its temperature lowered by coming in contact with so much surface exposed to the action of the atmosphere. It frequently happens that the steam taken from a dome is more wet than that in any other part of the boiler. THE STEAM-BOILER. 339) The reservoir of power in a boiler is not so much in the steam as in the heated water. With a working pressure of 60 pounds, each cubic foot of steam in the boiler will produce only 4.65 cubic feet of steam, at atmospheric pressure; but 1 cubic foot of water in the boiler will produce nearly 35 times that amount, as at 60 pounds pressure the tempera- ture of the water is 307.5°, or 95.5° above the boil- iug-point, at atmospheric pressure; and, as every degree of heat added to water already at 212° may be taken as competent to generate 1.7 cubic feet of steam, 95.5° will produce 162.35° cubic feet, or nearly 35 times as much as 1 cubic foot of steam, at 60 pounds pressure. It will be seen from the above that, notwithstanding the general opinion that the presence of a steam-dome is essential for obtain- ing dry steam and as a remedy for priming, it should be regarded as not only a useless and expensive appendage to a boiler, but a source of real weakness and danger; the practice of cutting a dome-hole in the shell of a boiler, without providing for the weakening of the plate by some other means, should be looked upon as a very mischievous and danger- ous practice. When it becomes necessary to have a dome, as in case of limited steam-room, or where the arrange- ment of the tubes or flues is such as to make it necessary to carry the water high in the boiler, the hole in the plate under the dome should not be cut 56 USE AND ABUSE OF larger than is sufficient to allow a free escape of the | steam from the boiler to the dome, or to admit of a convenient adjustment of the dome-braces. In most marine boilers the steam-dome is constructed either inside or around the smoke-pipe, and, though not adding much to the cubic capacity of the steam- room, has the effect of superheating the steam, or imparting to it an extra heat, which greatly increases its expansive force, and renders it less liable to condense in the passages between the boiler and the cylinder. = 0200 lb 00000 Lil = 0 coo arpne °° o dt MUD-DRUMS. As will be seen by the above cut, the mu drum is a small cylindrical vessel, ordinarily about twenty-four inches in diameter, attached to the under side of a steam-boiler for the purpose of receiving the feed-water before it enters the boiler, and collect- ing and retaining the mud or other impurities that may be contained in the water; and also for the THE STEAM-BOILER. 57 purpose of imparting heat to the feed-water before entering the boiler. When we consider the short life of the mud-drum, which rarely exceeds six or seven years, and also the expense of removing it and replacing it with a new one, its use in any case becomes a question of doubtful economy. Steam-users and engineers for a long time enter- tained the belief that mud-drums were beneficial, inasmuch as they imparted extra heat to the feed- water, and retained the mud that would otherwise have been carried into the boiler. Experience, however, has shown this to be a grave error, as mud- drums impart very little heat to the feed-water, and retain nothing but the earthy matter which is held in suspension in the water, while all the destructive carbonates that are held in solution are carried into the boiler. A good deal has been said and written, and many theories advanced, to account for the pit- ting or honey-combing of mud-drums, but the mys- terious manner in which it occurs, and its peeuliar character, have not as yet been fully explained, as scientific men are still unable to assign even a plausi- ble cause. The most probable cause for this singu- lar pitting or rotting away might be assigned to the location of the drum, as it receives, on the upper side, nearly all the heat imparted to it, and has not enough on the lower side to keep the iron perfectly dry, and to prevent the rusting of the plates and rivet-heads. 58 USE AND ABUSE OF WATER-SPACE AND STEAM-ROOM IN STEAM. BOILERS. The cubic contents of a steam-boiler may be divided into two parts, namely, that occupied by the water, and that which is occupied by the steam, each of which has, of necessity, a very narrow limit of variation, though they differ very materially for dif- ferent boilers. In the case of a locomotive, it is almost impossible to fix any ratio whatever between the water-space and steam-room, 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 hmited by the same considerations that restrict the water-space. According to Bourne and Armstrong, the water- space should be three-fourths, and the steam-room one-fourth, the whole internal capacity of the boiler. For the boilers of stationary engines, these proportions give very satisfactory results ; and for locomotive and marine boilers two-thirds water-space and one-third steam-room are the proper proportions. In the case of the marine boiler, it is, of course, necessary to have sufficient water to keep the flues and crown-sheets from becoming bare when the vessel is pitching in a rough sea. So also in the case of the locomotive, it is necessary to have sufficient water to cover all the ~ THE STEAM-BOILER. 59 parts exposed to the direct action of the fire when the engine is ascending or descending steep grades. The proportions of steam-room for all boilers are based on the idea that a certain reserve of steam is desirable in proportion to the amount of water evap- orated per hour, and that that reserve should never in any case be less than twelve times the capacity of the cylinder. DIAMETER AND LENGTH OF STEAM-BOILERS AND THICKNESS OF BOILER-PLATE. The diameter of steam-boilers must be determined _by the ends which they are desired to meet, and the objects for which they are employed; also the tensile strength of the material, and the internal pressure to which they are to be subjected. For the same in- ternal pressure and the same material, the thickness for different diameters must: be proportional to the diameters of the boiler; for extra pressures, either the diameter must be decreased, or the thickness of the material increased, which also increases the weight. As the thickness of boiler material for or- dinary high-pressure. use must range from three-six- teenths to seven-sixteenths of an inch — inasmuch as any material thinner than the former can hardly be calked, and if thicker than the latter is difficult to rivet, except with machinery — the extreme limit to the diameters of boilers for high-pressure steam must 60 USE AND ABUSE OF be about sixty inches. The boilers of low-pressure engines are frequently made from one hundred to one hundred and twenty inches in diameter, but they are intended to sustain a pressure of only about twenty pounds to the square inch. Length of Boilers.— The strength of a boiler to resist internal pressure is not affected by its length, except what is due to the stress or sag, induced by the weight of the boiler itself. Boilers may be viewed as having certain relations to girders 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 as in the case of the steam-boiler. But, unlike the girder, the boiler is exposed to high temperatures, and to deteriorations induced by the extreme limits of expansion and contraction, which have a tendency to cause it to bend or sag in the middle. It has been demonstrated by practical ex- periment and observation, both in this country and in England, that there is nothing to be gained by the use of long boilers, and that the extreme length of plain cylinder boilers should never exceed seven times their diameter; of flue boilers, six times; of a tubular and double-deck, five times; and of loco- motive boilers, from three to four times their respec- tive diameters. Thickness of Boiler Materials.— There appears to be a wide difference of opinion among engineers HE STEAM-BOILER. 61. as to the thickness of the material capable of pro- ducing the most satisfactory results in an economical point of view within the bounds of safety. It is generally admitted that the thicker the boiler iron and the poorer its conducting qualities, the greater will be the loss of heat; and that the thinner the material, provided it possesses sufficient strength and good conducting properties, the less resistance is offered to the passage of the heat from the furnace to the water. Boilers made of a superior quality of iron may be thinner and lighter, and consequently more economical as to first cost; but it is claimed, on the other hand, that there is no difference in point of economy between thick and thin plates except in first cost, provided that they are of the same quality ; as, while it requires less fuel to raise the temperature of the water to the boiling-point in the thin boiler than it will in the thick one, the latter will generate more steam with a given quantity of fuel in a given time than the former. EVAPORATION IN STEAM-BOILERS. As the particles of water rise heated from the bottom of the boiler, other particles necessarily sub- side into their places; and it is a point of consider- able importance to ascertain the direction in which the currents approach the plate to receive heat. 228 Ae o2a =) 280 i) oS oO } o8o aa a a Aas =i aa g md aS | O8% a2 | O8s o3 | o8s Lee 7 ae Bee ics ae ae at 22 | $282 || 228 | $888 || 222 | $888 A < ¥ < Ay < 0.25 | .022794 10 .005698 70 =| .001015 0.5 021164 20 003221 80 | .000892 1 018515 30 002244 90 | .000796 2 014814 40 001723 100 | .000719 3 012345 50 .001398 150 | .000481 4 010582 60 001176 200 | .000364 5 j -909259 16 182 USE AND ABUSE OF TABLE OF COMPARISON BETWEEN EXPERIMENTAL RESULTS AND THEORETICAL FORMULA. Boiler Pressure, 45 Pounds. Boiler Pressure, 75 Pounds. Area of | Area of Area of Rea of : Opening | Opening . Opening pening Seo found by jaccording oe found by | according vei Experi- to ; Experi- to ment. | Formule. ment. | Formule. Sq. Feet. | Sq. Ins. | Sq. Ins. Sq. Feet. | Sq. Ins. | Sq. Ins, 100 : 089 09.2 aps POD 12 Ag 200 180 LQ 200 24 24 500 45 48 500 9 9 1000 89 94 |} 1000 1.20 1.18 2000 1.78 1.90 2000 2.40 2.37 5000 4.46 4.75 5000 6.00 5.99 Now, if we compare the area of openings, accord- ing to these experiments, with Zeuner’s formula, which is entirely theoretical, it will be observed that the results from the two sources are almost identical, or so nearly so as not to make any very material difference. In the absence of any generally recog- nized rule, it is customary for engineers and boiler- makers to proportion safety-valves according to the heating-surface, grate-surface, or horse-power of the boiler. While one allows 1 inch of area of safety- valve to 66 square feet of heating-surface, another gives 1 inch area of safety-valve to every 4-horse power; while a third proportions his by the grate- surface,— it being the custom in such cases to allow 1 inch area of safety-valve to 17 square feet of grate- surface. This latter proportion has been proved by THE STEAM-BOILER. 188 long experience and a great number of accurate ex- periments, to be capable of admitting of a free escape of steam without allowing any material increase of the pressure beyond that for which the valve is loaded, even when the fuel is of the best quality, and the consumption as high as 24 pounds of coal per hour per square foot of grate-surface, providing, of course, that all the parts are in good working order. It is obvious, however, that no valve can act without a slight increase of pressure, as, in order to lift at all, the internal pressure must exceed the pressure due to the load. The lift of safety-valves, like all other puppet- valves, decreases as the pressure increases; but this seeming irregularity is but what might be required of an orifice to satisfy appearances in the flow of fluids, and may be explained as follows: a cubic foot of water generated into steam at one pound pressure per square inch above the atmosphere, will have a volume of about 1600 cubic feet. Steam at this pressure will flow into the atmosphere with a velocity of 482 feet per second. Now suppose the steam was generated in five minutes, or in 300 seconds, and the area of an orifice to permit its escape as fast as it is generated be required, 1600 divided by 482 x 300 will give the area of the orifice, 13 square inches. If the same quantity of water be generated into steam at a pressure of 50 pounds above the atmosphere, it will possess a volume of 440 cubic feet, and will flow 184 USE AND ABUSE OF into the atmosphere with a velocity of 1791 feet per second. The area of an orifice to allow this steam to escape in the same time as in the first case, may be found by dividing 440 by 1791 x 300, the result will be .; square inches, or nearly % of a square inch, the area required. It is evident from this that a much less lift of the same valve will suffice to dis- charge the same weight of steam under a high press- ure than under a low one, because the steam under a high pressure not only possesses a reduced volume, but a greatly increased velocity; it is also obvious from these considerations that a safety-valve, to dis- charge steam as fast as the boiler can generate it, should be proportioned for the lowest pressure. RULES. Rule for finding the Weight necessary to put on a Safety-valve Lever, when the Area of Valve, Pressure, etc., are known.— Multiply the area of valve by the pressure in pounds per square inch; multiply this product by the distance of the valve from the ful- crum; multiply the weight of the lever by one-half its length (or its centre of gravity); then multiply the weight of valve and stem by their distance from the fulerum ; add these last two products together, subtract their sum from the first product, and divide the remainder by the length of the lever: the quo- tient will be the weight required. THE STEAM-BOILER. 185 EXAMPLE. Area of valve, 12 inches. 65 13 8 Pressure, 65 pounds, 13 16 4 Fulcrum, 4 inches. za Wa fe Length of lever, 32 inches. Si aa a Weight of lever, 13 pounds. ety pies Weight of valve and stem, 8 pounds, 3190 208 240 32 32)2880 240 90 lbs. Rule for finding the Pressure per Square Inch when the Area of Valve, Weight of Ball, ete; are known.— Multiply the weight of ball by length of lever, and multiply the weight of lever by one-half its length (or its centre of gravity); then multiply the weight of valve and stem by their distance from the fulerum. Add these three products together. This sum, di- vided by the product of the area of valve, and its distance from the fulcrum, will give the pressure in pounds, per square inch. EXAMPLE, Area of valve, 7 inches. 50 12 6 Fulcrum, 3 inches. 30 15 3 Length of lever, 30 inches. BIE vid h 0 Weight of lever, 12 pounds. cee ae i Weight of ball, 50 pounds. 18 EE Weight of valve and stem, 6 pounds. 180°. 21)1698 3 80.85 lbs, 21 1 * 186 USE AND ABUSE OF Rule for finding the Pressure at which a Safety-valve is Weighted when the Length of Lever, Weight of Ball, ete., are known.— Multiply the length of lever in inches by the weight of ball in pounds; then mul- tiply the area of valve by its distance from the fulerum ; divide the former product by the latter: the quotient will be the pressure in pounds per square inch. EXAMPLE. Length of lever, 24 inches. 52 Weight of ball, 52 pounds. 24 Rlow Fulcrum, 3 inches. Area of valve, 7 inches. an 104 91)1248 59.42 Ibs. The above rule, though very simple, cannot be said to be exactly correct, as it does not take into account the weight of the lever, valve, and stem. Rule for finding Centre of Gravity of Taper Levers for Safety-valves.— Divide the length of lever by two (2); then divide the length of lever by six (6), and multiply the latter quotient by width of large end of lever less the width of small end, divided by width of large end of lever plus the width of small end. Subtract this product from the first quotient, and the remainder will be the distance in inches of the centre of gravity from large end of lever. THE STEAM-BOILER. 187 | EXAMPLE. Length of lever...... PG BY BREN Ra be eR Pl 36 inches. Width of lever at large end.) so: teessnnescisstovesasiese a ab PV TOtEAGL Je Ver Ab. SMA CENG aiscaceaces besmer vdcance hae 36 + 2=18—1.2=—16.8inch. 36+6=6kK1=6+5=1.2. Centre of gravity from large end, 16.8 inches, The safety-valve has not received that attention from engineers and inventors which its importance as a means of safety so imperatively deserves. In the construction of most other kinds of machinery, continual efforts have been made to insure accuracy ; while ip the case of the safety-valve, very little im- provement has been made either in design or fitting. It is difficult to see why this should be so, when it is known that deviations from exactness, though trifling in themselves, when multiplied, not only affect the free action and reliability of machines, but frequently result in serious injury, more particularly in the case of safety-valves. Safety-valves should never be made with rigid stems, as, in consequence of the frequent inaccu- racy of the other parts, the valve is prevented from seating, thereby causing leakage; as a remedy for which, through ignorance or want of skill, more weight is added on the lever, which has a tendency to bend the stem, thus rendering the valve a source of danger instead of a means of safety. The stem should, in all cases, be fitted to the valve with a ball 188 é USE AND ABUSE OF and socket-joint, or a tapering stem in a straight hole, which will admit of sufficient vibration to accommodate the valve to its seat. It is also advisa- ble that the seats of safety-valves, or the parts that bear, should be as narrow as circumstances will permit, as the narrower the seat the less liable the valve is to leak, and the easier it is to repair when it becomes leaky. All compound or complicated safety-valves shouid be avoided, as a safety-valve is, in a certain sense, like a clock— any complication of its parts has a tendency to affect its reliability and impair its accuracy. WITTINGHAM’S TUBULOUS BOILER. This boiler, shown on opposite page, may be said to consist of a series of tubes, a steam- and a mud- drum. The tubes are placed angularly, and the two drums are placed horizontally and transversely to the tubes. There is also a water-drum, which is added or not, as circumstances may demand. Inside these tubes are others, of much smaller diameter, which pass entirely through the larger ones and the castings. These inner tubes are threaded at each end, and nuts on them, with faced collars, enable them to serve as both stay-bolts and flues, as, by screwing up the nuts, the outer tubes are pressed into their seats, and tight joints are secured. The mechanical construction of this boiler is of the most perfect character; it ee a THE STEAM-BOILER, : 189 GUE LD 1, Vitis sgt ZA Wey YM we = Vs = ——= — = is very durable, and keeps perfectly tight. It has a good reputation for efficiency, durability, and economy. FOAMING IN STEAM-BOILERS, ‘The tendency of the water in a steam-boiler to rise into the cylinder is well known to engineers, and is generally attributed to the presence of dirt, grease, and other soapy substances. But it frequently arises 190 USE AND ABUSE OF from a disturbance of the relation existing between the temperature and elasticity of the steam in the boiler, as, when the discharge of steam is out of pro- portion to the steam-room in the boiler, the high temperature required to generate steam with suffi- cient rapidity to supply the demand causes violent boiling, and the agitation is greater when the relation between the temperature and pressure is most dis- turbed. This is often the case with tug-boats just starting to tow a heavy vessel, or a locomotive starting a train of cars, and even with stationary boilers hay- ing too limited steam capacity, when a heavy piece of machinery is thrown on. The most common causes of foaming are insuffi- cient steam-room, foulness of boilers, excessive firing, and the effects produced by the intermittent action of the steam-valves. The supply of steam to the cylinder being cut off for a considerable period during each stroke, the effect is to throw the water in the boiler into a slight undulatory motion, as may frequently be observed in the glass water-gauge. Foaming in locomotive boilers is generally caused by impurities in water, which are confined to certain parts of the country known as the alkali regions; these impurities consist essentially of potash, soda, ammonia, and lithia. Locomotive boilers using sur- face water are also apt to foam if allowed to become dirty, in consequence of decayed vegetable matter being held in suspension in the water, such sedimen- THE STEAM-BOILER. 191 tary accumulations adding to the strength of the ingredients above referred to. Foaming in marine boilers is most generally caused by changing the water from salt to fresh, or vice versa, and is made evident by the boiling up of the water in the glass gauge. When foaming arises from this cause, the water in the boiler should be changed as soon as possible, which can be done by putting on a strong feed and blowing out con- tinuously, or at short intervals; and it may become necessary to throttle down the steam, cut off short by the link, or even to stop the engine in order to ascertain the level of the water in the boilers, when it will frequently be found to have fallen below the proper level. Violent foaming can be checked by opening the furnace door and damper, and covering the fire with fresh coal; but this means of relief should be used as little as possible, because it has a tendency to injure the boiler, owing to the sudden contraction of the parts most exposed to the fire. Foaming is also inherent in some types of boilers, in consequence of their peculiar construction, which prevents a free escape of the steam from the heating- surface to the steam-room. Boilers with a large amount of heating-surface and small steam-room generally foam ; so also do boilers with the ordinary amount of steam-room, if the water be carried too high. Various expedients have been resorted to, such as perforated pipes, baffle-plates, etc., to counter- 192 USE AND ABUSE OF act the dangers induced by foaming, but without any permanent results. Experience has shown that the most reliable preventives of foaming are, ample steam-room, good circulation, clean boilers, and moderate firing. All the phenomena connected with foaming have not yet been satisfactorily explained ; but, from whatever cause it may arise, it is always attended with a certain amount of danger, Foaming is sometimes confounded with priming, but they arise from very different ‘causes, and are productive of very different results. Foaming may result in per- manent injury to a boiler, or even induce explosions, while priming can only cause a waste of fuel and loss of power. Foaming is always made manifest by the violent agitation and rising and falling of the water in the gauge, and also the muddy appearance of the water, and the great quantity of particles of sediment contained in it that have been brought up from the | lower part of the boiler by the violent ebullition of the water. Priming may and does go on unseen, but it can be discovered by the white appearance of the steam as it issues from the exhaust-pipe ; as saturated steam, or steam containing water, has a white appear- ance and descends in the shape of mist, while dry steam has a bluish color, and floats away in the atmosphere. Priming also makes itself known by a clicking in the cylinder, which is caused by the piston striking the water against the cylinder-head at each end of the stroke. ig has been too much the custom heretofore for owners of Steam-boilers to disregard _ the advice and suggestions of their own engi- neers and firemen, even though men of intel- ligence and experience, and to be governed entirely by the advice of self-styled experts and visionary theorists. 17 N 193 194 USE AND ABUSE OF INCRUSTATION IN STEAM-BOILERS, All natural waters contain more or less mineral matter. ‘This is acquired by contact with the earth’s surface, and by percolation through the soil and rocks. It consists principally of carbonates of lime and magnesia, sulphate of lime, and chloride of sodium, in solution, and clay, sand, and vegetable matter, in suspension. The many other saline in- gredients found in various waters exist in very small proportions, are generally very soluble, and, therefore, have no relation to the utility of water in boilers. Of the above-mentioned salts, the carbo- nates of lime and magnesia are only soluble when the water contains free carbonic acid — consequently, the waters of rivers, lakes, etc., contain them in less quantities than those of wells, springs, and creeks, owing to the precipitation caused by the spontaneous evolution of the solvent on: exposure to air, heat, and light. Our American rivers contain from two to six grains of saline matter per galion, in solution, and a varying quantity in suspension, generally exceeding ten grains. Well and spring waters hold but little in suspension, but a quantity of the dis- solved salts, varying from ten to six hundred and fifty grains in the gallon. When such water is boiled, the carbonic acid is driven off, and the car- bonates, deprived of their solvent, are rapidly pre- 4 THE STEAM-BOILER. 195 cipitated in a finely-crystallized form, tenaciously adherent to whatever they may first fall upon. Sul- phate of lime requires five hundred parts of water for its solution, and, as the water evaporates, super- saturation occurs, and the salt is precipitated in the same form and with the same adherent quality as the carbonates. Chloride of sodium, and all the other more soluble salts, are precipitated by the same process of supersaturation ; but, owing to their greater solubility, much more evaporation is required. All suspended matter gradually tends to subside. This combined deposit, of which the carbonate of lime usually forms the greater part, remains adhe- rent to the inner surface of the boiler, undisturbed by the force of the boiling currents. Gradually accumulating, it becomes harder and thicker, till it is as dense as porcelain, though tougher, and at length may obtain such a thickness as to prevent the proper heating of the water by any fire that can be placed in the furnace. The high heats sometimes necessary to heat water through thick scale, will sometimes convert the scale into absolute glass, by combining the sand with the alkaline salts composing it. The evil effects of the scale are due to the fact that it is relatively a non- conductor of heat. Its conducting power, compared with that of iron, is as 1 to 37.5. Consequently more fuel is required to heat water in an incrusted boiler than in the same boiler if clean. seocssenseieces 212°?" Fah: Sea-water eveee as 913°2, ee “ oe 914°4 “c (a4 33 915°5 “ “ ed Se ae “ a 917°9 14 (74 3S 2] 91 74 « ve 9203. « s 9915 si yy at Mle hey 10 9933 it 225:0° ii 2261 USE AND ABUSE OF 208 / s A er ae UZ <——s— p——— ae: EXPLODED BOILER OF THE FERRY-BOAT “WESTFIELD.” =. eee THE STEAM-BOILER. 209 STEAM-BOILER EXPLOSIONS. That the use of steam-power is fraught with danger is only too well known; the extent of the danger, however, as indicated by the number of boiler explosions every year, and the loss of life and property entailed, is but vaguely appreciated by the public. No official record is kept of such accidents, and only those of exceptional interest are reported in the newspapers. Even in such cases as are re- ported, it is almost impossible to ascertain their true cause, as there is seldom a unanimous opinion on the part of the experts who examine into the causes after the event; besides, there are a great many people who think they know something that will explain the cause of these fearful accidents, but, for some reason or other, their fine-spvn theories have not been of any practical value. This doubtless arises from the fact that the conditicos under which boilers are used, and the causes of their explosions, are very imperfectly understood by any one except those who have devoted time, thought, and study to their construction, care, and management. Until quite recently, boiler explosions were attrib- uted to one cause only, namely, an insufficiency of water; and this, in turn, was attributed to the care- lessness of the attendant who had charge of the boiler. The boiler was iron, and, of course, it would not, or could not, explode if the vagabond fireman 13% O 210 USE AND ABUSE OF had not let the water get low. The boiler might, in the first place, be made of an inferior quality of iron; might be constructed in the most bungling manner; the fittings might not only have been of the most inferior kind, but inadequate in every re- spect. In fact, it might be burned, banged, abused, or crystallized through excessive firing, or it might be cracked, patched, corroded, and taxed beyond its strength; and when patience ceased to be a virtue, it exploded. It was sure to bring down the censure, if not the vengeance, of the community on the devoted head of the unfortunate engineer or fire- man; and if, perchance, his life was saved, he was sure to be ostracized and driven out, as though it were, from the face of the Lord. Strange as it may seem, this monstrous belief was not confined to timid people alone, but was entertained very largely by a class of men styling themselves scientific experts. Of course, in the face of such ignorance and stupidity, it would be useless to attempt to prove that some of the most destructive explosions that ever occurred in this country took place when there was a suffi- ciency of water in the boiler. Another of the stereotyped causes of explosion was tampering with the safety-valve. That adjunct of the steam-boiler might be out of all proportion ; it might be miserably constructed ; in fact, it might be an unsafety-valve instead of a safety-valve — but what difference did that make when the boiler ex- THE STEAM-BOILER. 211 ploded? No one took interest enough in the matter * to ascertain its proportions, or the manner in which it was fitted, so that the blame, if blame there was, might rest where it rightfully belonged, viz., on the party who attached such an abortion to the steam- boiler. All cheerfully united in cursing the fireman if living, and blasting his memory if dead. Verily, those who chose the care and management of the steam-boiler as a calling in the past, as well as those who intend to do so in the future, ought to feel grateful to the men who stripped boiler explosions of the mystery that so long enshrouded them, and attributed them to their real causes. More recently, the theory that electricity was an active agency in steam-boiler explosions was quite rife; but Faraday and other eminent chemists proved conclusively that the development of electricity in the steam-boiler, if such a phenomenon could at all occur, would be due solely to the friction of the steam against the sides of the vessel; that the pres- ence of electricity would be more likely to occur in the steam-pipe or in the steam-cylinder than in the boiler, and that all the experiments, investigation, and researches fail to discover the presence of elec- tricity in steam. Even if it were a fact that the pres- ‘ence of electricity did actually exist in steam, how was it to accumulate? it certainly could not be done when the boiler was not in use, as there would be no friction to create it; and when the boiler was in use, 212 USE AND ARUSE OF if such a thing could exist, the electricity would escape through the safety-valve and steam-pipe, or ~ any of the openings, with a velocity more than one million times faster than steam at two hundred and forty pounds to the square inch. Besides, boilers and their connections are conductors, the same as light- ning-rods; and if electricity existed in the boiler, it would soon find its way to the ground. Explosive Gases.— This theory was, in its turn, urged as one of the main causes of boiler explosions, and it was claimed that large bodies of steam were decomposed by being brought in contact with red- hot plates, and that gas was formed with such rapid-— ity and elastic force that no boiler structure was sufficiently strong to withstand it. But it was shown by thousands of practical experiments that only a very small quantity of steam could be decomposed by being brought in contact with the parts of steam- boilers most likely to become heated; and that even then it would not be dangerous, as the hydrogen is not explosive, unless mixed with its equivalent of oxygen, when it would have to be ignited with a spark to produce explosion. Again, assuming that nearly all the steam can be decomposed, the hydro- gen would only burn quietly in the presence of oxygen, as it becomes liberated on the red-hot sur- face of the plates and fails to produce an explosion. But to take the extreme view of the case, assuming a sudden and perfect union of the gases to take THE STEAM-BOILER. Lhe place, it would still be difficult to see how an explo- sion could take place, as neither the volume nor pressure would be increased. | Concussive Ebullition.— Then the phenomenon termed concussive ebullition was advanced as a cause of boiler explosions. This theory was founded on the experiments of Dufour, who claimed that by suspending drops of water in heated oil, the temper- ature of the water might be raised considerably above the boiling-point without the formation of vapor, but that if a bubble of air or a particle of any porous substance was placed in contact with the water a burst of vapor immediately occurred. Now if this theory should be shown to be correct, sensible people would be at a loss to know what relation or what similarity of conditions can exist between drops of water suspended in oil and a steam-boiler in ordi- nary use. It was also claimed that the presence of oil in steam-boilers would cause them to explode; but this theory lost much of its weight from the fact that oil is frequently used for preventing incrustation, and that the boilers in which it is used do not ex- plode. It is also well known that oil is very liber- ally used in the making of steam-boilers, and that there is hardly one that has not had more than a gallon of oil smeared over its surface in the different processes of manufacture. Spheroidal Theory. — The spheroidal theory is the so-claimed tendency of water, when thrown upon 214 USE AND ABUSE OF highly heated plates, to assume the spheroidal con- dition, and to evaporate suddenly when the temper- ature is sufficiently lowered. The exact application of this theory is by no means clear, and the assumed delay of the water in evaporating is antagonistic to the sudden evaporation from the overheating theory, as it is difficult to see how the evaporation of a large quantity of water in an ordinary boiler could be de- layed (as is assumed in this theory) without reducing the temperature of the water below that sufficient to produce an explosion. It is well known that water in this state evaporates very slowly, and this has been attributed to the supposed fact that the heat was transmitted through the spheroids; but Bou- tigmy attributes it to the reflection of heat from their surfaces, showing that they do not absorb heat. All the foregoing magnificent theories have been disproved through the operations of the Hartford Steam-Boiler Inspection and Insurance Company. Proof of this is found in the fact that whenever manufacturers and steam-users place their boilers in the care of this Company they are sure to receive immediate and full protection from steam-boiler ex- plosions. As it is noticeable that the electricity immediately gives out, that the drops of water fail to suspend in heated oil, or even form into spheres and roll over the surface of the plates like spinning- tops, that the gas fails to generate in volumes that would place a Wilcox’s fire-annihilator in the shade, THE STEAM-BOILER. 218 and that the water refuses to thump against the sides of the boiler, when the intelligent and experienced inspector comes to do so with his hammer and chisel, he would be very likely to say that either such theo- ries or the plates were a “little too thin,” or perhaps both. To compensate for the absence of so many splendid phenomena, there is always sure to be an immense discovery of broken braces, cracked seams, bulged plates, distorted crown-sheets, defective steam- gauges, and inferior safety-valves. The principal causes of explosion, in fact the only causes, are deficiency of strength in the shell or other parts of the boilers, over-pressure, and over-heat- ing. Deficiency of strength in steam-boilers may be an original defect, arising in the material or workman- ship at the time of construction, or it may be due to deterioration from use, to ordinary wear, or to inju- ries arising from mismanagement, want of attention, and repairs, etc. It often happens that boilers are deficient in strength for the pressure they are in- tended to bear, and no accumulation of pressure be- yond this is necessary to bring about their destruc- tion. Deficiency of strength arising from bad workmanship is the most difficult to discover, and not unfrequently escapes the closest scrutiny, more particularly so in the case of flue, tubular, and loco- motive boilers, as their examination is attended with certain difficulties. Over-pressure niay be caused by the safety-valve 216 USE AND ABUSE OF being recklessly overweighted, by the sticking of the valve on its seat, by the inadequate size of the com- munication between the boiler and the valve, or by an incorrect or worthless steam-gauge. Boilers are frequently found running at a pressure which is regarded -as perfectly safe, but when the gauge is examined and compared with one known to be cor- rect, it is found to be 10, 20, or even, as is some- times the case, 50 pounds out of the way. If a boiler supposed to be running under a pressure of 80 pounds is found, in consequence of an unreliable steam-gauge, to be actually running at a pressure of 120 to 130 pounds, the limit of safety may have been passed, and an accident is imminent, which may occur at any moment. Over-heating induced by excessive firing is no doubt the cause of many explosions, and most fre- quently occurs when the boiler is too small for the engine, or incapable of furnishing the required amount of steam, as the intensity of the fire neces- sary to generate the desired quantity of steam has a tendency to repel the water from the plates. The same effect may be produced when there is a great disproportion between the grate- and heating-surfaces, or where the heat from a large grate is concentrated on a small space. Under such circumstances, the heat is delivered with such intensity as to lift the water from the surface of the iron, thereby exposing it to the direct action of the fire. Explosions occur-— THE STEAM-BOILER. 217 ring from excessive firing are in all cases the result of avarice, ignorance, or a want of skill in the care and management of the steam-boiler. Over-heating may be caused by the accumulation of hard, solid incrustation adhering to the parts most exposed to the direct action of the fire, or it may be due to shortness of water, which may result from leakage of the valve or stop-cock, to a failure in the supply- pipe, or neglect to turn it on at the proper time or in sufficient quantity. A steam-boiler may be well designed, made of good material, and of first-class workmanship, and yet in a few months after being put under steam it may explode with terrible effect. On examining into the cause of the explosion, it may turn out that the water which was used made a heavy deposit; that the boiler had not been cleaned out since it was put in use; that the fires had been fiercely urged, and the water driven from the surface of the iron; asa result, the life had been entirely burnt out of the sheets directly over and around the fire, thereby weakening the boiler and putting it in a dangerous condition. That the sudden heating or cooling and oxidation of the boiler induce great deterioration of strength has been proved by experience. Defects in the material, as blisters, lamination, arising either from their inferior quality or want of care in the manufacture, are other sources of weakness in steam- boilers. 19 218 USE AND ABUSE OF A great deal more might be written on this sub- ject if needed, but suffice it to say that there is no mystery about steam-boiler explosions; they are all regulated by cause and effect; and it will be found, on investigation, that seven-tenths of all the boiler explosions that occur yearly in this country might be traced to some sufficient cause, were all the facts known. Even if there is some apparent mys- tery connected with boiler explosions in some in- stances, it will vanish before sound and careful investigation. The solution may involve the exami- nation of a great number of boilers and extend over years, but the greater the number examined, with their particular defects understood and explained, the greater will be the fund of information from which to draw conclusions. No amount of theory will explain the different causes of explosions, as that can only be determined by a full comprehension of the circumstances under which they occurred, which involves the quality of the material of which they are constructed, character of workmanship, form or type of boiler, setting, attachments, properties of water used, kind of fuel, age, treatment, and skill employed in the care and management. These are the vital points to be considered in order to arrive at any approximate solution of the cause or causes of steam-boiler exp:osions. The sooner steam-users and engineers discard all theories in conneciion with steam-boiler explosions, THE STEAM-BOILER. 219 and come to the conclusion that when a boiler ex- plodes one of two things is certain — either that the pressure was too great for the boiler, or that the boiler was not equal to the pressure; that it gave way in the weakest place, and that the strength of any machine (the steam-boiler included) must be measured by its weakest point, and that the sooner this principle is universally recognized the better it will be for every steam-using community. A weak spot, a flaw, or a crack in a boiler does not improve by use, and when any machine breaks down at a point which shows that it must have been weak for a long time, no one thinks of going into a long dis- cussion or explanation of the mysterious agencies which were suddenly brought to bear on it and cause it to break. Not so, however, with a steam-boiler ; it may have been burned, corroded, and cracked for years, and when at last it explodes there are always to be found those who wish to involve the whole thing in mystery and tell how it must have occurred, who are always unable to tell how it might have been prevented. ‘Within the past eight years, mainly through the operations of the Hartford Steam-Boiler Inspection and Insurance Company, steam-boiler explosions have been stripped of the mystery in which vision- ary theorists had so long enshrouded them, and the belief in such heresy as mysterious steam-boiler ex- plosions is principally confined to those who are 920 USE AND ABUSE OF incapable of or unwilling to be convinced, even when the facts are laid before them. The class of persons, of all others, that ought to encourage such theories, and take refuge behind them, when called upon to pay damages in case of accident, are those who discard such theories when accounting: for boiler explosions, and the correctness of their views is suf- ficiently attested by the almost entire absence of serious accidents in connection with the thousands of boilers of all sorts and conditions that are or have been in their care for several years past. Few have any idea of the extent to which steam is used in our large cities, or of the risks to which even those who have no interest in the boilers, and who are not connected in any way with the business in which they are used, are exposed. In almost every building along our principal thoroughfares may be found a large boiler, used for heating pur- poses or for furnishing power, which is concealed from public view. It is only when the public are startled by an explosion, and by the death or injury of innocent persons, that the true condition of things is revealed, and that the dangers incurred by every passer-by are exposed. HE opinions of wise men, who are willing to investigate for the purpose of gaining and giving information, are entitled to due respect and consideration. But when theo- ries and opinions are promulgated that have no truthful basis upon which to rest, and which seem to have no end save that of exalt- ing the promulgator, it is the duty of those who have had practice and experience to counteract such influences, and show how much labor can be expended in mystifying and clouding a subject which might other- wise be comparatively simple. 19.4 ic tek USE AND ABUSE OF EXPLODED BOILER OF THE LOCOMOTIVE “CHARLES WILLARD yy THE STEAM-ROILER. 223 EXPERIMENTAL BOILER EXPLOSIONS. Several attempts have been made, and large sums of government money expended, to ascertain the cause of steam-boiler explosions by experiment ; but such experiments have failed to shed any light on the subject, as they must ever do, in, conse- quence of the circumstances under which _ boilers are made and used being so different. Take, for instance, two boilers of the same dimensions in every respect, and of the same material and workmanship, to be used in different parts of the country and under entirely different circumstances. One may explode with disastrous effects, while the other may remain perfectly safe and sound. Now what rela- tion can be established between the danger or safety - of either, unless all the circumstances connected with their care and management be known, viz., proper- ties of water, character of the setting, condition of the boiler, care and management, etc. A boiler of a peculiar type may be selected for the purpose of testing what pressure it would take to burst or ex- plode it. The first thing to be done in such a case would probably be to see that the joints were all steam- and water-tight, and that the braces were all taut, and everything restored as nearly as possible to its original condition. The explosion may establish the fact that the boiler sustained a pressure of two or 224 USE AND ABUSE OF three hundred pounds to the square inch before giving away. Now, perhaps, there may be located in the same neighborhood a boiler of the same type, made by the same manufacturer, of the same thick- ness and brand of iron, and by the.same mechanics ; but it may have some inherent defect, due either to the material or the workmanship. It may have been badly cared for, burned, bulged, crystallized, cracked, or corroded ; then, if it should explode, what relation would it bear to the other, save simply in type? What criterion would it establish by which to deter- mine the safe working or bursting pressure of all classes of boilers, or even those of the same type? The following instance came to the knowledge of the writer, which goes to show how futile any attempt must ever be to establish the cause of steam-boiler explosion by experiment. An engineer undertook to apply the hydrostatic test to the boiler in his charge; and, to accomplish his object, he placed a quantity of grate-bars on the lever of the safety-valve, and by means of a force-pump raised the cold-water pressure to one hundred and twenty pounds to the - square inch, without the boiler showing any signs of weakness or leakage, although it had been in use nine years. The test was considered satisfactory ; the water was then run down to the proper level, the fire started, and it was only when steam blew off at the safety-valve that the engineer remembered that he did not remove the grate-bars from the THE STEAM-BOILER. 225 safety-valve lever. He then drew his fire, and allowed the boiler to cool, and when the grate-bars were taken down and weighed, it was ascertained that the boiler sustained a steam-pressure of three hundred and seven and one-half pounds to the square inch. 3 Another boiler of the same type, located in the same neighborhood, built by the same manufacturers, and as nearly alike in every respect as possible, showed signs of leakage when only two years in use; but, as the cause of the leakage was concealed under a mass of masonry, it was impossible .to ascertain what the nature of the defect was. An experienced boiler-inspector was called in, and, after removing a portion of the brickwork by which the boiler was enveloped, he discovered that the material was cracked through between thirteen rivet-holes in one of the seams a little below the water-line, and that the heads of three of the rivets in that part of the seam that was sound had dropped off, in consequence of being cold-shutted in the process of riveting. Such a boiler would, in all probability, burst or explode under a pressure of less than one hundred pounds to the square inch, which goes to show that the cause of boiler explosions can never be deter- mined by experiment. This can only be ascertained by a knowledge of all the circumstances connected with each individual case. uh 226 USE AND ABUSE OF ao ey eon wt GY = FZ Wa ay ty Ue > NS WA: Wy yg ANALY Yi AZ -—¢ tO LI. 3 S : Lie WBALAYYUZ WH VIII. S SS 2 jj; \Z nigga 7 WDYACHTHAG — titi, Z Alita 7, GG > | (LEZ . ZY releerat ictiad tear te Ny S577 ZA WLIW NRA eZ LIN LP, SS) ZZ BANU ih PICMAVIINA WN ZINN CU LL : NIE UT Nt 7 WN ZZ U5 L4H * AN BIA Ni it MWe CHIN titiizyo Vie i ANN 4) I {| WLAN A INN LLL Zi ie ie) i\, WY ZN Ge \E OSES BN WN So ZINN 7 WAY. AIAN CA AN WV ZA |).§EH pJ—MBE_0” 77” ANY Z LL Fe ee eee ZZZAN ANNO fa SLLLLZ 2 CML ELEY NANNY LLG | ZZ OL LELALZZZA WWW GY. NZ Qin CLLALL LL: NW ZG Za LI WULAAUVHATHULEAA\\W\\“\“WZ LEE ()-.yAXA-'.SW B THE ROOT BOILER. This boiler consists essentially of 80 wrought-iron tubes, 4 inches and 9 feet long. These.tubes are set in brickwork, at an angle of about 30° from the horizontal. The tubes are connected together at the ends by a system of triangular plates and crowfeet. The boiler has a steam-drum 18 inches by 63 feet long. The superheating is effected in the upper por- tion of the boiler. THE STEAM-BOILER. 227 VAGARIES OF EXPERTS IN REGARD TO STEAM-BOILER EXPLOSIONS. The boiler in a plaster-mill in Pennsylvania ex- ploded, killing the fireman instantly, and it was on evidence at the inquest that the boiler was so located that it had no protection from the effects of the weather. It was not known to have been cleaned or examined for ten years. The steam-gauge got out of order and was allowed to fall into disuse, and the gauge-cocks became choked with mud. After the explosion, the safety-valve was picked up more than one hundred feet from where the occurrence took place, and it was so much corroded, that it became necessary to use a hammer to drive it from its seat. An expert was summoned to testify at the inquest, in order that the jury might be able to form their conclusion as to the cause of the fireman’s death, and he stated that the air that afternoon was surcharged with electricity, and that that was undoubtedly the cause of the explosion; he was invited to examine the boiler and its attachments for the purpose of satisfying himself on the subject, but he declined to do so, stating that his mind was fully made up in regard to the cause of the explosion. Two large steam-boilers in a cabinet manufac- tory in Philadelphia had but one safety-valve, which was located on a branch-pipe for the purpose of allowing a stop-valve to be placed between it and 228 USE AND ABUSE OF the boiler, for the purpose of using one boiler at a time if desirable. On one-occasion, when the engine was undergoing repairs, it became necessary to shut down this stop-valve; when everything was ready, in the absence of the regular engineer, one of the workmen was instructed to fire up with wood and shavings, and as all the means of escape for the increasing pressure was cut off, the boiler exploded, killing eighteen men and injuring two others so that they died soon afterwards. A noted expert was summoned before the coroner’s jury to explain if possible the cause of the disaster, and he testified that there was a strong current of electricity passing be- tween the poles that afternoon, and that. its pas- sage was probably obstructed by some dense clouds, which phenomenon was the cause of the explosion. He further stated that if the explosion had not occurred until an hour afterwards, he did not believe it would have taken place at all. The owner of a planing-mill in Michigan, instead of employing a competent person to take charge of us engine and boiler, instructed any of his workmen who could find it most convenient to. fire up, and .an the engine. The water which was used in the Soiler was taken from a mountain stream, and was so impregnated with lime that the pipes became choked, and the boiler became so coated with incrustation that it bulged and cracked in several places, and finally exploded, killing three men and frightfully THE STEAM-BOILER. 229 wounding five others. An expert was sent for in order that his teatimony might shed some light on the cause of the explosion. He stated that there was an extensive belt of ozone extending over that sec- tion of the country, and that wherever the presence of ozone existed in the air boilers would explode, no matter how carefully they were managed. At the investigation that followed the explosion on board the ferry-boat ‘‘ Westfield,” it was shown that the boiler was made of #-inch iron, and 120 inches in diameter. The safe working-pressure of such: a boiler when new, according to Fairbairn, would be from 28 to 80 pounds per square inch. It was in evidence that, though the boiler had been in use twelve years, it was badly cracked and patched, and was carrying a pressure of 40 pounds to the square inch at the time of the explosion. Such a statement of facts would enable any intelligent mind to form a definite conclusion as to the cause of the explosion ; nevertheless, an expert came forward and offered to explain the cause of the disaster, when, on being questioned, he stated that at the time of the explo- sion the boiler was full of inflammable gas, and when asked what kind of gas, he answered that it ‘‘ might a’ bin” oxygen. Experts have always made it an object to mystify the cause of steam-boiler explosion, probably for the purpose of retaining the honor among their fellow- men of being looked up to as the only exponents of 20 oa 230 USE AND ABUSE OF a phenomenon which produces such disastrous results. They seem to imitate the ancient priests, both among the Jews and heathen, who were, from their ordinary duties, necessarily conversant with the generation of steam; but their knowledge of it was mainly exerted to delude men to idol worship and lock their minds in ignorance instead of to benefit and enlighten them. DEFECTS IN THE CONSTRUCTION OF STEAM- BOILERS. The following cuts illustrate some of the mechanical defects that impair the strength and limit the safety and durability of steam-boilers. All punched holes are conical, and unless the sheets are reversed, after veing punched, so as to bring the small sides of the holes together, it will be impossible to fill them with the rivets. Fig. 1 shows the position of the rivet in the hole, without the sheets being reversed; and it will be observed that, as very little of the rivet bears against the material, the expansion and contraction of the boiler have a tendency to work it loose. It is apparent that such a seam would not possess over one-third the strength that it would if the holes in the sheets were reversed and thoroughly filled with the rivet, as shown in Fig. 2. Fig. 3 represents what is known in boiler-making as a blind-hole, which means that the holes do not come opposite each other when the reams are placed together for - a FIG, 1, FIG, 2, FIG, 3 @o G@ FIG, 5, FIG, 6, 232 USE AND ABUSE OF the purpose of riveting. Fig. 4 shows the position of the rivet in the blind-hole after being driven. It will be observed that the heads of the rivet, in con- sequence of its oblique position in the hole, bear only on one side, and that even there the bearing is very limited, and, through the expansion and contraction of the boiler, is liable to work loose and become leaky. Such a seam would be actually weaker than that represented in Fig. 1. Fig. 5 shows the metal distressed and puckered on each side of the blind- hole in the sheets, which is the result of efforts on the part of the boiler-maker, by the use of the drift- pin, to make the holes correspond for the purpose of inserting the rivet. Fig. 6 shows the metal broken through by the same means. Now it will be observed that nearly all the above defects are the result of ignorance and carelessness, showing a want of skill in laying out the work, as well as a want of proper appliances for that purpose. The evils arising from such defects are greatly ag- gravated by the fact that they are all concealed, fre- quently defying the closest scrutiny, and are only revealed by those forces which unceasingly act on boilers when in use. Such pernicious mechanical blunders ought to be condemned, as they are always the forerunners of destruction and death. There can be no reason why boilers should not be con- structed with the same degree of accuracy, judgment, and skill as is considered so essential for all other classes of machinery. THE STEAM-BOILER. 238 IMPROVEMENTS IN STEAM-BOILERS, Until quite recently the steam-boiler has under- gone very little improvement.. This arose, perhaps, from the fact that men of intelligence and mechan- ical genius directed their thoughts and labors to some- thing more inviting and less laborious than the con- struction ofsteam-boilers. Consequently, that branch of mechanics was left almost entirely to a class of men that had not the genius to rise in their profession or improve much in anything they at- tempted. As a result, ignorance, stupidity, and a kind of: brute force were the predominant acquire- ments in the construction of the steam-boiler; but within the past few years this state of things has been changed, as some very important improvements have been made, not only in the manufacture of the mate- rial of which boilers are made, but also in the mode of constructing them. The imposing display of pow- erful and accurate boiler machinery shown at the Centennial Exposition in Philadelphia, is an evi- dence that the attention of eminent mechanics and manufacturers is directed to the steam-boiler, and that in the future its improvement will keep pace with that of the steam-engine. Boiler-plate is now rolled of sufficient dimensions to form the reams for boilers of any diameter with only one seam, obviating the necessity of bringing riveted seams in contact with the fire, as was usually 20 234 USE AND ABUSE OF the case in former times. In the manner of laying off the holes for the rivets, accurate steel gauges have taken the place of the old-fashioned wooden templet, thereby removing the evils induced by blind-holes, and obviating the necessity of using the drift-pin. So, also, in the method of bending the sheets to form the requisite circle—with a better class of machinery, the work is now more accurately per- formed. The old process of chipping is, in nearly all the large boiler-shops, superseded by planing the bevels on the edge of the sheet preparatory to calking. Recent improvements in “calking” have resulted in perfect immunity from the injuries for- merly inflicted on boilers in that process. In most establishments of any repute in this country, riveting is done by machinery, which is (as is well known to all intelligent mechanics) very much superior to hand-riveting. It is only small shops that enter into rivalry to secure orders and build cheap boilers, using poor material and an inferior quality of me- chanical skill, that use the same old crude appliances —in many cases the merest make-shifts—that were in use a quarter of a century ago, and constructed with- out regard to any of the rules of design that are considered so essential in appliances for the con- struction of all other classes of machinery. THE STEAM-BOILER,. 235 SIRS AANA RATAN RUN THE ALLEN BOILER. In this boiler the roof of the fire-chamber is made of nine cast-iron cylinders, each seven inches internal diameter and eleven feet long; and into each of these cylinders eighteen wrought-iron tubes, three and a half inches in diameter, are screwed, the lower ends being closed by plugs. These tubes hang down from the roof into the fire-chamber, and are set at an angle of about twenty degrees from the vertical ; the lower end being farthest from the fire-door. The tubes over the fire are three feet two inches long, the rear ones are four feet five inches long. Steam- drums are arranged over the boiler. Mes Y Engineer should inform himself 4+ on the subject of the safe working press- ure of Boilers, and when he finds the limit of safety has been reached, he should prompt- ly inform his employer, and wse his inflw- ence to have the Boiler worked within the bounds of safety. 236 THE STEAM-BOILER, 6 CARE AND MANAGEMENT OF STEAM-BOILERS. No class of men are entrusted with greater re- sponsibilities, none hold in their keeping more im- portant interests of life and property, than those having the charge of steam-boilers. A mistake in judgment at a critical point, ora careless neglect of duty, may cause, and has often resulted in, terrible destruction to life and property. The most skilful and best-informed engineers, and those best versed in steam matters, are the ones who most fully appre- ciate its dangers, and also the most willing to learn all they, can relative to any new points of interest, danger, or safety. In the management of steam-boilers there are certain rules that must be observed, and to insure faithfulness, the owners of boilers should secure the services of intelligent men — ignorance and careless- ness have been the occasion of too many accidents, and great destruction of life and property has not un- frequently been the result of employing cheap help. In the care and management of steam-boilers, men should be employed who know at least something of the nature of the power with which they have to deal; men who understand the use of the various attachments on steam-boilers; men of good sound judgment who have, if not a thorough, at least a practical knowledge of the strength of iron, of its capabilities to resist pressure, and who know beyond 238 USE AND ABUSE OF what limits they should not allow pressure to accu- mulate. it will be poor consolation to the owner of a steam- boiler, after his property has been destroyed by a ter- rible explosion, to congratulate himself on the fact that he saved a few dollars a month in the wages of his engineer, by employing a careless or incompetent man. But if those who neglect and abuse steam- boilers were the only ones to suffer from explosions, carelessness and mismanagement would be less a matter of public concern; but when the lives of hundreds are often thus exposed to danger, it should be the aim of every steam-user to do his utmost to render the use of steam in his establishment safe, as after an explosion, where persons have been killed or maimed for life, the public verdict is very severe, and no right-minded man would wish to covet any man’s experience or reflections who has laid himself open to public censure by neglecting to do what might have prevented so serious a disaster. A very mischievous practice exists in various parts of the country in reference to starting fires under steam-boilers preparatory to raising steam. This duty is entrusted to ignorant watchmen, who are too often the agents of disaster. These men are instructed to light the fire at a certain hour, and comply with their orders without exercising the least judgment on the subject. Numerous instances are on record where watchmen have started the fires THE STEAM-BOILER. 239 under steam-boilers and raised steam before discover- ing that there was insufficient water in the boilers, thus incurring the risk of burning the boilers, if not actually ruining them. No persons ought to be per- mitted to meddle in any way with the steam-boiler, except those who are skilled in the management of them, and who are fully conversant with the proper- ties of steam. Thousands of lives are lost and much valuable property destroyed through the ignorance of those left temporarily in charge of steam-boilers. It may seem strange, but it is no less true, that, notwithstanding the numerous fatal explosions that have occurred, resulting from defects which could not have escaped the notice of a competent inspecter, many of the users of steam-power appear to be in- different as to the condition of their boilers. They would rather incur the risk of an explosion than stop their works one day in the year, that their boilers may be thoroughly examined. Even then many of them will not be at the trouble or expense of having the boilers properly cleaned and the flues swept, without which a satisfactory examination is impossible. In the majority of cases boilers are not cleaned half as often as they should be. When the water is hard, and scale accumulates on the sides or flues of the boiler, solvents are very often resorted to to remove the scale. After the scale has been thrown down it is frequently allowed to remain there and 240 USE AND ABUSE OF - form a heavy conglomerate coating, which prevents the water from coming in contact with the iron, the result of which is that the parts of the boilers ex- posed to the direct action of the fire are cracked, bulged, or burned through. The yearly report of the Hartford Steam-Boiler Inspection and Insurance Company shows that nearly half of the whole num- ber of defective boilers became so on account of incrustation and deposit of sediment; and, strange as it may seem, there were forty per cent. more dan- gerous cases from the deposit of sediment than from incrustation and scale. The first duty of an engineer or fireman when he enters his boiler-room in the morning is to try the boiler gauge-cocks and ascertain if there is a suff- cient supply of water. Many boilers have been badly injured from neglect of this precaution. Fires are often replenished, and when well started, attention is directed to the water in the boiler. If from any cause during the night the water has escaped, the result may be a burned sheet, or probably still more serious injury. Too much reliance should never be placed on self-acting apparatus, such as gongs, floats, steam or alarm whistles, for regulating the height of the water in steam-boilers, as, even if they act with certainty, they provide only against one or two contingencies, while the dangers to which steam-boilers are exposed are numerous. THE STEAM-BOILER. 241 The glass water-gauge, though one of the sim- plest, most beautiful, and useful attachments of the steam-boiler, should not be relied upon altogether to show the level of the water in the boiler. The gauge-cocks should be kept clean and in con- stant use, as they furnish the most reliable means of ascertaining the height of the water in a steam-boiler. The furnace door should never be allowed to remain open longer than is sufficient to clean and replenish the fire, as the contraction of the tubes and flues, induced by the cooling down of the furnace, has a very mischievous effect on all parts of the boiler exposed to the cold draught. The feed-water should be sent into the boiler as hot as possible, as, if it be forced in at a low tempera- ture, it will impinge on that portion of the boiler with which it comes in contact, and, as a result of the continual expansion and contraction induced by the varying temperature of the water, the boiler is liable to crack and become leaky. If, from neglect or any other cause, the water in the boiler should become dangerously low, the fire- doors and damper should be immediately thrown open, for the purpose of admitting the cold air to the heated plates, and the fire withdrawn as soon as pos- sible. Under such circumstances no attempt should be made to introduce cold water into the boiler, or disturb the safety-valve, as either might be attended with disastrous results. PAS oh Q 249 USE AND ABUSE OF The safety-valve should always be moved before the fire is started to get up steam, for the purpose of ascertaining if it is in good working order. It should also be raised whenever the boiler is being filled with cold water in order to allow the air to escape, as air has a tendency to retard the influx of the water, and also to occupy the steam-room when steam is raised. Air also interferes with the uniform expansion of the boiler. All new boilers should be thoroughly examined before being filled with water, to ascertain if there are any tools, wood, lamps, greasy waste, etc., left behind by the boiler-makers, that would be liable to be carried into connections or cause the boiler to foam. In getting up steam in boilers just filled with cold water, or that have been out of use for some time, the fire should be allowed to burn moderately at first, in order to admit of the slow and uniform expansion of all parts of the boiler; as, when the fire is allowed to burn rapidly from the first start, some parts become expanded to their utmost limits, while others are as yet nearly cold, thereby subjecting the boiler to fear- ful strains, induced by unequal expansion and con- traction, which frequently results in leakage, frac- ture, and sagging of the shell or flues. When boilers are laid up, or out of use, even if it be for a few days, they should be opened, cleaned, and thoroughly examined, to ascertain if any of the stays or braces have become loose, slack, or disconnected. | THE STEAM-BOILER. 243 ' Before being closed up, all gaskets for man- and hand-holes, and grummets for mud-holes, should be painted with a coating of black lead and tallow, to protect their seats from deterioration induced by the chemical action of the sulphur in the gum-pack- ing, now so universally used for the joints of steam- boilers. When the weight is once fixed on the lever of a safety-valve, at the right point to retain the safe working pressure, the extra length of the lever should be cut off. The feed-supply and the firing should be as steady and as regular as possible, as frequent and extreme alterations of temperature, especially with boilers carrying a high pressure, or irregularities of any kind, have a very injurious effect. Ashes should never be allowed to accumulate around the water-legs of fire-box boilers, or the water-bottom of any boiler, as wet ashes, like any other lye, corrodes, and eventually destroys the iron. Boiler-flues should never be allowed to become choked with ashes, nor the shells to become coated with soot, as it very much impairs the efficiency of the heating surface and induces a wasteful consump- tion of fuel. The flues and tubes of boilers should be swept out at least once a week. This is a very im- portant object in point of economy, as, when the flues become choked with ashes, it requires an extra ex- penditure of fuel to generate the necessary quantity 244 USE AND ABUSE OF of steam. Care and attention to little matters in managing steam-boiler fires will not only add to the working age of a boiler, but save materially in the consumption of fuel. Boilers should never be filled with cold water while they are hot, as it causes contraction of the seams and stays, often inducing fracture of stays or leakage in theseams and tubes. The tubes of boilers being generally of thinner material than the shell, cool and contract sooner. For this reason the boiler should never be filled with cold water while the tubes are hot. When two or more boilers are connected by feed- pipes, the stop-valves on each should be shut off when not working, as the water is liable to escape from one to the other, on account of variation in the pressures ; and as a consequence, when the water in one is up to, or even above, the proper level, the tubes or flues in the other are very often destitute of water. When, in consequence of leakage, accumulations of salt occur in the flues or tubes of marine-boilers, they should be removed as soon as possible and the tubes thoroughly swept, or, if need be, bored out with a flue-scraper; otherwise the parts covered with the accumulation will be apt to be burned through. In some cases it is necessary to direct a steam-jet on the place affected for the purpose of softening the deposit. | When flues become so leaky that it is impossible THE STEAM-BOILER. 245 to make them tight in the tube-sheet by calking, this object can be effected by cast- or wrought-iron ferrules or expanders driven into the end of the tube. This arrangement, however, is only an alternative, as it interferes with the free escape of the gases from the furnace and diminishes the draught. One of the most common causes of deterioration in steam-boilers, and also of leakage of the seams and under side, and at the junctions of the tubes and tube-sheets, is the reckless practice of blowing out the boiler while still hot and filling it again with cold water. Under such circumstances, the contrac- tion of the crown-sheet, tube-sheets, and tubes is so rapid and unequal, that, if persisted in, the result is the ruin of the boiler. When an engine is stopped, if the steam should increase to an excessive pressure, the safety-valve should not be moved, as any sudden release of the steam might be attended with risk: it is better to open the furnace door, cover the fire with fresh fuel and turn on the feed-water ; this will have a tendency to lower the temperature and keep up the circulation in the boiler, so essential to safety when the steam is shut off and a hot fire in the furnace. Many boilers have exploded just as the engine was starting, after having stood still for some time; this arose, doubtless, from the fact that the plates directly around and in contact with the fire became over- heated in consequence of the circulation becoming 21 * 246 USE AND ABUSE OF enfeebled or entirely suspended after the steam was shut off. As soon as the engine was started and the pressure lessened, the water on the surface of the over-heated plates flashed into steam of tremendous elastic force. When boilers are to be cleaned they should be allowed to stand for several hours and cool before the water is run out; the deposit of mud and scale will then be found to be quite soft, and can be easily removed or washed out with a hose from all accessi- ble parts. There is a very erroneous impression ex- isting among engineers and steam-users, that blowing out a boiler under a high pressure has a tendency to remove the mud or deposit; this, however, is a mistake, as the contraction of the different parts of the boiler, induced by so sudden changes of tempera- ture, has a tendency to induce leakage of the seams and round the rivets and ends of the tubes. It is a very general impression among engineers and firemen, and receives encouragement from those who sell nostrums for the prevention and removal of scale, that so long as the mud or deposit is retained in the soft or slushy state, it can do the boiler no harm. ‘This is undoubtedly a mistake, as it retards the escape of the heat from the fire to-the water, in- ducing over-heating, which is generally followed by cracking and blistering of the plates and leaking at the seams. It is not uncommon in factories to have two THE STEAM-BOILER. 247 boilers for the same engine, in order that one may be out of use while the other is working; but, while this is an accommodation, it is not always economy, as boilers wear out faster when not in use, by oxidiz- ing and corroding, than if moderately worked. It will be found more economical to work with extra boiler room than to have one or more standing idle, as it will tend to prevent priming; besides, the fur- naces will be more economically worked with a thick fire than with a thin one, and more of the heat will be absorbed by allowing it to accumulate, thereby maintaining a high temperature in the furnace with slow combustion. Never neglect to blow out, examine, and clean boilers when solvents are used to prevent and remove scale; because boilers under such circumstances re- quire as much, if not more, care than if no solvent or compound is used, as all that can be accomplished at best by such agents, is to loosen and throw down the scale, which if not removed will be apt to form into a hard conglomerate on the bottom of the boiler, preventing the water from coming in contact with the iron; the result is, the plates are burnt through and the boiler permanently ruined. T is a matter of regret that, too often, fire- men and engineers are laggards in the issues Of that real intelligence which ought to be carried out as effective traits of char- acter, indispensable to the credit of their profession. Too often a loose indifference to correct rules ts displayed by them, which shows that they have failed to perceive their own advantages. 248 THE STEAM-BOILER. 249 INSTRUCTIONS FOR FIRING. In estimating the relative merits of different steam-engines, it is generally 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 coal on a fire and keep*his bars clean, must be as good as any other, however well qualified. But this conclu- sion is totally erroneous, as it is within the experience of nearly every engineer and steam-user, that many engines now in operation throughout the country consume twice as much ftel, per horse-power, as is required for those that are more economically man- aged. The use of a more improved class of steam- engines involves the necessity of employing more skilful and careful attendants; not that the work is more difficult, as less coal has to be thrown into the furnace, but because a careless or unskilful fireman can counteract all the ingenuity displayed in the improvement, construction, and management of the engine. Consequently, every engineer should be required to prepare himself for the duties of his pro- fession by commencing as a fireman; otherwise, he cannot. be expected to be able to instruct his fireman in the manner of firing best calculated to insure the most satisfactory and economical results. There have not been, heretofore, that attention 250 USE AND ABUSE OF and thought devoted to the examination of the sub- ject of the economy of fuel which the magnitude of the interest involved, and its importance, in a na- tional point of view, render it worthy of. The saving of one pound of water per horse-power per hour for ten hours a day, in an engine of 100 horse- power, assuming that the boiler evaporates 7 pounds of water per pound of coal, would make a saving of 1000 pounds of water per day, which would require the consumption of 143 pounds of coal — 225 tons a year — the cost of which would be, at the ordinary price of coal, over $125. The methods most in vogue for the consumption of all kinds of fuel are those which gradually de- veloped themselves, as necessity dictated, to the un- tutored intellect of uncultivated men, but which, however creditable to the men that devised them, inasmuch as they availed themselves of all the sources of information within their reach, are never- theless a reproach to the more advanced knowledge of physical and mechanical science enjoyed by the present generation. Even with the best coal and most careful firing, a quantity of the coal falls through the fire-bars either as unburnt coal or ashes. Another portion goes up the chimney, unconsumed, in the form of smoke and soot; and a further quantity, half consumed, in the form of carbonic oxide. The loss from these causes may amount to from two to twenty per cent. It all THE STEAM-BOILER. 251 arises from wrongly constructed furnaces and bad firing, and can nearly all be avoided. Most coal con- tains a greater or less quantity of moisture, and the evaporation of this moisture causes the first loss of heat. Radiation from the furnace causes a further loss. But the great causes of loss are the admission into the furnace of a large quantity of useless air and inert gases, and the escape of these, with the actual products of combustion, up the chimney at a very much higher temperature than that at which they entered the furnace. Air is composed of about one-third oxygen and two-thirds nitrogen. The oxygen only is required to effect the combustion of the fuel, and the useless nitrogen merely abstracts heat from the combustibles and lowers the temperature of the furnace. About 12 pounds of air contain sufficient oxygen to effect the combustion of 1 pound of coal; but, owing to the difficulty of bringing the carbon into contact with the oygen, the quantity actually required to pass through the furnace is from 18 to 24 pounds of air per pound of coal burnt. The surplus air passes out unburnt, and its presence in the furnace lowers the temperature there and abstracts a portion of the heat generated. As the whole of the air enters the furnace at about 60° Fah., and the unconsumed air and products of combustion leave the flues at from 400° Fah. to 800° Fah., the total loss from these causes is from 20 to 50 per cent. Each pound of 252 USE AND ABUSE OF good coal burnt is theoretically capable of evapo- rating about 14 pounds of water. In practice, under the most favorable circumstances, it evaporates but from 7 to 9, and in ordinary practice from 4 to 6. There are difficulties in the way of abstracting all the heat from the furnace gases. First, because, with natural or chimney draught, the gases require to pass into the chimney at not less than 500° Fah., in order to maintain the draught ; and, secondly, because the transmission of heat from the gases to the water, when the difference of their temperatures is small, is so slow that an enormous extension of the surface in contact with them becomes necessary in order to effect it. But by having energetic combustion and a high temperature in the furnace, the quantity of air actually required may be much reduced. By suitable arrangements for admitting air and feeding coal into the furnace, the proportions of each may be suitably adjusted to each other; and by a liberal allowance of properly disposed heating-surface, the temperature of the gases may be reduced to that simply necessary to produce a natural draught, or to about 400° Fah. or less, in a furnace where the draught is obtained from a steam-jet or fan. Before starting a fresh fire, any dust, ashes, or cinders that may have remained in the furnace after the fire was drawn, should be removed and the sur- face of the bars made perfectly clean and level ; then a thin layer of fresh coal should be scattered over THE STEAM-BOILER. 258 the grates for the purpose of protecting them from the extreme heat of the fresh fire, as the coal so scattered will absorb the heat that would otherwise be transmitted to the grates, and cause them to spring or warp. The fresh fuel will also cause the fire to burn more moderately, which is an object of great importance when boilers are cold. Most of the kindling, whether light wood, shavings, oily-waste, or paper, should’ be placed in the front end of the grates, near the furnace door, and then covered with a uniform layer of wood. ‘This is a necessary pre- caution, as, when the fuel fails to ignite at the front at first, it generally takes a long time before the fire buras through. When a boiler is of sufficient capacity to generate the necessary amount of steam, without urging the fires, it will be found most advantageous to carry a thick bed of coal on grates, as, when the coal can be burned in large quantities and with a moderate draught, the heat is more generally utilized than if the coal is burned in small quantities and with a sharp draught. For stationary boilers, the fuel should not be less than from 3 to 4 inches thick on the grate; for. marine or locomotive boilers, if anthracite coal be used, from 5 to 6; if bituminous, from 6 to 8 inches. Of course, the thickness of the fire must be governed by the character of the fuel and quantity of steam required. When the coal is in large lumps, so that the 22 254 USE AND ABUSE OF space between them is considerable, the depth may be greater than where the coal is small and lies com- pactly; and where the draught is very strong, so that the air passes with great velocity over and through the fuel, there is not time for the carbonic acid to combine with and carry off the products of combustion, and consequently a bed of greater depth may with propriety be used. When very large coal is used, it will be found of advantage to mix it with some small ‘coal, particularly when the draught is strong, as such an arrangement forms a resisting barrier to the currents of cold air that would other- wise pass through the interstices between the lumps, and render the combustion more perfect. When an increased quantity of steam is wanted, the average thickness or quantity of fuel on the grate must not be increased, but rather di:ainished, and supplied in smaller quantities and more frequently. As soon, however, as the supply of steam exceeds the demand, the coal may again be supplied in larger quantities at a time. When it becomes necessary to replenish the fire, it should be done as quickly as possible, as, when the damper and the fire-door are both open at the same time, the current of cold air passing through the furnace above the fuel not only reduces the temperature in the furnace, but has a tendency to injure the boiler. There should in all cases be ample fire i the furnace, an extra quantity of water in the boiler, and a ae eee, . THE STEAM-BOILER. 25d a full head of steam, before any attempt is made to clean the fire. Then the damper should be opened to its full extent, in order that the heated gases and dust may pass into the flue; and if there be more than one fire, one only should be cleaned at a time, and allowed to become thoroughly kindled before the next one is cleaned. The fire should never be allowed to become low for the purpose of making it more easy to clean, as, in consequence of the small quantity of fire in the furnace after cleaning, the combustion is cheeked, the temperature of the fur- nace lowered, and consequently a serious loss of fuel incurred. It is always best to have a good fire in the furnace before commencing to clean; then close the damper and open the furnace door for a few minutes, in order to take the white glare off the fire before com- mencing to clean it. The damper should then be reopened to its full extent and all the live fire pushed back to the bridge, without disturbing any of the ashes or cinders. The latter should then be drawn out, and the fire that was pushed back drawn for- ward, and the ashes and cinders that remain near the bridge removed. The fire should then be dis- tributed evenly over the grate, all the cinders and clinkers that remain picked out, and the fire covered with a thin layer of fresh coal, care being taken to waste none of the combustible fuel. The fire should never be disturbed so long as any 256 USE AND ABUSE OF light shines through the grate into the ash-pit, unless the boiler fails to furnish the necessary amount of steam. Even then it is better, if anthracite coal be the fuel, to shed out the ashes from the bottom through the grate with a thin, hooked poker. But, if bituminous coal be used, it requires frequent breaking up, in order to allow the air to intensify the combus- tion. When broken up, it should always be pushed back toward the bridge, fresh fuel supplied in the front,and allowed to coke. The smaller the quantity supplied at a time, and the more attention paid to its distribution and regulation, the more perfect will be the combustion, and the more intense the heat. if, from neglect or any other cause, the fire should become low or the grate partly stripped, it should not be poked or disturbed, as that would have a tendency to put it entirely out; but wood, shavings, - sawdust, greasy-waste, or some other combustible substance, should be thrown on the bare places, and after being covered with a thin layer of coal, the damper opened to its full extent. The regulation of the draught should receive particular attention, as air costs nothing, while fuel is quite expensive. — Therefore none of the latter should be allowed to pass out of the furnace without being fully utilized. The ash-pit and front of the furnace should at all times be kept free from dirt, ashes, and cinders, as such accumulations have not only the effect of dimin- ishing the cubic contents of the space under the fur- ee eT Te eee ae THE STEAM-BOILER. 257 nace, but also of obstructing the free current of air through the grate-bars, so essential to the perfect combustion of the fuel. “ It is a well-known fact, that much of the waste attributed to the steam-engine occurs in the furnace, and may be summed up as follows: Waste of un- burnt fuel in the solid state; waste of unburnt fuel in the gaseous or smoky state; waste by external radiation and conduction; waste by the excess of heat which escapes by the chimney over. that re- quired for the draught. These sources of waste give rise to excessive losses, which perfect arrangement and good management may tend to avoid; and if the arrangement and proportion of the boiler are good, the losses which occur in the consumption of fuel may be attributed, in a great measure, to the ignorance, inattention, or carelessness of the fireman. Clean grate-bars, with an even distribution of the fuel in the furnace, the exercise of judgment in the quantity of air admitted, and the regulation of the draught, are the main points to be attended to; and although they require the exercise of skill and intel- ligence, they cannot be said to involve an unreason- able amount of either labor or vigilance. When it becomes necessary to supply fuel to a boiler furnace, or to clean, slice, or poke the fire, it should be done with decision, quickness, and en- ergy, as, when the furnace door and damper are open at the same time, the cold currents of air passing in 22 * BR. 258 USE AND ABUSE OF above the fuel have a tendency not only to lower the temperature of the furnace, but to impinge on the parts of the boiler most exposed to the fire, which induce contraction, leakage, and permanent injury. DAMPERS. In the foregoing chapters such articles and at- tachments as have for their object the control and regulation of the water, the designation of the steam pressure, and the cleaning of boilers, have been con- sidered. It may not now be out of place to call attention to appliances for regulating the draught in furnaces, flues, and chimneys, which, as now em- ployed, are few and simple, consisting either of a cir- cular plate, which swings in a round flue, or a square. plate sliding in an iron frame. The importance of / efficient dampers has never received due consideration either from engineers or steam-users, when we con- sider how largely they contribute to the economy of fuel, by retarding the combustion which would gener- ate steam in excess of that needed, and also by pre- venting the cold air from escaping into the flues when the boiler is not in use, thereby lowering the temperature of the boiler and its surroundings, and involving the expenditure of an extra quantity of fuel when steam is raised. The damper illustrated on page 339 is one of the most simple and efficient — devices ever invented for the regulation of draughts in the furnaces of steam-boilers. Ko one who destres to be proficient in his Ci’ art will rest satisfied with a knowledge of the mere routine duties required. It is not enough to know that certain results are pro- duced from certain causes; this we may learn from mere experience. But, in order to become really intelligent, we must So further, and learn why the cawses produce the results, so that, in an emergency, other means may be swbstituted to accomplish the desired ends. 259 260 USE AND ABUSE OF STEAM-BOILER INSPECTION. It is asserted, on reliable authority, that the pro- portion of boiler explosions and ruptures, as com- pared with the number of boilers in use, exceeds the number of fires in buildings as compared with the number of buildings in the country. Tt is estimated that there are upwards of 100,000 steam-boilers in use in this country ; the number of explosions annu- ally is from 125 to 150, but when to these are added the ruptures, collapsed flues, ripped seams, etc., the number of disasters is increased to 900 or 1000, making one per cent. of the whole number in the country damaged more or less annually. The use of steam-power is increasing the world over, and it will continue to increase until some new motor, more effective and less expensive, is discov- ered. Therefore, intelligent and thorough boiler in- spection is one of the imperative necessities of the age. The manufacturer or steam-user, from a press of business or a want of that practical knowledge which is only attained in any pursuit by close study and observation, is unable to attend or give direc- tions in all the details involved in the care and man- agement of his steam-boilers. For a very small consideration, he can avail himself of the advantages to be derived from the inspection and insurance of steam-boilers, by placing his boilers under the care of responsible and reliable parties, who will do THE STEAM-BOILER. 261 everything that can be done to insure safety. The experience of the past in the care and manage- ment of steam-boilers has shown the necessity of such a system, as it not only gives additional se- curity from the effects of boiler explosions, but also refutes the false and absurd theories which have tended to divert the attention of engineers and owners of steam-boilers from that watchfulness so essential to their care and management, by inducing the belief that no amount of care on their part will avail against certain mysterious agents at work within their boilers. Another advantage of intelligent and practical steam-boiler inspection is, that it gives the engineer an opportunity to inform himself on many points of vital importance, by conversing with one who, from making a special business of boiler-inspections, has become thoroughly versed in all matters pertaining to boilers and their attachments; consequently, every engineer and fireman should afford boiler-inspectors every facility to make a thorough examination of the boilers in their charge. They should give them all the information and facts relating to the same, as it may not only be the means of saving their own lives, but of many others, as well as much valuable. property. It is the duty of all engineers, steam- users, and those who take an interest in the lives and property of their fellow-man, to encourage care- ful, thorough, and intelligent steam-boiler inspection, 262 USE AND ABUSE OF which, to be efficient, must have a pecuniary interest involved in its operations, as those who sustain no loss, either of time, means, or salary, are apt to become derelict of duty. RULES FOR FINDING THE QUANTITY OF WATER WHICH BOILERS AND OTHER CYLINDRICAL VESSELS ARE CAPABLE OF CONTAINING. Rule for Cylinder Boilers.— Multiply the area of the head in inches by the length in inches, and divide the product by 1728; the quotient will be the number of cubic feet of water the boiler will contain. EXAMPLE. Diameter of head, 36 inches. Area il ie a OL ue te Lae Length of boiler, 20 feet, or 240 inches. 1017.87 ime nk 4071480 _ 208574 1728)244288.80 141.87 cubic feet. Rule for Flue Boilers. — Multiply the area of head in inches by the length of the shell in inches; mul- tiply the combined area of the flues in inches by their length in inches; subtract this product from the first, and divide the remainder by 1728; the THE STEAM-BOILER. 2638 quotient will be the number of cubic feet of water which the boiler will contain. Rule.— To find the Requisite Quantity of Water for a Steam-boiler.—Add 15 to the pressure of steam per square inch; divide the sum by 18; multiply the quotient by .24; the product will be the quantity in U.S. gallons per minute for each horse-power. Rule.— To find the Required Height of a Column of Water to supply a Steam-boiler against any given Pressure of Steam.— Multiply the boiler pressure in pounds per square inch by 2.5; the product will be the required height in feet above the surface of the water in the boiler. Another Rule.—7o find the Requisite Quantity of Water for a Steam-boiler—When the number of pounds of coal consumed per hour can be ascer- - tained, divide it by 7.5, and the quotient will be the required quantity of water in cubic feet per hour. EFFECTS OF DIFFERENT KINDS OF FUEL ON STEAM-BOILERS, Anthracite coal is undoubtedly the most trying fuel on the parts of steam-boilers exposed to its direct action, but nevertheless it is less destructive to the whole structure than either coke, wood, or bituminous coal. This arises from the fact that it can be consumed in more uniform quantities, and offers better facilities for the regulation of the air 264 USE AND ABUSE OF than any other kind of fuel that might be used, as the grate-surface can be easily covered with a uni- form stratum necessitating the passage of the air | through it, which limits the quantity according to the thickness of the fuel on the grates, rendering the combustion more moderate and uniform. While, on the other hand, the combustion of coke, bituminous coal, and wood, is, at times, of the most fierce and energetic character; and, in consequence of the im- possibility of maintaining a uniform fire with these three last-named kinds of fuel, large quantities of air are admitted, which has a very deteriorating effect on all parts of the boiler, as they are continually exposed to the evils induced by extreme expansion | and contraction. BOILER MATERIALS. Boiler-making now holds an important place among the mechanical arts. Its progress has been aided chiefly by the enormous growth of the steam- engine, as the prime mover, and also by the increased facilities afforded for procuring suitable materials and by the improvements made in working them. In the early days of the steam-engine, boilers of copper and cast-iron were used for generating steam, but they were seldom subjected to a higher pressure than that of the atmosphere; but when pressures of 3 to 4, or even 7, atmospheres came into use cast-iron was THE STEAM- BOILER. 265 found to be unreliable and treacherous, for which reason it was discarded in favor of wrought-iron, which was not employed at first, in consequence of the difficulty found in working it and in making steam-tight joints. It has, however, of late years be- come the material employed to the almost entire ex- clusion of all others. In fact, it has been more ex- tensively used in the construction of steam-boilers, for the past thirty years, than any other material, doubtless on account of its great tensile strength, together with its ductility, power of bearing sudden and trying strains, and general trustworthy nature ; its moderate facilities of working, the ease with which it can be welded, riveted, patched, or mended ; its moderate first cost, etc. The first quality to be sought for in boiler mate- rial is strength. This does not necessarily imply the mere power to resist being torn asunder by a dead- weight, as in a testing-machine, but the quality to withstand, without injury, the varying shocks and ‘strains to which boilers are exposed. An inferior quality of plates cannot be relied upon to bear the ordeal of repeated heating and cooling, as they in- variably warp and twist, showing defects of. manu- facture; more especially in the process of cold- bending, when minute fractures often occur on the outer surface of the plates of stubborn or inferior qualities of iron. The defect most commonly revealed): in working 23 266 USE AND ABUSE OF boiler-plates is lamination. This defect arises from _ the imperfect welding of the several layers which make up the thickness of the plate, and is usually caused by interposed sand or cinder, which has not been expelled in hammering or rolling during the process of manufacture. This is more frequent in thick than in thin plates, and is sometimes very diffi. cult to detect in cold plate, although often discernible in the hot. It also often happens that plates, which are passed as quite sound, on careful external exam- ination, are found to be severely laminated when subjected to heating and hammering, and prove © totally unfit for use. Blisters are of a similar nature, and arise from the same cause as lamination. Sometimes they ap- pear as mere surface defects, and are of no conse- quence; but their appearance may be an indication of the want of care or skill in the making of the plate, and should always excite suspicion. It fre- quently happens that these defects pass undetected after the closest scrutiny and test by hammering, but disclose themselves soon after the boiler is set to work, especially if the plates be exposed to sudden variations of temperature. In the plates over the fire-grate of an externally-fired boiler such a blister may prove a very serious defect, and often necessi- tates the cutting out and replacement of the sheet. Inferior brands of iron will rapidly show unmis- takable signs of weakness, when placed under the THE STEAM-BOILER, 267 trying ordeal of bearing the alternate impingement of a fierce flame and currents of cold air. The rapid variations of temperature caused by the sudden and frequent openings of the furnace-door and leakage of cold air through the grate-bars will soon tell on any kind of iron, but more quickly on that of an inferior brand. | | Characteristics of Boiler Iron when Broken. — On breaking a plate or bar of wrought-iron the frac- ture presents an appearance by which the quality of the iron may, in some measure, be determined. ‘The fracture is designated on the one hand as fibrous, tough, silky, close-grained, etc., or, on the other hand, crystalline, coarse, open-grained, brittle, and cold- shut. When broken suddenly the best qualities of plate- and bar-iron exhibit a fine, close-grained, uni- formly crystalline fracture, even silky, of a. light, silvery color; the appearance in the harder descrip- tions approaching to that of steel. The appearance of indifferently refined and inferior qualities is coarser, usually of a darker color, more or less une- ven or open, exhibiting large facets, and approach- ing some descriptions of cast-iron. When broken gradually, good iron presents a well-drawn out close fibre, of light greenish hue, whilst inferior qualities give a shorter, more open and darker fibre. When good ductile iron is gradually torn asunder it draws out or stretches to a considerable extent, causing a diminution of sectional area at the frac- 268 USE AND ABUSE OF tured part, which should always be compared with the original sectional area of the specimen in judg- ing of the quality. An inferior bar or plate may bear as great a tensile strain as a similar specimen of superior quality; but, on comparing their frac- tured areas, it will generally appear that the latter has been drawn out considerably, whilst the inferior specimen, having stretched but little, has not sensi- bly diminished at the fracture. This is owing to the fact that good ductile iron is so much more trust- worthy than badly refined, when sudden strains occur. The one will stretch, while the other will snap. It is also a well-known fact that wrought- iron changes from fibrous to crystalline after en- during long-continued cold hammering, vibration, tension, jarring, and other strains, after long ex- posure to the influence of heat, or alternate expan- sion and contraction, whenever it has been used for the plates of a boiler-furnace. Even the very best plates, after from ten to twenty years’ use in a boiler, have frequently been found to break without stretching, at the same time displaying a crystalline fracture. It has been said that this shows that a change has taken place in the nature of the material, and that, from being fibrous and tough, it has, by some un- explained cause, become crystallized and brittle, or that it has lost its nature in consequence of the treat- ment it has undergone, whatever that may have been. THE STEAM-BOILER, 269 There is no doubt that the strains and other causes above mentioned have a tendency to make good iron become brittle and liable to snap suddenly under the same treatment that would originally have torn it, gradually, and to this extent a change is produced in its nature. This snapping, and not the fatigue of the metal, is however the direct cause of the crys- talline fracture, which is but a necessary consequence of the suddenness of the breaking, and not a property of the iron itself. To say it snaps readily because it has become crystalline is to confound the cause with the effect. It is erroneous to say the fibrous nature has passed out of the iron, for its ductility can, to some extent at least, be restored, in most cases, by simply heating to a bright red, and slowly cooling the iron, or, failing that, by hammering or rolling it while hot. By heating to redness and suddenly cooling a piece of wrought-iron, it will become liable to snap, producing the same effect as cold hammer- ing. The explanation of this is not clear, and it may be owing to the loosening of the crystals, into which the composition of the material ultimately resolves itself. To this cause may also be attributed the same tendency to snap after long-continued jar- ring, or alternate expansion and contraction. It may be asserted, without fear of contradiction, that all boiler-plate worthy of the name is fibrous; whether its hardness makes it liable to snap, and therefore appear crystalline, depends on its original 23 * 270 USE AND ABUSE OF character and the treatment it has undergone. No fine iron can, however, by any treatment, except burning, be made to appear coarse, and the fibres of the poorer descriptions of iron cannot, without re- fining, be made to appear fine and close-grained. It is from a want of knowledge of the above facts that false opinions are so often expressed respecting the qualities of boiler-plates. It is no unusual thing to find intelligent mechan- ics and boiler-makers expressing their opinions at coroners’ inquests on the quality of the iron in exploded boilers, without anything to base their opinions on except the load per square inch required to tear the plates asunder; they seem to forget that if the boiler be an old one, that the age, the position in the boiler in which the rent has taken place, the amount of strain to which it has been exposed, and all the circumstances connected with the occurrence, should be known in order to decide understandingly as to the quality of the iron. It has been shown in numerous instances that good ductile iron can be made to appear crystalline when pulled asunder in the testing-machine, by confining the minimum sec- tional area where fracture will occur to one point or to a very short length. The general conclusions, with regard to boiler material, which may be regarded as established from experiments, observation, and practice, thus far seem to be — 1st. That the laws of resistance of the parts THE STEAM-BOILER. 271 of boilers to the internal pressure are sufficiently well established. 2d. It is of the utmost importance that the materials employed should be of the best quality as regards strength and durability ; and as there are but few manufacturers of boiler-plates, the inspection of materials, especially boiler-plates, should be made by competent persons appointed for that purpose, at the place of manufacture, which inspection should extend to the qualities of ores and the process of manufacture; the required stamps, brands, or certifi- cates being put on or authorized by the inspectors in person. There is much greater certainty of securing the best materials by an inspection of the process of working and the raw materials employed, than by an inspection of plates after they have been sent to market, when, judging from all external appearances, good and bad plates are not easily distinguished. Practical limits to the thickness of boiler-plates. The proper strength of boilers, in order to enable them to withstand with safety the required pressure of the steam, is a matter of much importance as re- gards both life and property ; and the responsibility of the proprietors and constructors of boilers is of so grave a character as to justify the devotion of a much larger space to this subject than is convenient in this work. The principles on which the strength of all boilers, of whatever material, depend, may be expressed in a very few words —the strength being directly as the thickness of the metal, and inversely as the diameter of the boiler. 972 USE AND ABUSE OF So long as the quality of boiler iron remains as it is at present, the thickness of the plate may be prac- tically determined within exceedingly narrow limits, as a good boiler must be constructed of plate ranging in thickness from not less than one-fourth to not greater than one-half an inch, as anything less than the former cannot be properly calked, and any thickness greater than the latter is difficult to rivet without the aid of machinery. A thickness of three- eighths seems to have become the standard thickness for all diameters of boilers intended to sustain a high pressure ; this, perhaps, arises from the fact that boiler-makers seem to be better acquainted with the practical limit to the strength of that thickness, because it has, of late years, been used more than any other; nevertheless, for steel, of some of the higher grades of American plate, a less thickness will suffice for the same pressure. STEEL. As steel is likely to be universally adopted asa material for boiler-shells, it is unnecessary to look forward to any further progress in the direction of obtaining a stronger material. Therefore, any effort to increase the strength of boilers should be directed to the selection of the best material, and to the most practical methods of disposing of it. Steel seems to meet the demand for the new mate- THE STEAM-BOILER., 2738 rial, and has been able, under very varying cir- cumstances, within the past seven or eight years, to establish its superiority over iron or copper. In comparing the properties of steel and iron plates, there can be no doubt that the processes employed in the production of .cast-steel are im- mensely superior to those employed in the manu- facture of wrought-iron, for insuring a uniform texture in the material. Cast-steel plates, made from a fluid mass run into a single ingot, and when well worked under the hammer, are likely to be perfectly homogeneous and free from the imperfect welds and internal defects caused by the presence of cinder and slag, either of which is frequently found even in the best-puddled iron, which, being built up of numerous small pieces, all more or less properly welded together, is entirely dependent upon the skill and care exercised in its production for its homo- geneity and freedom from lamination, blisters, and other internal defects. It was probably the high degree of tenacity and ductility, exhibited by tool- and spring-steel, that first drew attention to the advantages offered by this material for the construction of steam-boilers. Its high price, however, long stood in the way of its being largely adopted; and this obstacle was only removed by the introduction of new methods of manufacture, which can as yet be termed improve- ments only with respect to their commercial success, 8 274 USE AND ABUSE OF and not as affecting the quality of the material. There can be little doubt that the adoption of steel for boiler-plates has been retarded by the want of knowledge of its properties, and the consequent diffi- culty sometimes met with in working it. The result: of this is a disposition on the part of the great major- "ity of boiler-makers to avoid using it as much as possible. It has been found by experiment with different qualities of steel-plates that. toughness is incompati- ble with great tensile strength, and these two quali- ties may be considered as being in the inverse ratio to each other. If it becomes necessary to have steel with a tensile strength of from 90,000 to 100,000 pounds, it will be found to be hard and brittle,.and, therefore, not adapted for boiler-plates. In order to insure freedom from brittleness, a tensile strength of from 60,000 to 80,000 pounds is the maximum that can be allowed. The high degree of tensile strength exhibited by steel-plates allows the use, with safety, of this material thinner than either iron or copper, thus reducing the weight, and rendering the difference iu first cost of material an item of less magnitude than is usually supposed. Besides the weight saved by using steel — often a most impor- tant consideration — it may be urged that the thinner plates will conduct the heat more rapidly, and give a correspondingly superior evaporative efficiency. This superiority is not, strictly speaking, in. propor- THE STEAM-BOILER. 275 tion to the reduction of thickness, since the relative conducting powers of steel and iron are about 244 and 218. Then the density and perfect homogeneity of steel render it nearly impervious to the action of sulphur and other foreign ingredients existing in coal and water, which have proved so destructive to iron and copper. Effect of Punching on Steel-plates.— One of the principal results obtained, both from experiments and experience of the material in actual riveted work, is that steel-plates of average suitable quality are more injured than wrought-iron plates by punch- ing. It is chiefly ship-builders to whom _ boiler- makers are indebted for exact experimental knowl- edge. on the behavior of steel-plates in the process of punching. STRENGTH OF IRON BOILER-PLATE. Although there is great variation in the tensile | strength of rolled iron boiler-plate, since that of good plate will average about 50,000 pounds per square | inch, if the strain is applied in the direction of the “grain” or the fibres of the iron (or the direction in which it has been rolled), and about ten per cent. less if the strain is applied crosswise of the grain, it has, however, been found by experiment that, when a tensile strain is applied to a bar of iron or other material, it is stretched a certain amount in 276 USE AND ABUSE OF proportion to the length of the bar and to the degree of strain to which. it is subjected. It is found that if this strain does not exceed about one-fifth of that which would break the bar, it will recover its orig- inal length, or will contract after being stretched, when the strain is removed. The greatest strain which any material will bear, without being permanently stretched, is called its limit of elasticity; and so long as this is not ex- ceeded, no appreciable permanent elongation or “set” will be given to iron by any number of appli- eations of such strains or loads. If, however, the limit of elasticity be exceeded, the metal will be per- manently elongated, and this elongation will be in- creased by repeated applications of the strain, until finally the bar will break. At the same time, the character of the metal will be altered by the repeated application of strains greater than its elastic limit, and it will become brittle and less able to resist a sudden strain, and will ultimately break short off. It is, therefore, unsafe to subject iron, or, in fact, any other material, to strains greater than its elastic limit. This limit for iron boiler-plates may be taken at about one-fifth its breaking, or, as it is called, ultimate strength. It should be remembered, however, in this connec- tion, that it often happens that the steam pressure is not the greatest force the boiler must withstand, as sudden or unequal expansion and contraction are THE STEAM-BOILER. Qe probably more destructive, to locomotive boilers especially, than the pressure of the steam. , The manufacture of boiler-plates is carried on very extensively in the United States, especially in Pennsylvania. American iron is naturally stronger and tougher than the English, bearing an average tensile strain of from 60,000 to 70,000 pounds per square inch, while the best Yorkshire iron bears only about 56,000 pounds to a square inch, and the Staffordshire about 44,800 pounds. The mean ten- sile strength of American cast-iron has been deter- mined with considerable care by means of experi- ments conducted for the United States Government. Major Wade, of the U. 8S. Ordnance Corps, found that the mean tensile strength of American cast-iron was 31,829 pounds per square inch of section ; while the tensile strength of the English cast-iron, as determined by Mr. Hodgkinson for the railway companies, is very much inferior to this — being but 19,484 pounds to the square inch. DEFINITIONS AS APPLIED TO BOILERS AND BOILER MATERIALS. Cohesion is that quality of the particles of a body which causes them to adhere to each other, and to resist being torn apart. Curvilinear Seams.— The curvilinear seams of a boiler are those around the circumference. 24 278 USE AND ABUSE OF Elasticity is that quality which enables a body te return to its original form after having been dis- torted, or stretched, by some external force. Internal Radius.— The internal radius is 1 of the diameter less the thickness of the iron. To find the internal radius of a boiler, take 4 of the external diameter and subtract the thickness of the iron. Limit of Elasticity.— The extent to which any material may be stretched without receiving a per- manent “ set.” Longitudinal Seams.— The seams which are par- allel. to the length of a boiler are called the Jongi- tudinal seams. Strength is the resistance which a body opposes to a disintegration or separation of its parts. Tensile strength is the absolute resistance which a body makes to being torn apart by two forces acting in opposite directions. Crushing strength is the resistance which a body opposes to being battered or flattened down by any weight placed upon it. Transverse strength is the resistance to bending, or flexure, as it is called. Torsional strength is the resistance which a body offers to any external force which attempts to twist it round. Detrusive strength is the resistance which a body offers ‘to being clipped or shorn into two parts by such instruments as shears or scissors. —- < THE STEAM-BOILER. 279 Resilience, or toughness, is another form of the quality of strength; it indicates that a body will manifest a certain degree of flexibility before it can be broken; hence, that body which bends or yields most at the time of fracture is the toughest. Working Strength.— The term “working strength” implies a certain reduction made in the estimate of the strength of materials, so that, when the instrument or machine is put to use, it may be capable of resisting a greater strain than it is ex- pected on the average to sustain. Safe Working Pressure, or Safe Load.—The safe working pressure of steam-boilers is generally taken as 1 of the bursting pressure, whatever that may be. Strain in the direction of the grain, means strain in the direction in which the iron has been rolled; and in the process of manufacturing boiler-plates, the direction in which the fibres of the iron are stretched as it passes between the rolls. ; , Stress.—By the term “stress” is meant the force which acts directly upon the particles of any mate- rial to separate them. — There is another property of boiler materials which has been named “fatigue of metals.” It refers to that ultimate tendency to wear out, from which material and inanimatesubstances seem no more exempt than living creatures. It may be explained, perhaps, by the “stretch,” and consequent weaken- ing, which experiments establish as a quality of the ~ 280 USE AND ABUSE OF toughest iron. The following are the results of a series of experiments made by Captain Rodman, at the United States Arsenal at Watertown, upon the iron manufactured by a well-known firm in Balti- more. A square inch of the best flange iron was subjected to the various strains mentioned, with such results, as to temporary and permanent stretch, as are shown in the annexed columns :— : Temp’y Stretch. |Permanent Stretch. sca mia Sa gk poss of an inch. Pores of an inch. O00 ba... sattare oeek: 20 0 HGO00 FOL oiled 41 1 CATO ie Siar perk se 57 1 BB ODO. craig bin cates 76 3 DS H60' aS 100 7 ROD, cg Sire ci 537 408 BODO) 8 heres dees ag J8RS 1661 Bp oom ere alae 4000 It will be seen from the above table that the first essay, by means of a strain of 5,000 lbs., produced no permanent stretch in the bar; and that 10,000 Ibs. and 15,000 Ibs., respectively, only produced a permanent stretch of ;4°% of an inch, or about 4 of the temporary stretch. But in the next two strains of 20,000 and 25,000 lbs., the iron begins to show a great acceleration of the weakening process or in- crease of fatigue, for now the permanent strain has sprung up to ; of the entire stretch. In the two - THE STEAM-BOILER. 281 next items this acceleration is astounding, the perma- nent stretch being 3 of the whole upon 30,000 lbs., and ,% of the permanent stretch of 35,000 lbs. PUNCHED AND DRILLED HOLES FOR BOILER SEAMS, Punching rivet holes, according to Fairbairn’s experiments, is in itself a cause of weakness. Not only is the section of the plate in the line of the 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 disturb the molecular arrange- ment 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 lbs., and the lowest 43,805 lbs., per square inch ; but with the same plates, after punching, the strength per square inch varied between.45,743 lbs. and 36,606 lbs. The average of the two experiments, there- tore, showed a loss of 10,896 lbs. per square inch, due to the jar and strain of punching, in addition te the loss of section through the holes. In the process of punching, from a want of ac- curacy in laying off the holes, through ignorance * 282 USE AND ABUSE OF or neglect of workmen, the holes do not come opposite, sometimes half, their diameter; they are then drifted until the sheet is fractured, and the material partly destroyed.* This habit cannot be too much repre- hended, and the use of drift-pins, although consid- ered indispensable by many good boiler-makers, is productive of great evils. As a result, when the rivets are driven, it is almost impossible to make them fill the holes, and consequently an undue strain will come upon some of the rivets, while upon others there will be very little. In that case, there is danger of shearing off the rivet upon which the extra strain comes, inducing a strain upon the ad- joining holes, and thus starting a rupture, which will ultimately result in the destruction of the boiler. The usual arguments in favor of punching are a saving of from one-third to one-sixth of time and labor, as compared with drilling — a most conclusive argument with the manufacturer; but it is argued, on the other hand, that the positions of the holes marked off from the overlapping plate can be pre- served more faithfully with the drill than with the punch. This, doubtless, is a very strong argument, as it is well known that half-blind holes are the bane of boiler-making. But it must be understood that* the quality of the plate has an important influence on its manner of bearing the severe treatment it undergoes at the hands of the punching-machine. * See page 231. THE STEAM-BOILER, 283 Inferior and badly refined plates, being brittle, suffer toa much greater extent than those of better and -more ductile quality. In fact, punching a hole at the usual distance from the edge (oné diameter clear) in an inferior plate will often produce fracture. The violence done to the plate may be seen more clearly by considering the force requisite to punch it. It has been found by experiment that the resist- ance of a wrought-iron plate to punching is about the same as its resistance to tearing by a tensile strain. Recent experiments authorized by the United States Government, at the Washington Navy-Yard, establish the fact that drilled holes for boiler-seams are nineteen per cent. stronger than holes that are punched. From this it is obvious 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 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. _ Experiments on drilled and punched holes have shown conclusively that rivets in drilled holes, sub- ject to shearing strain, were about four per cent. weaker than rivets in punched holes, under similar & 284 USE AND ABUSE OF strain, and that the sharp edges of the drilled holes have a greater tendency to nip off the rivets than the rounded edges of the punched holes. In com- paring the strength of punched and drilled work, it was found, First, that drilled plates are 19 per cent. stronger than punched; second, that rivets are 4 per cent. stronger in punched holes than in drilled; third, that there is a difference of 15 per cent. in favor of drilled work. The following table shows the result of experi- ments on strips of boiler-iron cut from the same plate, two being punched and two drilled, with one inch holes, having a sectional area at the reduced part of 12 square inches. BREAKING WEIGHT IN TONS. Difference per cent. in favor of drilled. Difference in tons, Drilled bar. |Punched bar. Ist. | 304 | 26 | 41 | Lee 2d. 314 26 Bi 21 Mean. | 31 | 26 | 5 | 19 | The following are the results of experiments to test the difference in value between rivets in punched holes and similar rivets in drilled holes :— Experiment. 3 inch Rivets in Drilled Holes. First, single shear = 26 tons per square inch. double shear = 39.2 tons. THE STEAM-BOILER. 285 Second, single shear = 26.4 tons per square inch. double shear, experiment failed. & inch Rivets in Punched Holes. First, single shear = 27.2 tons per square inch. double shear = Second, single. shear = 26 tons per square ae double shear, experiment failed. It is generally assumed that plates of fair quality, having a tenacity of 42,000 pounds per square inch, cannot be relied upon to bear more than 32,000 to 34,000 pounds per square inch of section left be- tween holes in ordinary steam-tight riveted joints, which would be equivalent to about 24 and 20 per cent. loss of strength. This is about a maximum loss for hard plates of average equality ; but many soft plates do not suffer more than from 5 to 10 per cent. loss of strength; with the holes punched a whole diameter, clear of the edge, and at the second row of rivets, in double-riveting, do not suffer so much. The damage by punching diminishes as the distance of the hole from the edge increases; consequently, some boiler-makers, who prefer punching to drilling, have their plates cut about half an inch larger than their finished size, in order to keep the holes at a safe distance from the edge in punching; the surplus material being afterwards either chipped or planed off. 286 USE AND ABUSE OF Welding the seams of boilers would be of im- mense advantage, since the welded joint is nearly twice as strong as the riveted joint; and since twice as much steam pressure is exerted on the longi- tudinal seams of the cylinder of a boiler as on its circular seams, the right proportion of strength would be preserved by welding the former and rivet- ing the latter. The following advantages would be acquired by welding the seams of boilers :— Ist. It would cheapen the cost of construction, by saving much of the time occupied in riveting, and all that consumed in calking; 2d. The full strength | of the plates being preserved, a thinner material would suffice; 38d. Much higher pressure could be carried without increasing the weight of the boiler; 4th. There would be no double thickness of plate to pro- mote unequal expansion; 5th. Where the greatest strain would occur there would be no caps or joints, and consequently there would be no leakage. Rad 69s Bem SY SHOWING THE STRENGTH OF WELDED BOILER-PLATES. he dth nas fe | Broke | Broke Breaking Strength in Lbs. per in Square Inch. Ce Tested. | Weld. Solid. Least. | Greatest. Mean. | i A pond Pe a 5 8 f § 33,000 | 47,600 | 40,400. wae 4 md g 39,200 | 44,400 | 42,000 13 f 4 1 8 36,000 | 47,000 | 43,400 Total.) 23 | 33,000 | 47,600 | 40,600 THE STEAM-BOILER. 287 PATENT BOILERS. The patent boilers not described and illustrated in this book, are the “ Blanchard,” ‘‘ Lowe,” ‘“ How- ard,” “ Anderson,” “Kelly,” and “Lynde.” They belong to the same class as the Moorhouse, Wiegand, Root, Allen, Harrison, etc., and differ from them only in the number of parts, as the principle at- tempted to be embodied in the design of sectional or patent boilers appears to be the same in all, although attempts have been frequently made to show that their design was based on some new principle in the generation of steam, which, on examination, would be found to be only a vagary of the designer or in- ventor, an alteration from some former design, or at best only a slight improvement on some generator already in use. This appears to be the age of boil. ers; inventors are continually taxing their brains to produce new steam-boilers, but so far most of their productions have either proved a failure or a very poor investment. THE GALLOWAY BOILER. The shells of the Galloway boilers (English) are made of Bessemer steel, generally 3 of an inch thick. They have two furnaces to each boiler, composed of steel rings flanged and riveted together in such a manner that no seam or rivet comes in contact with the fire. The inside of the boiler is composed of an 288 USE AND ABUSE OF THE STEAM-BOILER. oval flue, in which are placed a number of conical water-tubes, having the smaller end at the bottom and the larger at the top. These tubes serve as braces for the large flue, and on account of their shape afford easy access for the steam in its escape from the heating-surface to the steam-room. Along the inside of the flue is a series of bafflers, which alter the direction of the heated gases from the furnaces to the chimney, and cause them to impinge on the water-tubes, thus increasing the heat- ' ing surface. These boilers are claimed to be very efficient, and capable of evaporating 102 pounds of water to one pound of coal, which, if true, has been fre- quently not only claimed, but accomplished in this country by boilers of more modest pretensions. The circumstances under which such wonderful evapora- tive capacity is developed, are rarely ever explained, and if investigated, it would probably be found that they were all very favorable to the boiler, possibly when the plates were new, clean, and free from in- crustation, the fuel of the best quality, the com- bustion as perfect as possible, and the management of the most intelligent and experienced character. The Galloway boiler owes its reputation in Eng- land to circumstances other than its efficiency, dura- bility, and economy. It is expensive to build, and also to repair, as it requires special appliances for either purpose. Such boilers are not at all adapted to this country, nor is it possible ever to introduce them here to any extent. Mf HE engineer’s duty, in the performance of the daily routine, involves the applica- tion of the laws of Nature in various ways. To build a fire intelligently ts a chemical experiment, involving a knowledge of the principles of combustion. The production of steam, and its wse as a motive power, depend, upon other laws equally impertant and in: . teresting’. . 25 T 289 290 USE AND ABUSE OF STRENGTH OF RIVETED SEAMS. The strength of a riveted seam depends very much upon the arrangement and proportion of the rivets; but, with the best design and construction, the seams are always weaker than the solid plate, as it is always necessary to cut away a part of the plate for the rivet holes, which weakens the holes in three ways :— lst, by lessening the amount of material to resist the strains; 2d, by weakening that left be- tween the holes; 3d, by disturbing the uniformity of the distribution of the strains. The first cause of weakness will appear obvious on the inspection of an ordinary boiler-seam, owing to the fact that forty- four per cent. of the original strength of the material had to be removed by the punch or drill to make way for the rivets. The second cause of the reduc- tion of strength is owing to the injury sustained by the plates during the process of drilling and punch- ing. The third cause of weakness is owing to the fact that if one or more holes are made in a plate of any material, and it is then subjected to a tensile strain, the strain, instead of being equally distributed through the section left between the holes, will be greatest in that part of the metal nearest it. The strength of boiler seams may be calculated by taking the area, in square inches, of the metal between the holes, and multiplying it by the ultumate _ strength of the metal, after the holes are punched. THE STEAM-BOILER, 291 Single-riveted seams being equal to 56 per cent. of the original strength, and double-riveted seams 70 per cent. COMPARATIVE STRENGTH OF SINGLE- AND DOUBLE-RIVETED SEAMS. On comparing the strength of plates with riv- eted joints, it will be necessary to examine the sec- tional areas, taken in a line through the rivet-holes, with the section of the plates themselves. It is 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 subject to such violent strains as boilers, the strongest method of riveting should be adopted. To ascertain this, a long series of experiments was undertaken by Mr. Fairbairn. There are two kinds of lap-joints, single- 292 USE AND ABUSE OF and double-riveted, as shown in Figs. 1 and 2 on opposite page. In the early days of steam-boiler construction, the former were almost universally employed, but the 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 off 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 linear foot, which, for ordinary diameters and average thickness of plate, are about six per foot or two inches from centre to centre; for larger diameters and heavier iron the distance between the centres is generally increased to, say two and one-eighth or two and one-fourth inches; but in such cases it is also neces- sary to increase the diameter of the rivet, for while five-eighth, or even half-inch, rivets will answer for small diameters and light plate, with large diameters and heavy plate experience has shown it to be neces- sary to use three-fourth to seven-eighth rivets. 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, more THE STEAM-BOILER., 293 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 it loses 44 per cent. of its strength; and, as a result, single-riveted seams are 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 Stevens Institute of Technology, Hoboken, N. J., that double- riveted seams are from 16 Fig. 1, | to 20 per cent. stronger than single-riveted seams — the SS > ose material and workmanship i moe being the same in both cases. 3 Fig, 2. 900 Q ao 070 0°9"9 ) HAND- AND MACHINE-RIVETING, Taking the strength of the NPARE SAtivecs ls. Lc crcovbocbkattedss 100 The strength of the double- riveted joint would then be 70 And the strength of the single- riveted would be.............. 56 The two methods most generally employed in uniting the riveted seams of steam-boilers are what are termed machine- and hand-riveting. In the former process, the rivet is upset with a single blow; while in the latter, the material is spread or distributed by 25 * 294 USE AND ABUSE OF a series of blows from hand-hammers. In the pro- cess of hand-riveting, the heads are rarely finished till the iron is cool enough to erystallize 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. The evil of the rivet not filling the hole well is sometimes aggravated in hand-work by the blows being dealt on the circumference of the point, in order to form a shoulder speedily to resist the ham- mering, instead of letting them fall dead on the point, which should tend to make the rivet first fill the hole before the shoulder is formed. The advan- tage of machine-riveting is that the machine upsets the rivet and closes up the hole better than hand- riveting, as the dead, heavy pressure is exerted through the whole mass of the rivet, and the effect is not concentrated upon the point, as it must be with a succession of light, sharp blows from a hammer. Then again, as the piston of the machine 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 half an inch too long or half an inch too short, thus accomplishing what no workman could possibly do. In machine-riveting, the heading is done on the “capping” system, thus gathering the metal to- gether instead of scattering it, as is the case with THE STEAM-BOILER. 295 the hand hammer. When it becomes necessary to take work apart, where the rivets have been driven, it is shown that the holes are thoroughly filled, and it is also found almost impossible to dislodge the rivets from the holes, while the holes were not more stretched than if the riveting had been done by hand. The shearing strain is less on machine- riveted joints than on those riveted by hand, on ac- count of 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, while the rivets and plates are left soft and free from any crystallization. The general conclusion drawn from practicai experience and observation is, that for good, sound boiler-work machine-riveting is the best. COUNTER-SUNK RIVETS, Counter-sunk rivets are generally tighter than any other form of rivet, because counter-sinking the hole is really facing it; and the counter-sunk rivet is, in point of fact, made on a faced joint. But counter-sinking the hole also weakens the plate, in- asmuch as it takes away a portion of the metal, and should only be resorted to where necessary, — such as around the fronts of furnaces, the flanges inside of combustion-chambers, and the bottom flanges of 296 USE AND ABUSE OF steam-chests. In these places it is by no means det- rimental ; but no part of the shell of a boiler, except those already mentioned, should be counter-sunk. RIVETS. The rivet is the means most generally, if not al- together, employed for uniting the seams of steam-boilers; aud it nay be taken as a rule, that j in any but the best class of work the rivet is stronger than the plate section between the holes. In old. boilers particu- larly, the plates at the joints are generally found to be much more brittle than the rivets, and the rivets, except at the heads, will escape corrosion, where the plate may suffer severely. It has been found by ex- periment that the strength of rivets of various sizes and descriptions in ordinary riveted work averaged 37,640 lbs. for single shear, and 34,000 Ibs. for double shear per square inch of sectional area. The shearing strength of iron rivets with thin steel plates has been found to be less than with plates of the same strength. This is probably due to the harder steel cutting into the iron of the rivet. The aver- age of eight experiments with steel plates and iron rivets gave 37,000 lbs. per square inch. oe THE STEAM-BOILER. 297 The strength of riveted seams may be calculated by Multiplying the area in square inches of one rivet by the number of rivets, and the product by the strength of the metal to resist shearing. TABLE SHOWING DIAMETER AND PITCH OF RIVETS FOR DIFFERENT THICKNESSES OF PLATE. SINGLE-RIVETED SEAMS. DouBLE-RIVETED SEAMS. Thickness} Diameter Pitch Thickness} Diameter of Plate. | of Rivet. of Plate. | of Rivet. + in.| 4 in.} 14 in: + in.} 4 in. > 6“ 5B & 13 6“ vs (q 4 “ ry 6“ re 74 1? “ce 3 73 4h bc | ie aL 3 6 lz «& re one “ns 66 1s “ 4 (14 3 “ A: ““c H “ 2 4 les 2 4 aint ‘“c 2 6c 24 “cc q's 6“ é 6c ts (74 a, (79 91 (79 5 (74 é 73 ri 6é u 6c at 6“ rh cc rs 6c 2-3 6 1 66 4 “c -. 6 1 “ in ‘“ : pes 21 “ rw “ yyy te oe 6c 1 (79 941 c¢ i 6c 1 (73 13 (73 Ki 66 gt (7 43 (a4 1} “ 74 1 4c 1 (9 <¢ (74 STRENGTH OF STAYED AND FLAT BOILER SURFACES. The sheets that form the sides of fire-boxes are necessarily exposed to a vast pressure, therefore some expedient has to be devised to prevent the metal at these parts from bulging out. Stay-bolts 298 USE AND ABUSE OF are generally placed at a distance of 43 inches from centre to centre, all over the surface of fire-boxes, and thus the expansion or bulging of one side is prevented by the stiffness or rigidity of the other. Now, in an arrangement of this kind, it becomes necessary to pay considerable attention to the tensile strength of the stay-bolts employed for the above. purpose, since the ultimate strength of this part of the boiler is now transferred to them, it being im- possible that the boiler-plates should give way unless the stay-bolts break in the first instance. Accordingly, all the experiments that have bcen made, by way of test, of the strength of stay-bolts, possess the greatest interest for the practical engi- neer. Mr. Fairbairn’s experiments are particularly valuable. He constructed two flat boxes, 22 inches square. The top and bottom plates of one were formed of 3-inch copper, and of the other 3-inch iron. There was a 23-inch water space to each, with 12-inch iron-stays screwed into the plates, and riveted on the ends. In the first box, the stays were placed five inches from centre to centre, and the two boxes tested by hydraulic pressure. In the copper box, the sides commenced to bulge at 450 pounds pressure to the square inch; and at 810 pounds pressure to the square inch the box burst, by drawing the head of one of the stays through the copper plate. In the second box, the stays were placed at 4-inch centres; the bulging THE STEAM-BOILER. 299 commenced at 515 pounds pressure to the square inch. The pressure was continually augmented up to 1600 pounds. The bulging between the rivets at that pressure was one-third of an inch; but still no part of the iron gave way. At 1625 pounds pressure the box burst, and in precisely the same way as in the first experiment—one of the stays drawing through the iron plate, and stripping the thread in the plate. These experiments prove a number of facts of great value and importance to the engineer. In the first place, they show that, with regard to iron stay-bolts, their tensile strength is at least equal to the grip of the plate. The grip of the copper bolt is evidently less. As each stay, in the first case, bore the pressure on an area of 5x5 == 25 square inches, and in the second on an area of 4X4=16 square inches, the total strains borne by each stay were, for the first, 815 x 25 = 20,375 pounds on each stay; and for the second, 1625 x 16 = 26,000 pounds on each stay. These strains were less, however, than the tensile strength of the stays, which would be about 28,000 pounds. The properly stayed surfaces are the strongest part of boilers, when kept in good repair. BOILER-STAYS. Advantage is usually taken of the self-supporting property of the cylinder and sphere, which enables 300 USE AND ABUSE OF them, in most cases, to be made sufficiently strong without the aid of stays, or other support. But the absence of this self-sustaining property in flat sur- faces necessitates their being strengthened by stays, or other means. Even where a flat or slightly dished surface possesses sufficient strength to resist the actual pressure to which it is subjected, it is yet necessary to apply stays to provide against undue deflection or distortion, which is liable to take place to an inconvenient degree, or to result in grooving long before the strength of the plates or their attach- ments is seriously taxed. . _ Boiler-stays, in any case, are but substitutes for real strength of construction. They would be of no service applied to a sphere subject to internal press- ure; and the power of resistance would be exactly that of the metal to sustain the strain exerted upon all its parts alike. The manner in which stays are frequently employed renders them a source of weak- ness rather than an element of strength. When the strain is direct, the power of resistance of the stay is equal to the weight it would sustain without tearing it asunder; but when the position of the stay is oblique to the point of resistance, any calculation of their theoretic strength or value is attended with certain difficulties. All boilers should be sufficiently stayed to insure safety, and the material of which they are made, their shape, strength, number, loca- tion, and mode of attachment to the boiler, should be THE STEAM-BOILER, 301 all duly and intelligently considered. Boiler-stays should never be subjected to a strain of more than one-eighth of their breaking strength. The strength of boiler-stays may be calculated by multiplying the area in inches, between the stays, by the pressure in pounds per square'inch. STAY-BOLTS. In the choice of material for stay-bolts for the furnaces of marine boilers and locomotives, and even stationary engines, there are other considerations besides that of strength alone. Iron would undoubt- edly be superior to any other material that could be employed for that purpose, if strength and its facili- ties for working were the only objects to be considered; but there are two evils that limit the usefulness of iron stay-bolts: first, they crystallize; second, they corrode. In either case they are likely to snap in half under any extraordinary pressure —that is, at the very moment when their services are most needed. Copper has neither of these faults. It has extreme tenacity up to a certain point of its working, and hot water does not corrode it in the least. Some engi- neers have tried the effect of placing iron stays in two or three of the upper rows, and copper in the lower rows, where the corrosive influence of the water is more powerful. But this is opposed to all 26 802 USE AND ABUSE OF practical experience, since the upper bolts are always found to break most frequently from the superior expansion of the inner plate; hence, the material that will endure the most bending should be em- ployed for them. Steel stay-bolts have been occasionally employed with good effect. When they have a spring temper, they seem to stand the effect of contraction and expansion better than any other material, since their small diameter and great elasticity permit them to conform to all moderate variations in the boiler caused by ordinary degrees of temperature. The safe working strength of copper, iron, and steel stay- bolts may be estimated at about one-fifth of the ulti- mate strength, which for steel is 80,000, iron 60,000, and copper 32,000; but if the screws are cut within the original diameter of the bolt, one-tenth of the working strength must be deducted. The following table shows the result of experi- ments on iron and copper stay-bolts screwed and riveted into iron and copper plates. rst, a 7-inch iron stay with enlarged head, screwed and riveted into a $-inch iron plate, failed by breaking through the shank with 25,000 pounds, the screw and plate remaining uninjured. Second, asimilar arrangement, but with a copper plate, failed with a load of 21,400 pounds, the head tearing off, and the copper threads stripping. Third, a -inch iron stay with enlarged end screwed into a é-inch copper plate, and not THE STEAM-BOILER. . 808 riveted, was drawn out of the plate by 16,200 pounds, the copper thread stripping. ourth, a ¢-inch copper stay with enlarged end, screwed and riveted into a ¢- inch copper plate, broke through the shank with 14,400 pounds, after stretching 3% of an inch. é Strength dis-|Strength dis- eee tribated over wributed over ee 25 ae area|16 oi area - wou give;/wou rive Pounds." Nba, per sq. in./|lbs. per a in, Ist. Iron into iron screwed and riveted...) 25,000 1,000 1,563 2d. Iron into copper screwed and riveted...) 21,400 856 1,338 3d. Iron into copper screwed only.......c.0 16,200 648 1,013 4th. Copper into copper screwed and riveted. | 14,400 576 900 CALKING. The object of calking is to bring together the seams of a boiler, after riveting, so that they may be perfectly steam- and water-tight. This is done by using a sharp tool ground toa slight angle. The edge of the plates being first chipped or planed to an angle of about 110°, the calking-tool is then applied to the lower edge of the chipped or planed angle, in order to drive or upset the edge, thus bringing the plates together and rendering the joint, to all appearances, perfectly steam-tight, and able to resist 304 USE AND ABUSE OF the internal pressure brought to bear upon this par- ticular point. The purely mechanical skill required to enable a person to join together pieces of metal, and thereby form a steam-tight and water-tight joint, was all that was heretofore considered necessary, as it had been almost universally thought that little more than this was needed, and that, provided the joint was tightly and well calked, or, in other words, “ made a good job of,” was all that was required. But, un- fortunately, this is but a small portion of the knowledge that should be possessed by persons who turn their attention to this subject, and experience has shown that persons engaged in this kind of em- ployment should possess a very dif- j ferent kind of . LM knowledge, other- wise the best ef- | forts of the manu- ante ule facturer of the Ordinary Method of Calking. material engine boiler-maker will be rendered useless. It is well known that the use of a hammer on wrought-iron will granulate, or harden, it to such an extent as to make it almost as hard as steel. Now, the angled tool before mentioned, through its action ' (in the process of calking) upon the lower edge of the chipped plate, causes a granulation of that plate; HELL THE STEAM-BOILER, 805 while the under one is much softer, in consequence of not being exposed to the action of the tool, conse- quently the skin, or outer surface of the softer mate- rial, is indented or cut. _ A boiler may be constructed by parties of high repute, be made of the best material, and, to all ap- pearance, be capable of standing any test that may be applied to prove its safety, and yet its durability may be very limited, or it may collapse or explode soon after being put in use, for the simple reason that a cause existed from the very first which could not be seen, and which no test could point out, and that cause was the grooving or indentation made by the calking, which became larger and larger through corrosion, expansion, and contraction, thus render- ing the plates unfit to resist the strain, which must eventually induce rupture or explosion, resulting in loss of life and destruction of property. This ten- dency to weaken the plates of steam-boilers, by the present mode of calking, may be illustrated by very familiar examples. | When a blacksmith desires to break his bar of iron to a given length, he first cuts around the bar, weakening it. The breaking is then easily accom- plished — frequently with one blow. A glazier sim- ilarly uses his diamond. Now, if a bar of iron, which has not been cut, be taken and submitted to blows, in a majority of cases it will bend to a right angle or more without showing any fracture. The explana- Pas Wen 306 USE AND ABUSE OF tion of this is, that by cutting a channel through the outer layer of fibre, the strain is confined to the point where the channel is cut. The fibre on either side, to the depth of the channel, is not acted upon at all, and exerts no influence as a protection to the under- lying layers of fibre. Hence, when the blow is re- ceived, the effect is confined to the channel, and the fibre, having little or no opportunity to protect itself, breaks short off. These illustrations are perfectly analogous to that of the cutting or indentation made by the old-fashioned calking-tool. On examination, steam-boilers are frequently found to be fractured along the edge of the outer lap of the sheet, both transversely and longitudinally, in consequence of a channel being entirely cut through the skin of the iron by the calking-tool, thus render- ing the plate weak at the point of the greatest strain. The force to act is ever present; the iron is already strained, as, by bending a sheet of iron to make a required circle, the fibres of the iron composing the outer circumference must, of necessity, be stretched ; and, by imperfect bending, will be stretched laterally as well as longitudinally, while the fibres of the iron composing the inner circumference are upset, and, if badly welded in the act of manufacture, pucker, thereby exposing the inside particles of the iron to the corrosive action of the acids in the water, pro- ducing honey-combing. Thus everything is ready for the cutting or grooving to be made — both the THE STEAM-BOILER, 807 strain on the outer, and the puckering on the inner, circumference. It then becomes only a mere ques- tion of time as to the result. Very few, except those familiar with the laws of steam, have any idea of the immense pressure exerted on the shells of steam-boilers under ress- ure; and when we consider that this immense press- ure is brought to bear along the lap of the joints — the points deviating farthest from the true cylin- drical form — the importance of having the iron not only of good quality, but free from the defects in- duced by inferior calking, must at once be admitted. Immense sums of money have been expended in experiments, with the object of ascertaining, if pos- sible, the cause of boiler explosions, which, if con- ducted by competent persons, might have proved, in many instances, to be the result of a mischievous system of calking. The cut on page 308 represents an improved method of calking, which is acknowledged by com- petent parties to be one of the most important improvements ever made in the construction of steam-boilers. It is the invention of James W. Con- nery, foreman of the Boiler Department at the Baldwin Locomotive Works, Philadelphia, and is known as Connery’s Concave Calking. By this method, the dangers to life and property induced by the old system of calking are entirely obviated, as even the uninitiated cannot dent or gall the plates 308 USE AND ABUSE OF with Connery’s Patent Calking; the importance of which will be’ appreciated by all steam-users, more especially when it is known that it is impossible, for Connery’s Concave Calking, even the most skilful’ boiler-maker, to calk a boiler with the old-fashioned calking-tools without perma- nent injury to the plates. TESTING-MACHINES. There is at present in this country a great need of cheap, simple, and reliable machinery for the purpose of testing the tensile strength of metals, particularly boiler-plate ; as it is of great importance to steam-users and the public to know exactly what strain iron of a certain kind or quality will bear without permanent set or fracture. When a boiler explodes, it is of great service to be able to test the tensile strain of the metal torn asunder, that some idea of the force exerted may be estimated, and also THE STEAM-BOILER, 3809 to know whether iron that has been subjected to heavy strains for a number of years has become “fatigued” or weakened. There are few machines in this country adapted to this business, and these are very expensive. The expense attending their construction, and the com- paratively little use to which they are put, have, without doubt, stood in the way of their construc- tion. If manufacturers and users of iron and other metals fully appreciated their value, they would be more frequently met with. ‘The materials for machines should be tested; and a proper under- standing of the exact strength which this material will sustain would, no doubt, often lead to improve- ment in design and construction. In some cases, the whole machine would be lighter, while in others it would possess proportions better adapted to sus- tain the heavy strains to which it may be subjected. FEED-WATER HEATERS. Inattention to the temperature of feed-water for . boilers is entirely too common, as the saving in fuel that may be effected by thoroughly heating the feed- water — by means of the exhaust-steam in a properly constructed heater — would be immense, as may be seen from the following facts : A pound of feed-water entering a steam-boiler at a temperature of 50° Fah., and evaporating into 310 USE AND ABUSE OF steam of 60 pounds pressure, requires as much heat as would raise 1157 pounds of water 1 degree. A pound of feed-water raised from 50° Fah. to 220° Fah. requires 987 thermal units of heat, which, if absorbed from exhaust-steam passing through a heater, would be a*tsaving of 15 per cent. in fuel. Feed-water, at a temperature of 200° Fah., entering a boiler, as compared, in point of economy, with feed-water at 50°, would effect a saving of over 18 per cent. in fuel; and with a well-constructed heater there ought to be no trouble in raising the feed-water to a temperature of 212° Fah. If we take the normal temperature of the feed- water at 60°, the temperature of the heated water at 212°, and the boiler pressure at 20 pounds, the total heat imparted to the steam in one case is 1192.5° — 60° = 1132.5°, and in the other case 1192.5°— 212° —= 980.5°, the difference being 152°, or a saving of 133.5 =138.4 per cent. Supposing the feed-water to enter the boiler at a temperature of 32° Fah., each pound of water will require about 1200 units of heat to convert it into steam, so that the boiler will evap- orate between 62 and 74 pounds of water per pound of coal. The amount of heat required to convert a pound of water into steam varies with the pressure, as will be seen by the following table: THE STEAM-BOILER. 811 ACS SHOWING THE UNITS OF HEAT REQUIRED TO CONVERT ONE POUND OF WATER, AT THE TEMPERATURE OF 32° FAH., INTO STEAM AT DIFFERENT PRESSURES. Pressure of Pressure of ee Gy tach Units of Heat. Oy Batak Units of Heat. by Gauge. by Gauge. 1 1,148. 110 1,187 10 1,155 120 1,189 20 1,161 130 1,190 30 1,165 140 1,192 40 1,169 150 1,193 50 1,173 160 1,195 60 1,176 170 1,196 70 1,178 180 1,198 80 1,181 190 1,199 90 1,183 200 1,200 100 1,185 | If the feed-water has any other temperature, the heat necessary to convert it into steam can easily be computed. Suppose, for instance, that its tempera- ture is 65°, and that it is to be converted into steam having a pressure of 80 pounds per square inch. The difference between 65 and 82 is 33; and sub- tracting this from 1181 (the number of units of heat required for feed-water having a temperature of 32°), the remainder, 1148, is the number of units for feed- water with the given temperature. Yet it must be understood that any design of heater that offers such resistance to the free escape of the exhaust-steam as to neutralize the gain that would otherwise be ob- Sip.u* USE AND ABUSE OF tained from its use, ought to be avoided, as the loss occasioned by back pressure on the exhaust, in many instances, counteracts the advantages derived from the heating of the feed-water. It is a common practice on steamships to heat . the feed-water to 135° or 140° before sending it into the boiler. Where the jet condenser is used, this extra heat is derived from the blow-water; but as this means of heating is not available with the surface condenser, it is generally derived from a water-jacket surrounding the smoke-stack, or a spiral pipe within the stack. But although any heat im- parted to the feed-water is a clear gain, yet the cost, complication, and danger of these arrangements gener- ally overbalance the benefits derived from their use. The feed-water should be sent into the boiler as hot as possible, as, if it be forced in at a low temper- ature, it will impinge on that portion of the boiler with which it comes in contact; and, as a result of the continual expansion and contraction induced by the varying temperature of the water, the boiler is liable to crack and become leaky. Where economy of fuel is no object, as is often the case at coal-mines, saw-mills, and wood-working establishments, a very inexpensive way of averting the dis- astrous effects of " ees pumping cold water Heater Pipe, . into boilers is to THE STEAM-BOILER. 313 introduce the feed-pipe into the back end of the boiler, carrying it forward about three-quarters the length of the boiler, and then returning it -to the back end, where the water is discharged into the boiler. - By this arrangement the water will have a temperature nearly equal to that of the water in the boiler when discharged from the pipe. Open feed-water heaters, though very efficient, are nevertheless objectionable, and should be avoided whenever any better arrangement is attainable. The grease from the cylinder mixes with the feed-water in such heaters, and on being carried into the boiler ‘combines with the carbonate of lime, sinks to the plates when the boilers are at rest, and is rarely ever afterwards moved by the circulation of the water, or even the most active boiling currents. By contact with the plates the water is kept from their surface, and the free transmission of the heat interfered with, which induces over-heating and burning of the plates. All feed-water heaters should be provided with the meaus of ascertaining the temperature of feed- water. This might be done by placing a hollow plug in a T on the feed-pipe, between the heater and the boiler, into which the bulb of a thermometer might be inserted at any time; and as the plug would be exposed to the action of the water in its passage from the heater to the boiler, its temperature might be easily ascertained. 27 314 USE AND ABUSE OF GRATE-BARS. Perfect combustion is the starting-point in the generation of steam; the conversion of coal and air into heat must be the first process, and the second is to apply that heat with full effect to the boiler. The oxygen of the air is the only supporter of combus- tion; and the rate of combustion produced, and the amount of heat generated in the furnace, depend on the quantity of air supplied; and the quantity of air admitted depends on the size of the opening through which it passes. Then, as a matter of course, the grate-bars offering the least obstruction to the air passing through them, and affording the largest area for the air combined, with an equal distribution of the same, must be the best adapted for the purposes of combustion. The failure of grate-bars is due mainly to three different causes — breaking, warping, and burning out; consequently, grate-bars, to be durable and efficient, should have a narrow surface exposed to the fire, the spaces for admitting the air being numer- ous and well distributed. The metal constituting the bar should be distributed in the best possible manner, to relieve the grate from all undue strain arising from unequal expansion and contraction ; there should also be considerable depth, in order that the lower edges may keep cool, and prevent the pos- sibility of warping or twisting. Grate-bars of good THE STEAM-BOILER. 315 design and proportions are frequently ruined by being exposed to a white heat, whenever a fresh fire is started, whereas, by distributing a thin layer of fresh coal over their surface before the shavings and wood are applied, they may be preserved intact for years. The grate-bar has not heretofore received the consideration from engineers and steam-users which its importance, in an economical point of view, so eminently deserves. CHIMNEYS. The object of a chimney is to convey away the smoke, and to produce a draught — that is, a current of fresh, dry air through the coals on the grate; this draught is produced hy the difference in the specific gravity of the air inside and outside of the chimney. If the quality of the gases inside and ' outside were always the same, formule could be established for the size of chimneys with a consid- erable degree of accuracy. The gases inside of a chimney are generally composed of atmospheric air, free nitrogen, carbonic acid, carbonic oxide, steam, free hydrogen, free carbon, sulphurous acid, and other elements. If the relative amount of these gases, and their temperature, were always the same, there would not be much difficulty in determining the proportions; but as these conditions are contin- ually changing, as well by the gradual consumption 316 USE AND ARUSE OF of the coai.on the grate as by the management of the party in charge, it is impossible to arrive at any exact or definite conclu- sion. The air outside the chimney is also continually undergoing changes, pro- duced by moisture, temper- ature, density, ete. For stationary and ma- rine boilers the chimneys are generally of a uniform height, arising from the nature of the structures with which they are con- nected, and hence the ap- proximate amount of com- bustion on a square foot of grate-surface, and the resulting evaporation of water per hour, are pretty well known from practical observations. For marine boilers, the general rule is to allow 14 square inches area of chimney for each nominal horse-power. For stationary boilers, the area of the chimney should be one-fifth greater than the combined area of all the flues or tubes. In boilers THE STEAM--BOILER. 317 provided with any other means of draught, such as a steam-jet or a fan-blower, the dimensions of the chimney are not so important as it is in cases where the draught is produced solely by the chimney. Rule for finding the Required Area of Chimney for any Boiler. — Multiply the nominal horse-power of ° the boiler by 112, and divide the product by the square root of the height of the chimney in feet. The quotient will be the required area in square inches. TABLE SHOWING THE PROPER DIAMETER AND HEIGHT OF CHIMNEY FOR ANY KIND OF FUEL. Nominal Horse- | Height ee Tiahia Diametarat op. | power of Boiler. in Feet. 10 60 1 foot 2 inches. | 12 75 j Ree 16 90 Direc, deen 20 99 Dee RN al 30 105 Lee aes 50 120 2feet2 “ 70 120 Pe Yi Sion 3s; 90 120 SOP eT esse 120 135 Oe a ae 160 150 IER eis | 200 | 165 oo Bake aR AS 250 180 Ln ee SOA 318 USE AND ABUSE OF TABLE SHOWING HEIGHTS OF CHIMNEYS FOR PRODUCING CERTAIN RATES OF COMBUSTION PER SQUARE FOOT OF AREA OF SECTION OF THE CHIMNEY. Pounds of Coal Burned Pounds of Coal Burned FG Heights in Feet, | Pet Hour per Square Root. of Grate. ao nate a? Chimn hi as of Grate to Section of ue Chimney being 8 to 1. 60 7.0 68 8.5 76 9.5 84 10.5 93 11.6 99 12.4 105 13.1 na 13.8 116 14.5 121 15.1 126 15.8 131 16.4 135 16.9 139 17.4 144 18.0 148 18.5 152 19.0 156 19.5 160 20.0 Though the above Table was arranged from data collected from what were considered reliable experi- ments, yet it may be said to be only approximately correct, as the conditions existing in different chim- neys and furnaces vary so much that no theoretical formuls will give results which can be relied upon as strictly correct. According to the experiments THE STEAM-BOILER. 319 of Mr. Isherwood, the best proportion for the draught area is } of the area of the grate. Many constructors, however, make it greater, amounting in some cases to 4 and }.. Others make it less, 4 being not uncommon. But experience has shown 1 to be the most practical proportion, and the one capable of producing the most satisfactory results. SMOKE. Ever since the days of Watt, the consumption of smoke has attracted the attention of scientists, in- ventors, and engineers, but, hitherto, without any very practical results, as the methods that offered the most plausible solution of the problem involved in the burning of smoke have invariably failed to pro- duce such results as would warrant their adoption and general use. A uniform supply of fuel to the furnace, and the introduction of air above the fire, were advocated as furnishing a remedy for the loss occasioned by smoke; but the former was, in most cases, found impracticable and inconvenient on ac- count of the varying circumstances involved in the management of furnaces; whilst the latter was fre- quently productive of more waste than that oc- casioned by smoke, in consequence of the current of cool air above the fire being constant, and the quan- tity of fuel on the grate, and the temperature of the furnace, varying very much. 320 USE AND ABUSE OF | From numerous smoke-stacks throughout the land can great volumes of smoke, as black as mid- night, be seen, at almost all times, rolling upward, carrying with them, to all appearance, the most valuable portions of the fuel. But it must be un- derstood that all that comes out of the chimney is not smoke by any means. Bituminous coal contains from five to six per cent. of hydrogen, which unites .with the oxygen necessary to combustion, and con- stitutes water. A ton of bituminous coal will make nearly one-third of a ton of water in the form of steam. That this steam is black, does not neces- sarily indicate the presence of much carbon, as a grain of soot, if distributed evenly in fine particles through a cubic foot of steam, would color it blacker than the ace of spades. Now it requires no argu- ment to show that this steam cannot be burned. It may be condensed by being made to pass through tubes kept at a low temperature, though a draught could only be maintained artificially under these conditions. Were it not for this mass of steam, the carbon | would soon fall as a cloud of black dust; but, being intimately and atomically mixed with the large volume of steam from the furnace, it is carried along by the atmosphere, only differing in color, like the cloud of steam we see issuing from the chimney of a locomotive when in action. With furnaces properly constructed, in which a thorough mixture of the THE STEAM-BOILER. 321 heated gases with air may be effected, as in the Bunsen burner, smoke might be partially consumed ; but the conditions under which this successful mix- ture of the air and gases may be effected are rarely ever found in the furnace of a steam-boiler, as the temperature is continually varying, while the quan- tity of air that passes into the furnace is constant. The volume of smoke may be diminished in ordinary furnaces by supplying the fuel in small quantities to one side of the furnace at a time, or by placing the fuel inside of the furnace door, then, when the smoke is consumed, move the fuel back and replace it with a fresh supply. This necessitates the con- tinual opeping and closing of the furnace door, which admits the cold air in such quantities as to lower the temperature in the furnace and defeat the object intended to be accomplished. As an object of comfort and convenience, the successful consump- tion of smoke is very much to be desired, but when once formed, smoke cannot be burned by any known process or device. CONTRIVANCES FOR INCREASING DRAUGHT AND ECONOMIZING FUEL IN BOILER FUR- NACKES. Where space is of no object, a large boiler, large grate, and high stack afford the best advantages for the combustion of the fuel employed for the gene- ration of steam; but whenever, on the contrary, Vv 322 USE AND ABUSE OF space and weight have to be economized, as in the case of locomotive and marine boilers, some means of increasing the draught and intensifying combus- tion becomes indispensable. For years, the question whether this object can be effected by means of water or steam has agitated the practical and scientific men of the country, many engineers and others uffirming that water does increase the heat of a fire, while almost all men of thorough scientific training hold that such an idea contradicts well known and recognized laws. The idea of a jet or jets of steam above or below the grate is very old, and descriptions of such ap- pliances are to be found in various publications on the burning of smoke; but the statements on this subject are very contradictory, and the benefits to be derived from the use of the steam-jet are as unde- cided at the! present day as in the days of Watt. The principal benefit claimed for the steam-jet is, that for every ton of oxygen required for the combustion of the fuel, four tons of useless nitrogen have to be heated from the ordinary temperature of the air to - that at which the gases escape into the chimney; whereas, by the use of the steam-jet, we increase the quantity of oxygen, and are enabled tintensify the combustion by diminishing the quantity of air ad- mitted, thus utilizing the heat that would otherwise be lost in raising the temperature of the useless nitro- gen to that of the escaping gases; or, in other words, THE STEAM-BOILER. S20 we will suppose that the incandescent coal derives a portion of the oxygen required for its combustion from the water, it is obvious that the amount of air that is required will be lessened in due proportion. A great number of experiments, both in this coun- try and Europe, have shown that there is nothing, in an economical point of view, to be gained by the use of either steam, or water, either in the increase of the draught of ordinary furnaces or in intensifying com- bustion,as,while the draught may besensibly increased, the consumption of fuel is not materially lessened, proof of which may be found in the fact that wherever such means are tried, they are sodn allowed to fall into disuse, if not entirely abandoned. For factory purposes, or where it becomes necessary to Consume a large quantity of fuel on a small area of grate, the fan-blower is undoubtedly the most practical, efficient, and convenient, as it not only intensifies the com-. bustion, but greatly increases the quantity of avail- able heat. The expense incurred in its employment is confined simply to the cost of the fan itself. 824 USE AND ABUSE OF TABLE SHOWING THE ACTUAL EXTENSION OF WROUGHT-IRON AT VARIOUS TEMPERATURES, Deg. of Fah. Length. Cr po aduo ating s i: 25 a lige eae 1.0011356 MOS neseedas 1.0025757 ) Surface becomes straw colored, deep Pat nahads tee 1.0043253 yellow, crimson, violet, purple, "1 Ade 1.0063894 deep blue, bright blue. OSE iesases yitped Surface becomes dull, and then te ES ae 1.0114811 bright red. : dee Se eonerce se Bright red, yellow, welding heat, ye ile 10512815) White heat. DOLD ccesecses Cohesion destroyed. Fusion perfect. Linear Expansion of Wrought-iron.—The linear expansion which a bar of wrought-iron undergoes, according to Daniell’s pyrometer, when heated from the freezing- to the boiling-point, or from 32° to 212° Fah., is about gd, of its length; at higher tempera- tures, the elongation becomes more rapid. Thus, it will be seen how sensible a change takes place when ‘iron undergoes a variation of temperature. A bar of iron, 10 feet long, subject to an ordinary change of temperature of from 32° to 180° Fah., will elon- gate more than } of an inch, or sufficient to cause fracture in stone work, strip the thread of a screw, or endanger a bridge, floor, roof, or truss, or even push out a wall if brought in contact with it. THE STEAM-BOILER. 825 The expansion of volume and surface of wrought- iron is calculated by taking the linear expansion as unity ; then, following the geometrical law, the super- ficial expansion is twice the linear, and the cubical expansion is three times the linear. Wrought-iron will bear on a square inch, without permanent alteration, 17,800 pounds, and an exten- sion in length of 54/55. Cohesive force is diminished z000 by an increase of 1 degree of heat. Compared with cast-iron, its strength is 1.12 times, its extensibility 0.86 times, and its stiffness 1.3 times. : Cast-iron expands 73555 of its length for 1 de- gree of heat; the greatest change in the shade, in this climate, is ;;4, of its length; exposed to the sun’s rays, za\p0- Cast-iron shrinks, in cooling, from ,'; to gy of its length. Cast-iron is crushed by a force of 93,000 pounds — upon a square inch, and will bear, without permanent alteration, 15,300 pounds upon a square inch. To find the surface dilatation of any particular article, double its linear dilatation; and to find the dilatation in volume, tripleit. To find the elongation in linear inches, per linear foot, of any particular article, multiply its respective linear dilatation, as given in the table, by 12. 28 326 USE AND ABUSE OF TAB: SHOWING THE LINEAR DILATATION OF SOLIDS BY HEAT, Length which a Bar Heated to 212° has greater than when at the Temperature of 32°. SIGSS, Caster. st caunrenies ries heepe eevee temas 0018671 COOPPOR sean s de> senkate’ dareucpeeimeaem tee ayne weaned 0017674 (ROLE Pool iees hie Babe tts sivemin en Ue neaetone lanign de 0014880 Proms Gasty ocipeeaces oie eanneirecuaras elastin 0011111 LYOR, WLOURtedisedarened soso suerteand tegen th trores 0012575 SUL Er sa ecee svecne a teoen 4ariae nou nph ee secvameay tre sst 0020205 Steel egecssescvec see yeesesawabeusvevesnve chedeldcaury PE IRIE aes os a DEDUCED 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 temperature of 550° above the freezing-point, at which point its tenacity began to diminish. At 32° to 80° tenacity is 56,000 Ibs., or + below its maximum. “ ifs “ “ if3 570° «© 66.000 « 720° «55 000 1050° « © 39.000 * 1240° «99.000 1317° « ) # 9000 « the maximum. the same nearly as at 30°. nearly 4 the maximum, nearly + the maximum. nearly } the maximum. © Jt 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 water, the iron would _ soon become reduced to less than one-half its strength. oN yf THE STEAM-BOILER, 327 TABLE SHOWING THE RESULTS OF EXPERIMENTS MADE ON DIF- FERENT BRANDS OF BOILER IRON AT THE STEVENS IN- STITUTE OF TECHNOLOGY, HOBOKEN, N. J. Thirty-three experiments were made upon the iron taken from the exploded steam-boiler of the ferry-boat “ Westfield.” The following were the re- sults: Lbs. per. sq. in. Average breaking weight.........cscccscssessseens 41,653 16 experiments made upon high grades of American boiler-plate. Average breaking Weight, .....e+..0sevensesesesoeess 54,123 15 experiments made upon high grades of American flange-iron. Average breaking weight......cscses sesccsescsceess 42,144 6 experiments made upon English Bessemer steel. Average breaking weight.........sssssecsesersterees 82,621 5 experiments made upon English Lowmoor boiler- plate. 2 Average breaking weight..}.........sssseeceesee vee 58,984 6 experiments made upon samples of tank iron taken from different manufacturers. Average breaking weight No, 1......s.ssessseeees 43,831 é “ «“ NO¢ Diccesessu eng receerees bevO De «“ a6 y Noi Sea eee 41,249 2 experiments made on iron taken from the ex- ploded steam-boiler of the Red Jacket. Average breaking weight..... ...csssessersersseeees 49,000 It will be noticed that the above experiments re- veal a great variation in the strength of boiler-plate of different grades. ———- - USE AND ABUSE OF 828 o gler silo oc|s, 362, ote r]ot olf Bp I i ¢ 3 t é t $v seyouy ur ssouyoryy, “SSHNMOIHL WHd SV LOOH TVIOIWHHdOS YHd SAULVId NOUWI-LSVO AO LHOSIDM ZOE | SES |F60T FEST) LAT |T6STTSPT/ ELST /FLZT| STL | GOT |TOOT| £26 | TPS |TLL|F0L| S4'T ur 4A, SI | GI | FIL! It | 01 | Zor | F0T| or | é6 | #6 | t6 | 6 | #8 | $8 | ¥8) 8 | ‘sur ur vig ¥9 | 8 Felt z4lFa4|é29| Fee] Foo! 92 | ez | 02 | AT EPTFat |For] $8 | 2 | Fo | S| Fe | saT ot aM $L\42\%2| 4149/79/49] 9 |t¢/¥¢)t¢| ¢ |r| ae €¢|i¢|te} ¢ [sul ur vig "UHLANVIG NI SHHONI €T OL ¢ WOUA STIVE NOUI-LSVO AO LHDIAM AHL ONIMOHS MW ‘Iad Vib 829 THE STEAM-BOILER. ¥e6 | $28 | t08 | ez | $99 | ¢9 | 09 | ¥9¢\Fe¢/ Foc] gp | Fer | Fo | -8q7T Ut TysIOM © G | iy | a | ey | te | ey | ty | ip | & | seqouy ur sojourerqg 83 | 92 | #2 | GS | OZ | FST | EOL] ST | FSL | SqrT Ut ysIOM t€ | is | & | 23 | #0 | $a | fo | 8% | to | seuouy uy soyoureiq 9 | ¢|4|#el3e} 2) 8t) til & foesqy ur seq i | | a0 | er | §t | tt] et | dr] tt] t | | E | OS | SE | soqouy ur soyomerg ‘aja ‘buufoyy fo qybiayy ayy buynpnanp sog ‘ONOT LOO | ‘AHLAWVIC SHHONI 9 OL HONI NV $ WOUA NOUI-CNQOU AO LHDIGM AHL SNIMOHS a'Iad Vio 28 * eee” USE AND ABUSE OF 330 r-loo a) t¥9| 19 |€1G| FE ee ee ht = roo = fe | te | $¢ e|00 ine) FT Sqr] UT TAA segrenbg 8 “bs "yy 10d “eq T UM. e¢ Ze] 9z |$ez\teu] Zz | 6L | LT EST FST| Zt oT! 6 | FL] 79 |t Sol ¢ | #2 | £%| 8¢/ $e | 8a| 4a | a) & Er) et] et 41 ere ONOT LOOM | ‘AUVODS ‘SNI 9 OL ‘NI NV } WOU ‘NOUI-UVA auv ads HO LHDIAM FHL OSNIMOHS AIaAVG ez |40z| oz | ¥z1| et | $1 a Aca 8 A aL ot su] UL UT, ‘YOIHL HONI Nv OL Hi2! Woud GNV TUVADS LOOA T SHALVId-UNTIOM AO LHDIAM AHL ONIAOHS aA TAV GE THE STEAM-BOILER, . 3831 TABLE SHOWING THE WEIGHT OF CAST-IRON PIPES, 1 FOOT IN LENGTH, FROM + INCH TO 1} INCHES THICK AND FROM 3 INCHES TO 24 INCHES DIAMETER, 1393/1564 145 |1623 154 |1734 165}|185} 1763198 1874/2114 198}|2233 | 209 |235} 2221/2947 2331|259 24341273} 2448/9851 2654|298} 277413104 RS SEE - g THICKNESS IN INCHES. as 8 ad Latent, cere en el Pay | leo: Lee ope Lbs. | Lbs. | Lbs. | Lbs. | Lbs. | Lbs. | Lbs. | Lbs. | Lbs. 3 PL oe LUE faked |) Gal Elvonanss|esce ses |ooduess| aameen 3h PTA LORY Ole (BI dl ce cist sdasodeh sascter ene 4 BO LOR 22 bh 28a Nd Bey 4 cased te Lalvleen= baie dando cpenien BeeaW PIS ViF4h | She | BOR na, deeds s.stesaseentagnenen 5 Ie | 19F 1°27. |) 8441; 4241 BOS] 759 beccicec licens Be) 15 | 214 |} 293) 374.) 46°|~ B49] 6391... 0 ee Og a 234 | 82 | 40%] 493} 59 | 683) 783] 883 SAL San 5 251 | 344 | 43% | 534] 634] 734] 844] 95 Bee ale cased 271 | 36% | 462 | 563! 673) 784) 89211014 i, aap oreieee 29 |.39 | 50 60%! 72 | 833) 95411073 a eae 30% | 412 | 53 645| 764] 883) 100%|1133 ut Renee 33 | 444 | 564); 682] 80%] 933) 1063/120 ee hae 344 | 464] 59 | 713] 84%] 984] 1113/1253 1 1174|132 $a2 USE AND ABUSE OF a A Be SHOWING THE TENSILE STRENGTH OF VARIOUS QUALITIES OF AMERICAN CAST-IRON. Breaking weight of a square inch bar. Common pig-iron, Good common caeulaee, Cast-iron, «cc 6c 73 (f9 Gun-heads, specimen from, . “cc ‘c 6é Greenwood cast-iron, ; i ; ; § (after third melting,) . Mean of American cast-iron, ; Gun-metal, mean, ; ; i English Cast-Iron. Lowmoor, q ; : , é Clyde, No. 1, Clyde, No. 3, Calder, No. 1, Stirling, mean, Mean of English, . Stirling, toughened iron, Carron No. 2, cold-blast, ‘ “« 2, hot-blast, i “3, cold-blast, ig “ 3, hot-blast, Davon, No. 3, hot-blast, Buffery, No. 1, cold-blast, 3 “ 1, hot-blast, Cold-Talon (North Wales), No. 2, cold-blast, “ 2) hot-blast, . 15,000 . 20,000 , 20,834 . 19,200 . 27,700 . 24,000 . 39,500 . 21,300 . 45,970 . 31,829 . 87,282 . 14,076 . 16,125 . 23,468 . 18,735 . 25,764 . 19,484 . 28,000 . 16,683 . 13,505 . 18,200 . 17,755 . 21,907 . 17,466 . 18,487 . 18,855 . 16,676 THE STEAM-BOILER. dau A BL, SHOWING THE TENSILE STRENGTH OF VARIOUS QUALITIES OF AMERICAN WROUGHT-IRON. Breaking weight of a square inch bar. From Salisbury, Conn., . : ; : . 66,000 “Pittsfield, Mass., : : . 57,000 ‘“< Bellefonte, Pa., j : i : . 58,000 ‘< Maramec, Mo., : : ; : . 48,000 es Ny Ns ‘ ; ? é . 58,000 “ Centre County, Pa.,. ; : : . 58,400 “« Lancaster County, Pa. . ¢ ; . 98,061 “Carp River, Lake Superior, . ; . 89,582 “ ~ Mountain, Mo., charcoal bloom, : . 90,000 American hammered, 3 , ’ ; . 53,900 Chain-iron, A ; . ; i ; . 48,000 Rivets, : ; ‘ , : : : . 58,300 Bolts, . : P ‘ : ; ‘ , . 52,250 Boiler-plates, . ; : 4 ‘ . . 80,000 Average boiler-plates, : : ‘ : . 55,000* “« joints, double-riveted, . ’ : . 85,000 3 SeMec ATONE Ths. : ; : . 28,600 Chrome steel, highest strength, . : : . 198,910 . lowest uf ; : : . 168,760 * average “ ‘ § 4 . 180,000 Homogeneous metal, ae : : . 105,782 + «2d quality, ‘ , . 81,662 Bessemer steel, . : : ; : ; . 148,324 2 PR RO OR Se Ae NRT EHD RON gS Wp . . ° , “ : : h . 157,881 334 USE AND ABUSE OF TABLE SHOWING THE TENSILE STRENGTH OF VARIOUS QUALITIES - OF ENGLISH WROUGHT-IRON. Breaking weight of a square inch bar. English bar-iron, ‘ : : ; ; . 56,000 Iron, mean of English, ; , ; , . 938,900 ‘rivets, ; : ; ‘ ‘ F . 65,000 Lowmoor iron, . ; : : “ : . 56,100 Lowmoor iron plates, . : ‘ ; : . 07,881 Bowling plates, . . ‘ é : : . 53,488 Glasgow best boiler, . ; : 5 : . 56,317 + ship plates, . . ‘ d : . 53,870 Yorkshire plates, hs : ; : ; . 07,724 Staffordshire plates, . . : . ‘ . 48,821 Derbyshire plates, ; ; ; : ; . 48,563 Bessemer wrought-iron, ‘ ; . : . 65,253 vi : * : : : A . 76,195 ‘ 66 66 : y ; . ; 82,110 Russian cS " ‘ : . : . 99,500 : i ef : ‘ : . ., 76,084 Swedish i e ; > " ‘ . 58,084 TO POLISH BRASS. Engineers will find the following receipt a very good one for polishing the brass work of their engines. Oxalic acid dissolved in rain- or cistern-water, in the proportion of half an ounce to a pint of water, if applied with a rag or piece of waste, will re- move the tarnish from brass and render it bright; the surface should then be rubbed with an oily rag THE STEAM-BOILER. 835 and dried, and afterwards burnished with chalk, whiting, or rotten-stone. This is probably one of the quickest known methods for cleaning brass. A mix- ture of muriatic acid and alum, dissolved in water, imparts a golden color to brass articles that are steeped in it for a few seconds. Owing to irregularities of surface, it often hap- pens that considerable difficulty is encountered in putting a good polish on articles of brass or copper. If, however, they be immersed in a bath composed of aqua-fortis, 1 part; spirits of salt, 6 parts; and water, 2 parts, for a few minutes, if small, or about half an hour, if large, they will become covered with a kind of black mud, which, on removal by rinsing, displays a beautiful lustrous under-surface. Should the lustre be deemed insufficient, the immersion may be repeated, care always being taken to rinse thoroughly. All articles cleaned in this manner should be dried in hot, dry sawdust. Another receipt for cleaning brass, nickel-plated ware, or German silver, is to dissolve one ounce of carbonate of ammonia in four ounces of water, after which it should be mixed with 16 ounces of Paris: white. To apply it, moisten a sponge with water, dip it in the powder, rub quickly and lightly over the surface of the metal, after which it may be rub- bed over with some of the dry powder on a soft cloth or piece of clean waste. 836 USE AND ABUSE OF CEMENT FOR MAKING STEAM-JOINTS. Take a quantity of pure red-lead, put it in an iron mortar, on a block or thick plate of iron. Put in a quantity of white-lead ground in oil; knead them together until you make a thick putty; then pound it; the more it is pounded, the softer it will become. Roll in red-lead and pound again; repeat the operation, adding red-lead, and pounding until the mass becomes a good stiff putty. In applying it to the flange or joint, it is well to put a thin grummet around the orifice of the pipe, to prevent the cement being forced inward to the pipe when the bolts are screwed up. When the flanges are not faced, make the above mass rather soft, and add cast-iron borings run through a fine sieve, when it will be found to resist either fire or water. Another Cement. — Powdered litharge, 2 parts; very fine sand, 2 parts; slacked quick-lime, 1 part. Mix all together. So use; mix the proper quantity with boiled linseed-oil, and apply quickly. It gets hard very soon. Another Cement.— White-lead ground in oil, 10 parts; black oxide of manganese, 3 parts; litharge, 1 part. Reduce to the proper consistency with boiled linseed-oil, and apply. Another Cement. — Red-lead ground in oil, 6 parts; white-lead, 3 parts; oxide of manganese, 2 parts; THE STEAM-BOILER. oot silicate of soda, 1 part; litharge, + part; all mixed and used as putty. Another Cement.— Take 10 pounds of ground litharge, 4 pounds of ground Paris white, + pound of yellow ochre, and 3 ounce of hemp; cut into lengths of 4 inch; mix all together with boiled lin- seed-oil, to the consistency of a stiff putty. This cement resists fire, and will set in water. Cement for Rust-Joints. — Cast-iron borings or turn- ings, 19 pounds; pulverized sal-ammoniac, 1 pound; flour of sulphur, 2 pound. Should be thoroughly mixed and passed through a tolerably fine sieve. Sufficient’ water should be added to wet the mixture through. It should be prepared some hours before being used. A small quantity of sludge from the trough of a grinding-stone will improve its quality. Rust-joints, composed of sal-ammoniac, iron bor- ings, flour of sulphur, and water, were formerly em- ployed for all the permanent joints around engines ; — but they are fast going out of use and being replaced by faced joints. Red-lead joints were also very generally used, but they are now obsolete, and justly so, not only for their dirty appearance, but also for the difficulty ex- perienced in starting them, as it required, in most cases, the use of sledges and chisels, which incurred the danger of breaking the flanges. Ail movable joints of the best description of land and marine engines are now faced on a lathe or 29 WwW 4 Soa USE AND ABUSE OF planer, and then rendered perfectly steam-, air-, and water-tight by filing and scraping, so that all that is necessary, when put together, is to oil their surfaces. For smooth surfaces that can be conveniently calked, sheet copper, annealed by heating it to a cherry red, and then plunging it in cold water, makes a permanent joint. Lead wire makes a very cheap, clean, and per- manent joint. Copper wire also makes a very good joint; but, when convenient, it is always best to plane or turn a groove in one of the surfaces to be brought in contact. For uniform surfaces, gauze wire-cloth, coated on either side with white- or red-lead paint, makes a very durable joint, particularly where it is exposed to high temperatures. For pumps of stand-pipes in the holds of vessels, canvas well saturated on both sides with white- or red-lead makes a very durable joint. Pasteboard painted on both sides with white- or red-lead paint is frequently used with good results. STEAM- AND FIRE-REGULATORS. The numerous devices which have been employed by engineers for maintaining a uniform pressure of steam in boilers, shows the importance of a con- trivance for this purpose. As a consequence, many steam- and fire-regulators have been introduced to ; i 2 ; : | THE STEAM-BOILER. 339 LLY “a mw _— LZ on (I le TT, | ~~ MS SSE YARN CRC. Y WR AUTOMATIC STEAM-DAMPER, 3840 USE AND ABUSE OF THE STEAM-BOILER, the public; but most of them, from complexity or want of good workmanship, have failed to give satis- faction, and in many instances have proved to be of more injury than advantage. _ The cut on page 839 shows an improved self-ad- justing steam- and fire-regulator, simple and durable in its construction, and not liable to derangement or loss of sensitiveness from time or use ; having perfect control of the damper, it will, when once set to any required pressure, maintain that pressure in the boiler so long as the required quantity of fuel is supplied. These machines are in successful operation throughout the country ; they maintain an even head of steam, with economy in the consumption of fuel, safety to the boilers, and general saving in wear and tear. The following advantages are secured by these Regulators: Uniformity of pressure in the boiler. Economy of fuel averaging ten per cent. Freedom from explosions induced by excessive pressure. For these appliances, or any information concerning them, address S. ROPER, 447 NortH Broap STREET, PHILA. INDEX. Adaptability of the steam-boil- er, 16. Adjuncts of the steam-boiler, 27. Allen boiler, the, 235. Arched boiler-heads, 51. Arrangement and diameter of tubes, 156. Babcock and Wilcox’s sectional steam-boiler, 174. Blisters, 266. Boiler, double-deck, 31. drop-flue, 32. explosions, experimental, 223. flue, 29. flues, 189. furnaces, contrivances for in- creasing draught and econ- omizing fuel in, 321. Harrison, 138. Boiler-heads, 50. arched, 51. flat, 51. Boiler iron when broken, charac- teristics of, 267. locomotive, 33. making, 264. materials, 264. materials, thickness of, 60. plates, practical limits to the thickness of, 271. Roger’s and Black, 129. 29 * Boiler seams, punched and drilled holes for, 281. stays, 299. the Allen, 235. the Galloway, 287. the Phleger, 159. the Root, 226. the Shapley, 154. tubes, 155. tubular, 30. vertical marine, 46. Boilers and boiler materials, definitions as applied to, 277. expansion and contraction of, 80. fire-box, 34. : length of, 60. marine, 41. patent, 287. size of, 37. tubulous, 35. Calking, 303. Care and management of steam- boilers, 237. Cement for making steam-joints, 336. for rust-joints, 337. Characteristics of boiler iron when broken, 267. | Chimneys, 315. 341 342 Clapp and Jones’ vertical circu- lating tubular boiler, 69. Cohesion, 277. Collapsing pressure of wrought- iron boiler flues 4% inch thick, 149. pressure of wrought-iron boil- er-flues 7’s inch thick, 150. pressure of wrought-iron boil- er-flues 3g inch thick, 151. pressure of wrought-iron boil- er-fiues is inch thick, 152. Comparative strength of single- and double-riveted seams, 291; Concussive ebullition, 218. Connections and attachments, steam-boiler, 165. Contrivances for increasing draught and economizing fuel in boiler furnaces, 321. Corrosion of marine boilers, 77. of steam-boilers, internal and external, 73. Counter-sunk rivets, 295. Crushing strength, 278. Curvilinear seams, 277. Cylinder boiler, plain, 28. Dampers, 258. Defects in the construction of steam-boilers, 230. Definitions as applied to boilers and boiler materials, 277. Design of steam-boilers, 25. Detrusive strength, 278. Diameter and arrangement of tubes, 156. and length of steam-boilers, ete., £9. Disadvantage inherent in sec- tional steam-boilers, 41. INDEX. Double-deck boiler, 31. Drop-flue boiler, 82. Durability of steam-boilers, 26. Ebullition, concussive, 213. Economy of steam-boilers, 26. Effect of punching on steel- plates, 275. ‘ Effects of different kinds of fuel on steam-boilers, 263. Elasticity, 278. limit of, 278. Evaporation in steam-boilers,61. Evaporative efficiency of steam- boilers, 63. efficiency of steam-boilers, methods of testing the, 70. efficiency of tubes. 158. Expansion and contraction of boilers, 80. Experimental sions, 223. Explanation of tables, 118. of tables of collapsing press- ures, 148. Exploded boiler of locomotive “Charles Willard,” 222. boiler of the ferry-boat ‘‘ West- field,” 208. Explosions, steam-boiler, 209. Explosive gases, 212. boiler explo- Fatigue of metals, 279. Feed-water heaters, 309. Fire-box boilers, 34. Flat boiler-heads, 50. Flue boiler, 29. Foaming in marine boilers, 191. in steam-boilers, 189. Forms of steam-boilers, 27. Fuel on. steam-boilers, effects of different kinds of, 263. INDEX. Galloway boiler, the, 287. Gases, explosive, 212. Gauge-cocks, 167. Glass water-gauge, 173. Grate-bar, 314. surface to heating surface, proportion of, 73. Hiand-and machine-riveting, 293. Harrison boiler, 138. Heaters, feed-water, 309. Heating surface, etc. ,table show- ing number of square feet of, 47. surface of steam-boilers, 92. Horse-power of steam-boilers, 92. Hydraulic test, 106. Improvements in steam-boilers, 194. Incrustation in steam-boilers, 194. Inspection, steam-boiler, 260. Integrity of steam-boilers,causes which affect the, 19. Internal and external corrosion of steam-boilers, 73. grooving in steam-boilers, 78. radius, 278. Iron pboiler-plate, strength of, 275. boilers, table of safe internal pressures for, 123. Lamination, 266. Latta steel coil boiler, 89. Length of boilers, 60. Lift of safety-valves, 183. Limit of elasticity, 278. Linear expansion of wrought- iron, 324. Location of steam-boilers, 135. 343 Locomotive boiler, 33. Longitudinal seams, 278. Marine boiler, vertical, 46. boilers, 41. boilers, corrosion of, 77. boilers, foaming tn, 191. tubular boiler, 42, Materials, boiler, 264. Metals, fatigue, 279. Methods of testing the evapora- tive efficiency of steam-boil- ers, 70. Moorhouse safety sectional boil- er, 98. Mud-drum, 56. Negtect of steam-boilers, 110. Over-heating, 216. Over=-pressure, 215. Patent boilers, 287. Petroleum, 206. Phleger boiler, 159. Pierce’s rotary tubular boiler, 133. Plain cylinder boiler, 28. Practical limits to the thickness of boiler-plates, 271. Prevention and removal of scale in steam-boilers, 197. Priming in steam-boilers, 192. Proportion of grate surface to heating surface, 73. Pulsation in steam-boilers, 131. Punched and drilled holes for boiler-seams, 281. Punching on steel-plates, effect of, 275. Radius, internal, 278. 344 INDEX. Receipt for preventing formation | Fle for finding the safe external of scale, 204. Red-lead joints, 328. Regulator, steam- and fire, 340. Repairing steam-boilers, 107. Resilience, 279. Riveted seams, strength of, 290. Rivets, 296. counter-sunk, 295, Roger’s and Black boiler, 129. Koot boiler, the, 226. pressure on boiler-flues, 142. for finding the safe working- pressure of steel and iron boilers, 115. for finding the weight neces- sary to put on a safety-valve lever, when the area of valve, pressure, etc., are known, 184. for finding the heating sur- Kotary tubular boiler, Pierce's, 133. Kule for cylinder boilers, 88, 262. for finding centre of gravity of taper levers for safety- valves, 186. for finding the aggregate strain caused by the press- ure of steam on the shells of boilers, 118. for finding the collapsing pressure of boiler-flues, 148. for finding the heating surface of vertical tubular boilers, 88. for finding the pressure at ‘ which a safety-valve is weighted when length of lever, weight of ball, etc., are known, 186. for finding the pressure per square inch of sectional area on the crown-sheets of © steam-boilers, 117. for finding the pressure per square inch when the area of valve, weight of ball, etc., are known, 185. for finding the required area of chimney for any boiler, 317. face of steam-boilers, 87. for finding the quantity of water which boilers and other cylindrical vessels are capable of containing, 262. for flue-boilers, 88, 262. for locomotive or fire-box boilers, 87. for tubular boilers, 88. to find the required height of a column of water to supply a steam-boiler against any given pressure of steam, 263. to find the requisite quantity of water for a steam-boiler, 263. Rust-joints, 337. cement for, 337. Safe load, or safe working-press- ure, 279. Safety of steam-boilers, 26. sectional boiler, Moorhouse, 98. Safety-valves, 176. lift of, 183. Safe working-pressure of steam- boilers, 115. working-pressure of steel and iron boilers, rule for finding the, 115. INDEX. 345 Safe working-pressure or safe | Steam-boilers, durability of, 26. load, 279. Seams, comparative strength of single- and double-riveted, 291. curvilinear, 277. longitudinal, 278. Sectional boiler, Wiegand, 111. steam-boilers, 38. steam-boilers, inherent in, 41. Selection of steam-boilers, 129. Setting steam-boilers, 100, Shapley boiler, 154. Silsby’s vertical tubular boiler, 80. Size of boilers, 37. Smoke, 319. Sound test, 106. Spheroidal theory, 213. Stay-bolts, 301. Stayed and flat boiler surfaces, strength of, 297. Steam and fire regulator, 340. Steam-boiler, adjuncts of the. 16. Babeock and Wilcox’s sec- tional, 174. connections and attachments, 165. explosions, 209, explosions, vagaries of experts in regard to, 227, inspection, 260. Steam-boilers, 17. adaptability of, 27. care and management of, 237. causes which affect the integ- rity of, 19. defects in the construction of, 230, design of, 25. disadvantage econoniy of, 26, effects of different kinds of fuel on, 268. evaporative efficiency of, 70, 63. foaming in, 189. forms of, 27. heating surface of, 838. horse-power of, 92. improvements in, 2338. incrustation, 194. internal and external corro- sion of, 73. internal grooving in, 78. location of, 135. methods of testing the evapo- rative efficiency of, 70. neglect of, 110. prevention and removal of scale in, 197. priming in, 192. pulsation in, 131. repairing, 107. rules for finding the heating surface of, 87. safety of, 26. safe working-pressures of, 115. sectional, 38. selection of, 129. ® setting, 100. strength of, 26. testing, 103. water-space and steam-room in, 58. N Steam-damper, 339. domes, 53. gauges, 170. joints, cement for making, 336, room and water-space in boil- ers, 58. diameter and length of, 59. Steel, 272. 346 INDEX. Steel boilers, table of safe inter- nal pressures for, 119. Steel-plates, effect of punching on, 275. Strength, 278, crushing, 278. detrusive, 278, of iron boiler-plates, 275. of riveted seams, 290. of stayed and flat boiler sur- faces, 297. of steam-boilers, 26. tensile, 278, torsional, 278. transverse, 278, working, 279. Stress, 279, Table deduced from experiments on iron plates for steam- boilers, by the Franklin In- stitute, Philadelphia, 326. of comparison between ex- perimental results and theo- retical formule, 182. of safe internal pressures for iron boilers, 1238. of safe internal pressures for steel boilers, 119. of safe Working external pres- sures on flues 10 feet long, 144. of safe working external pres- sures on flues 20 feet long, 146. of squares of thickness of iron, and constant numbers to be used in finding the safe ex- ternal pressure for boiler- flues, 143. of superficial areas of exter- nal surfaces of tubes of various lengths, diameters’ in square feet, 160. Table of superficial areas of tubes of different lengths and diameters from 2% inches to 3 inches and from 8 feet to 20 feet, 165. showing diameter and pitch of rivets for different thick- nesses of plate, 297. showing heights of chimneys for producing certain rates of combustion per square foot of area of section of the chimney, 318. showing the actual extension of wrought-iron at various temperatures, 324, showing the linear dilatations of solids by heat, 326. showing the number ofsquare feet of heating-surface, 47. showing the proper diameter and height of chimney ior any kind of fuel, 317. showing the results of experi- ments made on different brands of boiler-iron at the Stevens Institute of Tech- nology. Hoboken, N. J., 327. showing the rise of safety- valves, in parts of an inch, at different pressures, 181. showing the strength of weld- ed boiler-plates, 286. showing the tensile strength of various qualities of American and English cast- iron, 382, showing the tensile strength of various qualities of American wrought-iron, 333, INDEX. Table showing the _ tensile strength of various quali- ties of English wrought- iron, 384. showing the units of heat re- quired to convert 1 pound of water, at the temperature of 32° Fah., into steam at different pressures, 311. showing the weight of boiler- plates 1 foot square and from zsth to an inch thick, 830. showing the weight of cast- iron balls from 3 to 13 inches in diameter, 328. showing the weight of cast- iron, pipes, 1 foot in length, from 4 inch to 114 inches thick, and from 38 to 24 inches diameter, 331. showing the weight of cast- iron plates per superficial foot as per thickness, 328, showing the weight of round- iron from 1% an inch to 6 inches diameter, 1 foot long, 329. showing the weight of square bar-iron from ¥4 an inch to 6 inches square, 1 foot long, 330. Tensile strength, 278, Lesting-machines, 308, 347 Testing steam-boilers, 103. Theory, spheroidal, 218. Thickness of boiler materiats, 60, To polish brass, 834. Torsional strength, 278. Transverse strength, 278. Tubes, boiler, 155. diameter and arrangements of, 156. evaporative efficiency of, 158. Tubular boiler, marine, 42. boilers, 30. Tubulous boiler, Wittingham’s, 188. boilers, 85, Vagaries of experts in regard to steam-boiler explosions, 227. Vertical circulating tubular boiler, Clapp and Jones’, 69. marine boiler, 46. tubular boiler, Silsby’s, 80. Water-gauges, glass, 178, Water-space and steam-room in steain-boilers, 58. Wiegand sectional boiler, 111. Wittingham’s tubulous boiler, 188, Working strength, 279. Wrought-iron, linear expansion of, 324. Zine as an anti-crustator, 207. eens mpl cane ROPE R’S PRACTICAL HAND-BOOKS FOR ENGINEERS. Of all the efforts of human ingenuity known, perhaps none has monopolized so large a share of inventive genius | as the steam-engine. No other object in the entire range of human devices has so irresistibly arrogated to itself the devotion of scientific men as the production of an artificial movement from the vapor of boiling water. ROPER’S PRICE. Hand-Book of Land and Marine Engines. $3.50 | een aan een ROPER’S Hand-Book of the Locomotive. 2.50 ——_#e— — . ROPER’S and-Book of Modern Steam Fire-Engines. 3.50 +See ROPER’S Catechism of High-Pressure or Non=-Condensing Steam-Engines. 2.60. ROPER’S ' Engineer’s Handy-Book. 3.50 ROPER’S Instructions and Suggestions for Engineers and _ , Firemen. 2.00 ——~9e—— ROPER’S Care and Management of the Steam-Boiler. 2.00 OK , ROPER’S Simple Process for Estimating the Horse-Power of Steam-Engines. .50 ROPER’S | ; Questions and Answers for Engineers. 3.00 ROPER’S Use and Abuse of the Steam-Boiler. 2.00 DO -ROPER’S Young Engineer’s Own Book. 3.00 ee wee aes eee INTRODUCTION. HE object of the writer in preparing these works haa been to present to the practical engineer a set of books to which he can refer with confidence for information regarding every branch of his profession. Up to the date of the publication of these books, it was impossible to find a plain and practical treatise on the steam-engine, This arose, perhaps, from the fact that men who had attained proficiency in steam-engineer- ing had no taste for devoting their limited leisure time to writing, and that those whose circumstances enabled them to do so, were precluded from a want of that practical knowledge which is only obtained by years of hard work and close observation. Many of the books heretofore written on the steam-engine are full of formule for calculating questions that may arise in the engine-room; but, as they are generally expressed in algebraical form, they are of little service to the majority of engineers; for, however useful such for- mule may be to the scientific, they can be of no prac- tical value to men who do not fully understand them. It is also no less a fact, that nearly all writers on the steam-engine deal more with the past than the present. This is to be regretted, for, however interesting the by- gone records of steam-engineering may be as a history, they cannot instruct the engineer of the present day in the principles and practice of his profession. An experience of over thirty years, with all kinds of 3 | INTRODUCTION, engines and boilers, enables the writer to fully under- stand the kind of information most needed by men having charge of steam-engines of every description, and what they could comprehend and employ. With this object in view, he has carefully investigated all the details of stationary, locomotive, fire, and marine engines, taking up each subject singly, and excluding therefrom everything not directly connected with steam-engineering. Particular attention has been given to the latest improvements in all these classes of engines, and their proportioning according to the best modern practice, which will be of immense value to engineers, as nothing of the kind has heretofore been published. They also contain ample instruc- tions for setting up, lining, reversing, and setting the valves of all classes of engines—subjects that have not received that attention from other writers on the steam-engine which their importance so justly merits. A certain portion of each book is devoted to an exam- ination and discussion of the principles of Hydro- and Thermo-Dynamics, which include Air, Water, Heat, Combustion, Steam, Liquefaction, Dilatation of Gases, Molecular and Atomic Forces, Dynamic Equivalents, subjects with which the practical engineer should be fully conversant; as to ignore the principles of any subject is similar to building a structure without knowing the strength of the foundation; for it is only by a minute and careful analysis of the physical phenomena which convert heat into a motor force that the steam-engine has been brought to its present perfection. Ss. R. HAND-BOOK OF LAND AND MARINE ENGINES; INCLUDING THE MODELLING, CONSTRUCTION, RUNNING, AND MANAGEMENT OF LAND AND MARINE ENGINES AND BOILERS. Fully Hllustrated, BY STEPHEN ROPER, ENGINEER, Author of ’ Roper’s Hand-Book of Land and Marine Engines,” “ ‘Roper’s. Catechism of High-Pressure or Non- Condensing Steam-Engines,” ‘Roper’s Hand-Book of the Locomotive,” ‘‘Roper’s Hand-Book of Modern Steam Fire- Engines, ” “Roper’s Handy-Book for Engineers,’ ‘‘Roper’s Young Engineer’s Own Book,” “ Roper's Use and Abuse of the Steam-Boiler,” “Questions for Engineers,” etc. MARINE BEAM-ENGINE, PHILADELPHIA: EDWARD MEEKS. Lay ) 5 Roper’s Hand-book of Land and Marine Kngines. Opinions of the Press. Ircn Age, New York, HE author of this hand-book says, in his preface, that his object in preparing it, “has been to present to the practical inquirer a book to which he can refer with confi- dence for information in regard to every branch of his pro- fession.” Rules and directions expressed in algebraic formule are of little service to the majority of engineers, because they are not fully understood. The author, keeping this in mind, has avoided most of the points which render many of our hand-books of limited value to the practical man. He has had a long and extensive practical experience among the men for whom he writes, and understanding their wants, has pro- duced a book which seems admirably adapted to those who have anything to do, in a practical way, with steam ma- chinery. We have given the work a careful examination, and consider it one of the most satisfactory works of the kind we have ever seen. Mr. Roper thoroughly understands his subject, being entirely practical, and, at the same time, hay- ing a correct understanding of scientific principles. His chapters on the theory of steam engineering are so simple and practical that there is no mechanic in the country, how- ever ignorant he may be of higher mathematics, who cannot learn all they are intended to teach. His practical directions for the management of engines are just such as we should expect from an experienced engineer who had spent all his 6 OPINIONS OF THE PRESS. life in an engine-room, but who had learned the theory as well as the practice of his trade. They are plain and to the point, and the reader may accept them with an entire confi- dence. His descriptions of engines, pumps, and the appli- ances connected with engines, are exceedingly satisfactory, as are also his rules, which seem to be the best and simplest which could be formulated. The book has an abundance of tabular information, which seems to include all the tables that could be of any use. The engravings are good, and are just what is wanted to explain the text.. In a word, the amount and kind of information contained in this work seems to be all that could be desired. The owner of a steam-engine cannot well do without it, and no one who runs an engine should be ignorant of any part of its contents. CONTENTS, INTRODUCTION. THE STEAM-ENGINE. STEAM. Table showing the Temperature and Weight of Steam at different Pressures from one Pound per Squara Inch to 300 Pounds, and the Quantity of Steam pro- duced from 1 Cubic Inch of Water, according to Pressure. EconoMy OF WORKING STEAM EXPANSIVELY. Table of Hyperbolic Logarithms to be used in Con- nection with the above Rule. Table showing the average Pressure of Steam upon the Piston throughout the Stroke, when Cut-off in the Cylinder from } to ;4, commencing with 25 Pounds and advancing in 5 Pounds up to 180 Pounds Press- ure. Table of Multipliers by which to find the mean Press- ure of Steam at various points of Cut-off. HIGH-PRESSURE OR NON-CONDENSING STEAM-ENGINES, PoWER OF THE STEAM-ENGINE. Foreign Terms and Units for Horse-power. Table of Factors. WASTE IN THE STEAM-ENGINE. DESIGN OF STEAM-ENGINES. THE BED-PLATE. CYLINDERS. | Table showing the proper Thickness for Steam-cylin- ders of different Diameters. 8 CONTENTS. PISTONS. PISTON-RINGS. PISTON-SPRINGS. STEAM-PISTONS. SoLip PIsToNs. Table of Piston Speeds for all Classes of Engines — Stationary, Locomotive, and Marine. PISTON, CONNECTING-ROD, AND CRANK CoNNECTION. Table showing the Position of the Piston in the Cyl- inder at different Crank-angles, according to the length of Connecting-rod. Table showing length of Stroke and Number of Revo- lutions for different Piston Speeds in Feet per Minute. PISTON-RODS. CRANK-PINS. Table showing the Angular Position of the Crank-pin corresponding with the various Points in the Stroke which the Piston may occupy in the Cylinder. STEAM-CHESTS. VALVE-RODS. GUIDES. ROcK-SHAFTS. CrOss-HEADS. STEAM-PORTS. Table showing the Proper Area of Steam-ports for different Piston Speeds. SLIDE-VALVES. PROPORTIONS OF SLIDE-VALVES. LAP ON THE SLIDE-VALVE. PopPpET OR CONICAL VALVES. Table showing the Amount of “Lap” required for Slide-valves of Stationary Engines when the Steam is to be Worked expansively. CONTENTS, © LEAD OF THE SLIDE-VALVE. CLEARANCE, COMPRESSION, FRICTION OF SLIDE-VALVES, BALANCED SLIDE-VALVES. FITTING SLIDE-VALVES, SLIDE-VALVE CONNECTIONS, ECCENTRICS. ECCENTRIC-RODS. CRANKS. CRANK-SHAFTS. PILLOW-BLOCKS, OR MAIN BEARINGS. FLY-WHEELS. LINK-MOTION. PROPORTIONS OF STEAM-ENGINES ACCORDING TO THE BEST MODERN PRACTICE. SETTING UP ENGINES, DEAD-CENTRE. How TO PUT AN ENGINE. IN LINE. How To REVERSE AN ENGINE. SETTING VALVES. How To sET A SLIDE-VALVE. SETTING OUT PISTON PACKING. PISTON- AND VALVE-ROD PACKING. AUTOMATIC CUT-OFFS. GOVERNORS. THE HuUNTOON GOVERNOR. THE ALLEN GOVERNOR. THE CATARACT. WRIGHT’S HIGH-PRESSURE ENGINE. HAWKINS AND DopGk’s HIGH-PRESSURE ENGINE. WATTS AND CAMPBELL’S HIGH-PRESSURE ENGINE. THE BUCKEYE HIGH-PRESSURE ENGINE. CONTENTS. WHEELOCK’S HIGH-PRESSURE ENGINE. THE CorLiss HIGH-PRESSURE ENGINE. HAMPSON AND WHITEHILL’S HIGH-PRESSURE ENGINE. THE ALLEN HIGH-PRESSURE ENGINE. WoopRUFF AND BEACH’S HIGH-PRESSURE ENGINE, NAYLOR’S VERTICAL HIGH-PRESSURE ENGINE. WILLIAMS’ VERTICAL THREE-CYLINDER HIGH-PRESS- URE ENGINE. RopPer’s CALORIC ENGINE. HASKINS’ VERTICAL HIGH-PRESSURE ENGINE. MAssEy’s RcTARY ENGINE. PORTABLE ENGINES. How To BALANCE VERTICAL ENGINES, KNOCKING IN ENGINES. THE INJECTOR. PUMPS. FORCE-PUMPS. PISTON-PUMPS. BoILER FEED-PUMPS. STEAM-PUMPS THE ATLAS STEAM-PUMP. THE DAYTON CAM-PUMP. DIRECTIONS FOR SETTING UP STEAM-PUMPS, THE PULSOMETER. ‘JAMES WATT. CONDENSING OR LOW-PRESSURE STEAM-ENGINES. EXPLANATION, OF THE WORKING PRINCIPLES OF TH? CONDENSING ENGINE. HORSE-POWER OF CONDENSING ENGINES. THE VACUUM. MARINE STEAM ENGINES. CoMPOUND ENGINES. 11 CONTENTS. TDIRECT-ACTING ENGINES. BALANCING THE MOMENTUM OF DIRECT-ACTING EN GINES, OSCILLATING ENGINES. TRUNK ENGINES. GEARED ENGINES. BACK-ACTION ENGINES, SIDE-LEVER ENGINES. BEAM ENGINES. MARINE BEAM ENGINE. STARTING-GEAR FOR MARINE ENGINES. CONDENSERS. AIR-PUMPS. THE HYDROMETER, SALINOMETER, OR SALT-GAUGE. THE MANOMETER. THE BAROMETER. MARINE ENGINE REGISTER, CLOCK, AND VACUUM GAUGE, STEAM-GAUGES. GLASS WATER-GAUGES. THE STEAM-ENGINE INDICATOR. METHOD OF APPLYING THE INDICATOR. ForRM OF DIAGRAMS, How To KEEP THE INDICATOR IN ORDER. THE DYNAMOMETER, THE ENGINEER. MANAGEMENT OF LAND AND MARINE ENGINES. How TO PUT THE ENGINES IN A STEAMBOAT OR SHIP. SCREW-PROPELLERS. PADDLE-WHEELS. FLUID RESISTANCE. Signification of Signs used in Calculations, 12 a a a os CONTENTS, DECIMAL. Decimal Equivalents of Inches, Feet, and Yards. Decimal Equivalents of Pounds and Ounces. Useful Numbers in calculating Weights and Measures ete. Decimal Equivalents to the Fractional Parts of a Gal lon or an Inch, Units. THEORY OF THE STEAM-ENGINE, WATER, AIR. THE THERMOMETER. Comparative Scale of Centigrade, Fahrenheit, and Reaumer Thermometers. ELASstTic FLUIDs, CALORIC, HEAT, COMBUSTION, GASES. STEAM-BOILERS, STEAM-DOMES, MtUp-pRU Ms. SETTING Borers. EXPANSION AND CONTRACTION OF BoILERs. TESTING BOILERS, NEGLECT OF STEAM-BOILERS, CARE AND MANAGEMENT OF STEAM-BOILERS, HraTING SURFACE, ) RULES FOR FINDING THE HEATING SURFACE OF STEAM BOILERS. EVAPORATIVE EFFICIENCY OF BOILERS, HORSE-POWER OF BOILERS, ; a 13 CONTENTS. FIRING. INSTRUCTIONS FOR FIRING. RULES FOR FINDING THE QUANTITY OF WATER BOIL- ERS AND OTHER CYLINDRICAL VESSELS ARE CAPA- BLE OF CONTAINING. LONGITUDINAL AND CURVILINEAR STRAINS. RULES. EXPLANATION OF TABLES OF BOILER PRESSURES ON _ FOLLOWING PAGES. Table of safe Internal Pressures for Iron Boilers. Table of safe Internal Pressures for Steel Boilers. MARINE BOILERS. Proportions of Heating Surface to Cylinder and Grate Surface of noted Ocean, River, and Ferry-boat Steamers. SETTING MARINE BOILERS. BEDDING MARINE BOILERS. CLOTHING MARINE BOILERS, CARE OF MARINE BOILERS. REPAIRING STEAM-BOILERS, TUBES, Table of Superficial Areas of External Surfaces of Tubes of Various Lengths and Diameters in Square Feet, BoILER EF LUES, BOILER-HEADS. SAFETY-VALVES. Table showing the Rise of Safety-valves, in Parts of an Inch, at different Pressures, RULES. FOAMING, INCRUSTATION IN STEAM-BOILERS, 14 CONTENTS, INTERNAL AND EXTERNAL CORROSION OF STEAM- BOILERS. BoILER EXPLOSIONS. COMPARATIVE STRENGTH OF SINGLE AND DOUBLE: RIVETED SEAMS, CALKING, STRENGTH OF THE STAYED AND FLAT SURFACES. DEFINITIONS AS APPLIED TO BOILERS AND BOILER MATERIALS, FEED-WATER HEATERS, Table showing the Units of Heat required to Convert One Pound of Water, at the Temperature of 32° Fah., into Steam at different Pressures. STEAM-JACKETS. Loss OF PRESSURE IN CYLINDERS INDUCED BY LONG STEAM-PIPES. PRIMING IN STEAM-CYLINDERS. OILS AND OILING, | Table of Coefficients of Frictions between Plane Sur- aces. GRATE-BARS. CHIMNEYS. Table showing the proper Diameter and Height of Chimney for any kind of Fuel. SMOKE. MENSURATION OF THE CIRCLE, CYLINDER, SPHERE, ETC, CENTRAL AND MECHANICAL FORCES AND DEFINI- TIONS. THE CIRCLE. Table containing the Diameters, Circumferences, and Areas of Circles, and the Contents of each in Gal- lons, at 1 Foot in Depth. 15 CONTENTS. LOGARITHMS. Table of Logarithms of Numbers from 0 to 1000. HYPERBOLIC LOGARITHMS. | Table of Hyperbolic Logarithms, Table containing the Diameters, Circumferences, and Areas of Circles from ;, of an Inch to 100 Inches, RULES FOR FINDING THE DIAMETER AND SPEED OF PULLEYS. GEARING. BELTING. CEMENT FOR MAKING STEAM-JOINTS AND PATCHING STEAM-BOILERS. 5 NON-CONDUCTORS FOR STEAM-PIPES AND STEAM-CYL- INDERS. How To MArK ENGINEERS’ OR MACHINISTS’ TOOLS. To PouisH BRAss, SOLDER. Table showing Weight of different Materials. JOINTS. THE INVENTION AND IMPROVEMENT OF THE STEAM- ENGINE. re 16 : HAND-BOOK } OF THE Oe Cy NEO TE Nar. INCLUDING THE CONSTRUCTION, RUNNING, AND MANAGEMENT OF LOCOMOTIVE ENGINES AND BOILERS. Fully illustrate, BY STEPHEN ROPER, Encrneerr, Author of “ Roper’s Hand-Book of Land and Marine Engines,” “ Roper’s Catechism of High-Pressure or Non-Condensing Steam-Engines,” ‘“Roper’s Hand-Book of the Locomotive,” ‘‘ Roper’s Hand-Book of Modern Steam Fire-Engines,” ‘“Roper’s Handy-Book for Engineers,” ‘‘Roper’s Young Engineer's Own Book,” “Roper’s Use and Abuse of the Steam-Boiler,” ‘‘ Questions for Engineers,” etc. PHILADELPHIA: a EDWARD MEEKS. ; , ao | . 17 ROPER’S HAND-BOOK LHE LOCOMOTIVE: OPINIONS OF THE PRESS, Scientific American, New York. The author of this work very truly believes that in a book, ss ina clock, any complication of its machinery has a tendency to impair its usefulness and affect its reliability. Hence, in pres paring a book which is intended to be a guide for the practical locomotive engineer, he avoids “mathematical problems and entangling formule,” 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 18 ROPER’S HAND-BOOK OF THE LOCOMOTIVE, classes of steam-engines and boilers. The object of the work ia 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 exastly what the class for whom he writes require, and what they ean 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 ereated 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. If contains suitable illustrations, and is appropriately ; refaced with a portrait of M. W. Baldwin. 19 CONTENTS, INTRODUCTION. THE LOCOMOTIVE. LOCOMOTIVE ENGINEERS. THEORY OF THE LOCOMOTIVE, W ATER, AIR. COMPARATIVE SCALE OF ENGLISH, FRENCH, AND GER- MAN THERMOMETERS. THE THERMOMETER. ELAstTic FLUIDS AND VAPORS. CALORIC. HEAT. COMBUSTION. GASES, STEAM. Table showing the Velocity with which Steam of Differ- ent Pressures will flow into the Atmosphere or into Steam of lower Pressure. Rule for finding the Superficial Feet of Steam-pipe re- quired to Heat any Building with Steam. Table showing the Temperature of Steam at Different Pressures from 1 pound per Square Inch to 240 pounds, and the Quantity of Steam produced from a Cubic Inch of Water, according to Pressure. HORSE-POWER OF STEAM-ENGINES, Rule for finding the Horse-power of Stationary En- gines, THE POWER OF THE LOCOMOTIVE. 20 = r a ae ee ee eee CONTENTS. Rule for finding the Horse-power of a Locomotive. Rules for calculating the Tractive Power of Locomo- tives. Table of Gradients. Adhesive Power of Locomotives. Proportions of Locomotives, according to best Modern Practice. Proportions of Different Parts of Locomotives, accord- ing 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. LoOcoMOTIVE BUILDING. CONSTRUCTION OF LOCOMOTIVES. SETTING THE VALVES OF LOCOMOTIVES. DEAD WEIGHT IN LOCOMOTIVES. Table showing the number of Revolutions per minute made by Drivers of Locomotives of different Diam- eters and at different Speeds. STEAM-PORTS. BRIDGES. ECCENTRICS. Eccentric Rops. Formula by which to find the Positions of the Eccen- tric 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 21 CONTENTS, Valves of Locomotives in Practice, on thirty-five of the principal Railroads in this Country, THE LINK. ADJUSTMENT OF THE LINK. STEAM AND SPRING CYLINDER PACKING FOR Loco- MOTIVES, Rule for finding the size of Piston- and Valve-rod Packing, j BRASSES FOR DRIVING-AXLES OF LOCOMOTIVES. LATERAL MOTION. SPEED INDICATORS. LocoMOTIVE BOILERS. PROPORTIONS OF THE LOCOMOTIVE BOILER, FROM THE BEST MODERN PRACTICE. WAGON-TOP AND STRAIGHT BOILERS. THE EVAPORATIVE POWER OF LOCOMOTIVE BOILERS. HEATING SURFACE, STEAM ROOM, AND WATER SPACE IN LOCOMOTIVE BOILERS. HEATING SURFACE TO GRATE SURFACE IN STEAM BOILERS. Rule for finding the Heating Surface in Locomotive Boilers. Rule for finding the Heating Surface in the Tubes of Locomotive Boilers. Rule for finding the Heating Surface in Stationary Boilers. PUNCHED AND DRILLED HOLES FOR THE SEAMS OF LOCOMOTIVE BOILERS. MACHINE AND HAND RIVETING FOR LOCOMOTIVE BOILERS. COMPARATIVE STRENGTH OF SINGLE AND DOUBLE RIVETED BOILER SEAMS. 22 CONTENTS. FURNACES OF LOCOMOTIVE BOILERS. PROPORTIONS OF FIRE-BOXES, FROM THE BEST Mop- ERN PRACTICE. | STRENGTH OF STAYED SURFACES IN THE FURNACES .OF LOCOMOTIVE BOILERS. STAY-BOLTS. CROWN-BARS. TUBES. CoMBUSTION OF FUEL IN LOCOMOTIVE FURNACES. SMOKE-BOX. SMOKE-STACKS. EXHAUST-NOZZLE. SAFETY-VALVES. Tablé showing the Rise of the Safety-valves. STEAM-GAUGES. INSTRUCTIONS FOR THE CARE AND MANAGEMENT OF LOcoMOTIVE BOILERS. FIREMEN ON LOCOMOTIVES. FIRING. THE INJECTOR. SIGNALS. Wreckina Toots. RULES FOR FINDING THE ELASTICITY OF STEEL SPRINGS. CENTRAL AND MECHANICAL Forces AND D£FINI- TIONS. Table containing Diameters, Circumferences, and Areas of Circles, etc. INCRUSTATION IN STEAM-RPOILERS. BOILER EXPLOSIONS. VOCABULARY OF TECHNICAL TERMS AS APPLIED TO THE DIFFERENT PARTS OF LOCOMOTIVES, 23 HAND-BOOK OF MODERN STEAM FIRE-ENGINES. INCLUDING ‘THE RUNNING, CARE AND MANAGEMENT OF STEAM FIRE-ENGINES AND FIRE-PUMPS. BY STEPHEN ROPER, ENGINEER, AUTHOR OF “ ROPER’S CATECHISM OF HIGH PRESSURE OR NON-CONDENSING STEAM ENGINES,” “ROPER’S HAND*BOOK OF LOCOMOTIVES,” ‘+ ROPER’S HAND-BOOK OF LAND AND MARINE ENGINES,” ETO, Second Fdition, tuith Lllustrations. REVISED AND CORRECTED BY H. L. STELLWAGEN, M. E, PHILADELPHIA : EDWARD MEEKS, 1012 WALNUT STREET, 1889, CONTENTS. THE STEAM FIRE-ENGINE. FIRE. PRECAUTIONS AGAINST FIRES. WHAT TO DO IN CASE OF FIRE. MEANS OF PREVENTING FIRES. DIFFERENT METHODS OF EXTINGUISHING FIRES. FIRE-ESCAPES. FIRE PROOF BUILDINGS. LOSSES BY FIRE. AHRENS’ STEAM FIRE-ENGINE. AIR. Table showing the Weight of the Atmosphere in Pounds, Avoirdupois, on 1 Square Inch, corresponding with different Heights of the Barometer, from 28 Inches to 31 ‘Inches, varying by Tenths of an Inch. Table showing the Expansion of Air by Heat, and the Increase in Bulk in Proportion to Increase of Tempera- ture. ELASTIC FLUIDS. AIR-VESSELS. CLAPP AND JONES’ STEAM FIRE-ENGINE. WATER. Table showing the Boiling point for Fresh Water at differ- ent Altitudes above Sea-level. Table showing the Weight of Water at different Tempera- tures. Table showing the Weight of Water in Pipe of various Diameters 1 Foot in Length. Table containing the Diameters, Circumferences; and Areas of Circles, and the Contents of each in Gallons, at 1 Foot in Depth. Utility of the Table. SILSBY ROTARY STEAM FIRE-ENGINE. METHOD OF WORKING THE STEAM IN THE SILSBY ROTARY ENGINE, DISCHARGE OF WATER THROUGH APERTURES, 25 CONTENTS. Table showing the Theoretical Discharge of Water by Round Apertures of various Diameters, and under differ- ent Heads of Water Pressure. Table showing the Actual Discharge by Short Tubes of various diameters, with Square Edges and under differ- ent Heads of Water Pressure, being ;°; of the Theoreti- cal Discharge. Table showing the Discharge of Jets with different Heads. Table showing the Number of Gallons of Water discharged through different Size Apertures, and with different Heads, in One Minute and in Twenty-four Hours. RULES. STEAM FIRE ENGINES. NAMES OF PRINCIPAL MANUFACTURERS OF STEAM FIRE- ENGINES IN THIS COUNTRY. AMOSKEAG STEAM FIRE- ENGINE. EARLY FORMS OF STEAM FIRE-ENGINES. FLOATING STEAM FIRE-ENGINES. THE BUTTON STEAM FIRE-ENGINE. TRIALS OF STEAM FIRE- ENGINES. INSTRUCTIONS FOR THE CARE AND MANAGEMENT OF STEAM FIRE-ENGINES AND BOILERS. ENGINEERS. FIREMEN. USEFUL INFORMATION FOR ENGINEERS AND: FIREMEN. PAID AND VOLUNTEER FIRE DEPARTMENTS. FIRE-ALARMS. THE GOULD STEAM FIRE-ENGINE. ROUTINE OF BUSINESS IN PAID FIRE DEPARTMENTS. FIRE-HOSE. HOSE-COUPLINGS. DIMENSIONS OF FIRST- AND SECOND-CLASS aryl age FIRE- ENGINES. HORIZONTAL DISTANCES THROWN BY MODERN STEAM FIRE-ENGINES. PERPENDICULAR HEIGHTS THROWN BY MODERN STEAM- FIRE- ENGINES. THE LA FRANCE STEAM FIRE-ENGINE. HIGH-PRESSURE OR NON-CONDENSING STEAM-ENGINES-- FIRE, LOCOMOTIVE, AND STATIONARY. POWER OF THE STEAM ENGINE. 26 : CONTENTS. FOREIGN TERMS AND UNITS FOR HORSE-POWER. Table of Factors. THE POWER OR HORSE-POWER OF THE LOCOMOTIVE. RULES FOR CALCULATING THE TRACTIVE POWER OF Loco: MOTIVES. Table of Gradients. HOLLOWAY CHEMICAL FIRE-ENGINE. SELF-PROPELLING STEAM FIRE-ENGINES. WASTE IN THE HIGH-PRESSURE OR NON-CONDENSING STEAM-ENGINES. TABLE COMPARING DuTy oF MODERN HIGH-GRADE ENGINES. DIFFERENT PARTS OF STEAM ENGINES—THE CRANK. Table showing the Angular Position of the Crank-pin cor- responding with the various Points in the Stroke which the Piston may occupy in the Cylinder. Table of Piston Speeds for all Classes of Engines—Station- ary, Locomotive, Fire, and Marine. Table showing Position of the Piston in the Cylinder at different Crank-angles, according to the length of Con- necting-rod. Table showing Length of Stroke and Number of Revolu- tions for different Piston Speeds in Feet per Minute. THE ECCENTRIC. THE SLIDE-VALVE. PROPORTIONS OF SLIDE VALVES. LAP ON THE SLIDE-VALVE. Table showing Amountof ‘‘ Lap’’ required for Slide-valves of Stationary Engines when the Steam is to be Worked Expansively. LEAD OF THE SLIDE-VALVE. FRICTION OF SLIDE-VALVES. BALANCED SLIDE-VALVES. COMPRESSION. CLEARANCE. AUTOMATIC CUT-OFFS. SETTING VALVES. How To SET A SLIDE-VALVE. SETTING OUT PISTON PACKING. How To REVERSE AN ENGINE. DEAD CENTRE. 27 CONTENTS, How TO PuT AN ENGINE IN LINE. PROPORTIONS OF STEAM-ENGINES ACCORDING TO THE BEST MoDERN PRACTICE. Table showing Proper Thickness for Steam Cylinders of different diameters. : THE INVENTION AND IMPROVEMENT OF THE STEAM: ENGINE. SIGNIFICATION OF SIGNS USED IN CALCULATIONS. DECIMALS. Decimal Equivalents of Inches, Feet and Yards. Decimal Equivalents of Pounds and Ounces. Useful Numbers in Calculating Weights and Measures, ete. Decimal Equivalents to the Fractional Parts of a Gallon or an Inch. UNITS. THE METRIC SYSTEM OF MEASURES AND WEIGHTS. Metric Measures of Length. Metric Measures of Surface. Metric Measures of Capacity. Metric Weights. PUMPS. STEAM-PUMPS. BLAKE’S SPECIAL STEAM FIRE-PUMP. WRIGHT’S BUCKET-PLUNGER STEAM FIRE-PUMP. Dimensions ofthe Bucket-plunger Steam Fire-pumps. PROPORTIONS OF STEAM FIRE-PUMPS. PROPORTIONS OF BOILER FEED-PUMPS. PROPORTIONS OF MARINE-PUMPS. PROPORTIONS OF WRECKING-PUMPS. PROPORTIONS OF MINING-PUMPS. PROPORTIONS OF AIR-PUMPS. PROPORTIONS OF TANK-PUMPS. PROPORTIONS OF BREWERS’ AND DISTILLERS' PUMPS. Table showing the Proportions of Steam-pumps demon-~ strated by Practical Experience to be the best adapted for the Various Purposes for which they are used. THE KNOWLES’ STEAM FIRE-PUMP. EARLE’S STEAM FIRE-PUMP. DIRECTIONS FOR SETTING UP STEAM-PUMPS, THE ATLAS STEAM FIRE PUMP. OuNDE’S CHALLENGE STEAM FIRE-PUMP. 28 CONTENTS. HOLLY’sS ROTARY STEAM FIRE-PUMP. PROPER METHOD OF LOCATING STEAM FIRE-PUMPS. THE INJECTOR. Table of Capacities of Rue’s ‘‘ Little Giant ’’ Injector. THE PULSOMETER. THE HYDRAULIC RAM. BOILERS OF STEAM FIRE-ENGINES. CAUSES OF FOAMING IN STEAM-BOILERS. EVAPORATION IN STEAM-BOILERS. INTERNAL AND EXTERNAL CORROSION OF STEAM-BOILERS. RULES. RULE FOR FINDING THE HEATING SURFACE OF STEAM BOILERS. DEFINITIONS AS APPLIED TO BOILERS AND BOILER MATE- RIALS. Table of Safe Internal Pressures for Iron Boilers. LONGITUDINAL AND CURVILINEAR STRAINS. HEAT. LATENT HEAT OF VARIOUS SUBSTANCES. Table of the Radiating Power of different Bodies. Table showing the Effects of Heat upon different Bodies. CALORIC. COMBUSTION. COMPOSITION OF DIFFERENT KINDS OF ANTHRACITE COAL. Table showing the Total Heat of Combustion of Various Fuels. Table showing the Nature and Value of several Varieties of American Coal and Coke, as deduced from Experiments by Professor Johnson, for the United States Government. Table showing some of the Prominent Qualities in the principal American Woods. Table showing the Relative Properties of good Coke, Coal, and Wood. ENTIRE COAL PRODUCTIONS OF THE WORLD. SPONTANEOUS COMBUSTION. Table showing the Temperature at which different Com- bustible Substances will Ignite. STEAM. ECONOMY OF WORKING STEAM EXPANSIVELY. Table of Hyperbolic Logarithms to be used in connection with the above Rule. 29 CONTENTS. Table of Multipliers by which to find the Mean Pressure of Steam at Various Points of Cut-off. Table showing the Average Pressure of Steam upon the Piston throughout the Stroke, when Cut-off in the Cyl- inder from 4 to 75, commencing with 25 Pounds and advancing in 5 Pounds up to 15 Pounds Pressure. Table showing the Average Pressure of Steam upon the Piston throughout the Stroke, when Cut-off in the Cylin- der from 4 to 4, commencing with 80 Pounds, and ad- vancing in 5 Pounds up to 130 Pounds Pressure. Table showing the Temperature of Steam at different Pressures, from 1 Pound per Square Inch to 240 Pounds, and the Quantity of Steam produced from a Cubic Inch of Water, according to the Pressure. EXPLANATION OF TABLE. Table of the Elastic Force, Temperature and Volume of Steam from a Temperature of 32° to 457° Fah., and from a Pressure of 0.2 to 900 inches of Mercury. Table showing the Temperature and Weight of Steam at - different Pressures from 1 Pound per Square Inch to 300 Pounds, and the Quantity of Steam produced from 1 Cubic Inch of Water, according to Pressure. CENTRAL AND MECHANICAL FORCES AND DEFINITIONS. MENSURATION OF THE CIRCLE, CYLINDER, SPHERE, ETC. PROPERTIES OF THE CIRCLE. Table containing the Diameters, Circumferences, and Areas of Circles from 7; of an Inch to 20 Inches, advanc- ing by 7; of an Inch up to 10 Inches, and by 3} of an Inch from 10 Inches to 20 Inches. LOGARITHMS. Table of Logarithms of Numbers from 0 to 1000, HYPERBOLIC LOGARITHMS. Table of Hyperbolic Logarithms, RULES FOR FINDING THE ELASTICITY OF STEEL SPRINGS. Table showing the Actual Extension of Wrought-iron at Various Temperatures. Table deduced from Experiments on Iron Plates for Steam-boilers, by the Franklin Institute, Philadelphia. Table showing the result of Experiments made on different Brands of Boiler Iron at the Stevens Institute of Tech- nology, Hoboken, New Jersey. 30 CONTENTS. Table showing the Weight of Cast-iron Balls from 3 to 13 Inches in Diameter. Table showing the Weight of Cast-iron Plates per Super- ficial Foot as per Thickness. Table showing the Weight of Cast-iron Pipes, 1 Foot in Length, from 4 Inch to 1} Inches thick, and from 3 to 24 Inches Diaweiss Table oe. the Weight of Boiler-plates 1 Foot Square and from =. Inch to an Inch thick. Table showing the Weight of Square Bar-iron, from 3 inch to 6 Inches Square, 1 Foot long. Table showing the Weight of Round-iron from } Inch to 6 Inches Diameter, 1 Foot long. How To MARK ENGINEERS’ OR MACHINISTS’ TOOLS. To PoLIsH BRASS. SOLDER. CEMENT FOR MAKING STEAM-JOINYTS _AND PATCHING STEAM-BOILERS. JOINTS. RELATIVE VALUE OF FOREIGN AND UNITED STATES MONEY. Table showing the Load that can be Carried by Man and Animals. Man or Animal Working a Mechine. Table of Coefficients of Frictions between Plane Surfaces. Table of Friction Coefficients for different Pressures up to the Limits of Abrasion. The Prevention and Removal of Scale in Steam Boilers. 31 A CATECHISM OF High-Pressure or Non-Condensing STEAM-HNGINES; INCLUDING THE MODELLING, CONSTRUCTING, RUNNING, AND MAN- AGEMENT OF STEAM-ENGINES AND STEAM-BOILERS. With Paluable illustvations, BY STEPHEN ROPER, ENGINEER, Author of “Roper’s Hand-Book of Land and Marine Engines,” “ Roper’s Catechism of High-Pressure or Non-Condensing Steam-Engines,” “Roper’s Hand-Book of the Locomotive,” ‘‘Roper’s Hand-Book of Modern Steam Fire-Engines,” “Roper’s Handy-Boeok for Engineers,” ‘‘Roper’s Young Engineer’s Own Book,” “ Roper’s Use and Abuse of the Steam-Boiler,” ‘Questions. fur Engineers,” etc. PHILADELPHIA; EDWARD MEEKS. 35% ROPER’S CATECHISM STHAM HNGLN ES. OPINIONS OF THE PRESS, From the North American and United States Gazette, A Catechism of High-Pressure Steam En- gines, by Stephen Roper. Mr. Roper, himself @ practical engineer, has undertaken to furnish his fellow-engineers with the information experience has shown him to be most valuable. A number of tables of constant utility are furnished, and many rules and much practical advice. The work is plain rather than scientific in its language, and, claiming to be the only one expressly calculated for engineers, cannot fail to find quick demand and be of great value. From the Scientific American, A Catechism of High-Pressure or Non-Con- densing Steam Engines, by Stephen Roper, En- gineer. This isa valuable book on the steam engine It contains much needed general information for en- gineers, as well as a description of many American improvements and specialties in steam engineering 33 CONTENTS. INTRODUCTION. THE STEAM-ENGINE. WATER. AIR. HEAT. THE THERMOMETER. Comparative Scale of English, French, and German Thermometers. STEAM. Table showing the Temperature of Steam at different Pressures. THE ENGINEER. THE STEAM-BOILER. Cylinder Boilers. Flue Boilers. Tubular Boilers. Double-Deck Boilers. Locomotive Boilers. Mud-Drums. Boiler-Heads. Boiler-Shells. Steel Boilers. Internal and External Pressures. Rules. Table of Internal Pressures. Foaming in Steam-Boilers. Rust. Patent Steam-Boilers. THE SAFETY-VALVE. FEED-WATER HEATERS. FUEL. CHIMNEYS. 34 CONTENTS. SMOKE. GRATE-BARS. ]JUTIES OF AN ENGINEER IN THE CARE AND MANAGE MENT OF THE STEAM-BOILER. STEAM-ENGINES. Table showing the Average Pressure of the Steam upon the Piston throughout the Stroke. Lap on the Slide- Valve. ; Table showing the Amount of “ Lap” required for Slide-Valves when the Steam is to be worked ex- pansively. Lead on the Slide- Valve. * Cushion.” Setting Valves. Size of Steam-Port. Size of Steam-Pipe. Size of Piston-Rod. Material for Different Parts of Engines. Proportions of Engines. Reversing an Engine. Putting an Engine in Line. Setting up Engines. RULES FOR THE CARE AND MANAGEMENT OF THE _ S§TEAM-ENGINE. DIFFERENT KINDS OF ENGINES. KNOCKING IN ENGINES. VACUUM. THE INDICATOR. THE GOVERNOR. THE INJECTOR. STEAM-PUMPS. CENTRIFUGAL PUMPS. 85 CONTENTS. NOoIsELESS BoILER FEED-PUMP. Directions for Setting Up Steam-Pumps.. Table containing the Diameter, Circumferences, and Areas of Circles, and the Cubical Contents of Cyl. inders, in Gallons. PisToN-Rop PACKING. INCRUSTATION, BoILER EXPLOSIONS, STEAM- AND FIRE-REGULATOR. CENTRAL AND MECHANICAL FORCES, MENSURATION. Circle, Cylinder, Sphere, ete. BELTING. Leather Belts. Lacing Belts. Horizontal Belts. Perpendicular Belts. Greasing Belts. Rules for finding the Proper Width of Belts. RULES TO BE OBSERVED IN CASE OF ACCIDENTS, A BrieF HIsTORY OF THE STEAM-ENGINE. History of the Different Parts of the Steam-Engine in Detail. VOCABULARY OF TECHNICAL TERMS as applied to Differ- ent Parts of Steam-Engines and Steam-Boilers. PROPORTIONS of Steam-Engines according to the best modern practice. CEMENT for making Steam-Joints and patching Steam- Boilers. How to mark Engineers’ or Machinists’ Tools. To polish Brass, Non-Conpuctors for Steam-Pipes and Cylinders, € 86 oe re eo AS pe wes ie Sg ee ae we THE ENGINEER’S HANDY-BOOK. CONTAINING A FULL EXPLANATION OF THE STEAM-ENGINE INDICATOR, AND [ITS USE AND ADVANTAGES TO ENGINEERS AND STEAM USERS. WITH FORMULZ FOR ESTIMATING THE POWER OF ALL CLASSES OF STEAM-ENGINES; ALSO, FACTS, FIGURES, QUESTIONS, AND TABLES FOR ENGINEERS WHO WISH TO QUALIFY THEMSELVES FOR THE UNITED STATES NAVY, THE REVENUE SERVICE, rHE . MERCANTILE MARINE, OR TO TAKE CHARGE OF THE BETTER CLASS OF STATIONARY STEAM-ENGINES. With illustrations, BY STEPHEN ROPER, ENGINEER, Author of *Roper’s Hand-Book of Land and Marine Engines,” “ Roper’s Catechism of High-Pressure or Non-Condensing Steam-HEngines,” ‘“Roper’s Hand-Book of the Locomotive,” ‘‘Roper’s Hand-Book of Modern Steam Fire-Engines,” “Roper’s Handy-Book for Engineers,” ‘‘Roper’s Young Engineer’s Own Book,” “Roper’s Use and Abuse of the Steam-Boiler,” ‘Questions for Engineers,” etc. PHILADELPHIA: EDWARD MEEKS. 4 37 This Book treats on every branch of Steam Engineering AND Sieam-Engines of Every Description In use at the present day,— CONDENSING, NON-CONDENSING, SIMPLE, AND COMPOUND, for Whatever Purpose Employed, whether for Engineering, Manufacturing, Pumping, Loco- motion, Mining, Hoisting, or Propulsion, AND IS MORE FULLY ILLUSTRATED THAN ANY OTHER WORK EVER HERETOFORE PUBLISHED ON THE SAME SUBJECT. 38 OE a ee ey ee = ees ee OPINIONS OF THE PRESS ON Roper's Engineer's Handy-Book. The Manufacturer and Builder, New York. AN ENGINEER’s Hanpy-Boox.—Mr. Roper, the writer of this work, is well known to many of our readers as the author of a number of useful reference books relating to steam- engineering, which have become deservedly popular by reason of their plain, intelligible style, and their freedom from un- necessary and confusing mathematical technicalities. We would be glad to see Roper’s hand-books largely multiplied and distributed in every workshop, for it is only out of books of this kind that the average workman will be able to master the principles of his handiwork. Millstone, Indianapolis, Ind. < “THp ENGINEER'S Hanpy-Boox,” by Stephen Roper Engineer, is a practical treatise on the management of the steam-engine. The author says the book was “not written for the purpose of instructing engineers how to design or proportion steam-engines or boilers, but rather to inform them how to take care of and manage them intelligently.” The declaration is carried out in the plainest and most sys- tematic manner. As a text-book for students in mechanical engineering, it will be found of great value. Its illustrations and tabulated matter are zmportant features, and printed in excellent style 29 OPINIONS OF THE PRESS. National Car-Builder, New York. Roper’s ENGINEER’S HAnNDy-Boox.—This compact and comprehensive little volume contains a vast amount of in- formation relative to the care and management of every class of steam-engines. It is profusely illustrated, and abounds in facts, figures, rules, tables, questions and answers, formule, etc., that are exceedingly valuable to engineers, and of easy reference by means of a copious and well-arranged index. The various subjects are discussed with brevity and clearness, and with a freedom from technicality which enables the reader to get at the pith of the matter without fishing it out from an ocean of words. A prominent feature of the book is a full explanation of the steam-engine indicator, and its use and advantages to engineers and others. Leffel’s Illustrated News, Springfield, Ohio. ENGINEER’S Hanpy-Boox: By Stephen Roper, Engineer. —The author of the valuable series of hand-books which we have before referred to, has just issued the above-named work, which must find ready way into the hands of engineers and steam-users throughout the entire land. It contains a full explanation of the steam-engine indicator, its uses and ad- vantages, with formulee for estimating the power of all classes of steam-engines; also facts, figures, questions, and tables for engineers who wish to qualify themselves for the United States navy, the revenue service, the merchant marine, or the better class of stationary engines. The American Engineer, Chicago, Ill. THE ENGINEER'S Hanpy-Book.—We are in receipt of the above work, which contains a description of the various forms of engines now in use, and supplies interesting and useful information as to the care, management, and remedy of defects of steam machinery and its appendages, with tables for calculating the power of engines. 40 OPINIONS OF THE PRESS. American Machinist, New York. Roprer’s ENGINEER’s Hanpy-Boox.—The subjects in this work have been treated in a brief and comprehensive way, therefore the reader is not required to read a number of chapters in order to acquire a little knowledge. The use of the indicator is’ treated in a plain, practical way, so that it may be readily understood. Abstruse formulas have been omitted and simple arithmetic used, thus avoiding the usual vexations among practical men who are uneducated in the higher mathematics. The author has in this book given the results of his own practical experience, which extenus over a period of thirty years and upwards, and the work will deubtless be read with pleasure and profit by very many practical mechanics. Engineering News, New York. An “ ENGINEER'S HANDY-Boox.”—Asa writer on subjects relating to steam and steam-engineering, Mr. Roper is now too well known to need any further introduction. In this, his latest contribution to steam-engineering literature, Mr. Roper has aimed to present to his brother engineers a “ handy book ” that will be to them what Trautwine’s “‘ Pocket-Book” is to civil engineers, and in duing this he has spared no labor in collecting and editing his materials. Some idea of the completeness of the work may be gathered from the state- ment of the publishers that it contains nearly 300 main sub- jects, 1316 paragraphs, 876 questions and answers, 52 sugges tions and instructions, 105 rules, formule, and examples, 149 tables, 164 illustrations, 31 indicator diagrams, and 167 tech. nical ierms; over 3000 different subjects. Boston Journal of Commerce. Mr. SterpHEen RopER is well known as the author of several] other handy-books that treat on steam, steam-boilers, and engines. This new work is, in our judgment, his best. 4% Al OPINIONS OF THE PRESS. The Scientific American, New York. A WELL made pocket-book of practical information for me: ¢, anical engineers, particularly those of limited education, ard such as may wish to qualify themselves for service in the U.S. Navy or the mercantile marine. The more impor- tant engines in use are clearly described, and formule are given for estimating their power. Particular attention is paid to the steam-engine indicator, its use and advantages. The author has had much experience in this class of work, and writes clearly and plainly. The Locomotive, Hartford, Conn. Roper’s ENGINEER’S HAnpy-Boox.—This last work of Mr. Roper is of special value to all who have to do with steam-hoilers and engines, and it will be found a valuable shop companion for the mechanic. There are a great many facts collated that are not easily reached except through ex- pensive books and libraries. These will be found of service to all classes of men, whether in trade or manufacturing. We commend it heartily, and believe it will have a large sale. Forest, Forge, and Farm, llion, N. Y. ENGINEER’s HANpby-Book.—We have received a book with the above title, by the well-known author and engineer, Stephen Roper, who has written a number of works on the subject of engineering. The eminent reputation of the author is a sufficient guarantee that the book is both inter- esting and useful. Mr. Roper has had an experience of over thirty-five years with all kinds of engines and boilers, and thoroughly understands locomotive, fire, marine, and station: ary engines. 42 CONTENTS. THE ENGINEER. FACTS THAT SHOULD BE BORNE IN MIND BY ENGI: NEERS. STEAM-ENGINEERING AS A SCIENCE. EXAMINATION OF CANDIDATES FOR CADET ENGI- NEERS IN THE U. S. Navy. INSTRUCTIONS HOW TO PREPARE FOR. EXAMINATION FOR ENGINEER IN THE U.S. NAVY AND REVENUE SERVICE, INSTRUCTIONS HOW TO OBTAIN AN ENGINEER’S Li- CENSE IN THE MERCANTILE MARINE SERVICE. INSTRUCTIONS HOW TO PROCURE A LICENSE TO TAKE CHARGE OF STATIONARY ENGINES IN ANY STATE OR CITY REQUIRING IT. THE STEAM-ENGINE INDICATOR; ITs CoNsTRUC- TION AND UTILITY. DIFFERENT KINDS OF INDICATORS. FUNCTIONS OF THE INDICATOR. TECHNICAL TERMS EMPLOYED IN CONNECTION WITH THE INDICATOR. How To ATTACH THE INDICATOR. MOTION OF THE PAPER ON THE DRUM OF THE IN: DICATOR, 43 CONTENTS. Most CorreEcT METHOD OF ADJUSTING THE INDICA: TOR. Most RELIABLE PARTS OF THE STEAM-ENGINE TO WHICH TO ATTACH THE INDICATOR. How To ACCURATELY TEST THE ATTACHMENTS OF THE INDICATOR. THE INDICATOR DIAGRAM. THE EXPLANATORY DIAGRAM. THE THEORETIC DIAGRAM. THE AcTuAL DIAGRAM. ANALYSIS OF THE DIAGRAM, ANALYSIS OF THE DIAGRAM SIMPLIFIED, ANALYSIS OF THE DIAGRAM MADE EFAsy. DIAGRAMS TAKEN FROM AUTOMATIC CUT-OFF EN: GINES. DIAGRAMS TAKEN FROM THROTTLING ENGINES. DIAGRAMS TAKEN FROM COMPOUND ENGINES. DIAGRAMS TAKEN FROM SIMPLE ENGINES. DIAGRAMS TAKEN FROM LOCOMOTIVES. DIAGRAMS TAKEN FROM CONDENSING ENGINES. INSTRUCTIONS FOR MAKING AN ANALYSIS OF DIA- GRAMS. INSTRUCTIONS HOW TO SPACE THE ORDINATES. THE THEORETICAL EXPANSION CURVE. i APPLICATION OF THE ‘THEORETICAL EXPANSION CURVE. How To DRAW THE THEORETICAL EXPANSION CURVE. How To LOCATE THE THEORETICAL TERMINAL PRESS- URE. How TO CALCULATE THE MEAN EFFECTIVE PRESS: URE. 44 CONTENTS. How To CALCULATE THE THEORETICAL ECONOMY BY THE DIAGRAM. How To CALCULATE THE THEORETICAL RATE OF WATER CONSUMPTION BY THE DIAGRAM. How TO MAKE ALLOWANCE FOR CUSHION AND CLEARANCE, How To ESTIMATE THE EFFECTIVE COMPRESSION. WHat INDICATOR DIAGRAMS SHOW. THE PLANIMETER. STEAM. SUPERHEATED STEAM. TEMPERATURE OF STEAM. VOLUME OF STEAM. . SURCHARGED STEAM. EVAPORATION OF STEAM. RE-EVAPORATION OF STEAM. LATENT HEAT OF STEAM. SENSIBLE HEAT OF STEAM. HEAT NECESSARY TO GENERATE STEAM. THE QUANTITY OF WATER NECESSARY TO CONDENSE A CERTAIN QUANTITY OF STEAM. TABLES OF VOLUMES OF STEAM FOR DIFFERENT PRESSURES. WEIGHT OF STEAM. EFFLUENT VELOCITY OF STEAM AT DIFFERENT PRESS . URES. STEAM WORKED EXPANSIVELY. STEAM-J ACKETS. STEAM-DOMES. STEAM-JETS. STEAM-CHIMNEYS. CONTENTS, RELATIVE VOLUME OF STEAM AT DIFFERENT PRESS- URES. RELATIVE VOLUME OF STEAM TO THE WATER FROM WHICH IT WAS GENERATED. RELATIVE QUANTITY OF WATER REQUIRED TO CoNn- DENSE STEAM. STEAM GENERATED FROM FRESH AND SALT WATERS. CONDENSATION OF STEAM IN STEAM-CYLINDERS AND PIPES. QUANTITY OF STEAM REQUIRED FOR HEATING PUR- POSES. STEAM AS A MEANS OF PUTTING OUT FIRES, THE EXPANSIVE PROPERTIES OF STEAM. STEAM-ENGINES. PECULIARITIES OF DESIGN AND CONSTRUCTION OF THE ENGINES OF THE DIFFERENT LINES OF STEAMSHIPS PLYING BETWEEN THE DIFFERENT PoRTS OF THIS COUNTRY AND THOSE OF OTHER PARTS OF THE WORLD, WITH DESCRIPTIONS OF THE SAME, PECULIARITIES OF DESIGN AND CONSTRUCTION OF ALL THE DIFFERENT AUTOMATIC CUT-OFF STA- TIONARY ENGINES OF THIS COUNTRY, WITH DE- SCRIPTIONS. THE DIFFERENCE BETWEEN AUTOMATIC CUT-OFF AND THROTTLING ENGINES. THE ADVANTAGES OF AUTOMATIC CUT-OFF ENGINES OVER THROTTLING, AND VICE VERSA. THE ADVANTAGES OF LARGE STEAM-ENGINES OVER SMALL ONES, AND VICE VERSA. THE ADVANTAGES OF HORIZONTAL ENGINES OVER VERTICAL, AND VICE VERSA. 46 CONTENTS. THE ADVANTAGES AND DISADVANTAGES OF THE DIFFERENT STEAM-ENGINE CUT-OFFS, VIZ:, THE AUTOMATIC, POSITIVE, ADJUSTABLE, AND RIDING. A DESCRIPTION OF ALL THE CUT-OFFS IN USE ON STATIONARY AND MARINE ENGINES AT THE PRESENT Day. THE ADVANTAGES OF DIFFERENT CUT-OFFS OVER EAacH OTHER. THE Causes Most LIKELY TO INDUCE SOME STEAM- ENGINES TO DEVELOP LESS POWER THAN THEY OUGHT TO DO, WHILE OTHERS WOULD DEVELOP MORE. PROPORTIONS OF ALL THE DIFFERENT ENGINES IN UsE AT THE PRESENT Day, ACCORDING TO AC- CURATE SCALE. THE Two CLASSES OF ENGINES IN Most GENERAL USE IN THE WORLD. THE ADVANTAGES OF THE CONDENSING OVER THE Non-CONDENSING ENGINE, AND VICE VERSA. THE DIFFERENCE BETWEEN SIMPLE AND COMPOUND ENGINES, THEIR ADVANTAGES AND DISADVAN- TAGES. : How THE POWER OF ANY STEAM-ENGINE MAY BR INCREASED WITHIN CERTAIN LIMITS. THE QUANTITY OF FUEL IT WILL REQUIRE TO DE- VELOP A HorSE-POWER IN DIFFERENT ENGINES, THE QUANTITY OF WATER THAT WILL PRODUCE A HorsE-POWER IN THE MOST IMPROVED STEAM: ENGINES, AS WELL AS THE QUANTITY REQUIRED FOR THOSE OF INFERIOR TYPE. THE DIFFERENCE IN PoINT OF ECONOMY BETWEEN CONDENSING AND NON-CONDENSING ENGINES. AT CONTENTS. THE DIFFERENCE IN First Cost, Cost or MAINTEN: ANCE BETWEEN CONDENSING AND NoN-CONDENS ING ENGINES. THE ADVANTAGES AND DISADVANTAGES OF FAST AND Stow SPEED ENGINES. WHY CERTAIN TYPES OF ENGINES HAVE BEEN ABAN: DONED, AND OTHERS ADOPTED. HiGH-PRESSURE COMPOUND ENGINES. LOW-PRESSURE COMPOUND ENGINES. SCHEMES FOR REVOLUTIONIZING THE ECONOMY OF STEAM-ENGINES. | STEAM-ENGINE ECONOMY. INSTRUCTIONS FOR PLACING STEAM-ENGINES IN STEAMSHIPS, TuG- AND FERRY-BOATS. INSTRUCTIONS FOR SETTING Up, LINING, AND RE- VERSING STATIONARY STEAM-ENGINES. RuLES FOR ESTIMATING THE POWER OF STEAM- ENGINES BY FORMULZ, AND BY INDICATOR Dt- AGRAMS. RULES FOR FINDING THE RIGHT SIZE ENGINE TO DO A CERTAIN AMOUNT OF WORK. RULE FOR FINDING THE SIZE OF THE CYLINDER FOR AN ENGINE OF ANY POWER, WHEN THE PRESS- URE AND TRAVEL OF THE PISTON ARE KNOWN, RULE FOR FINDING THE QUANTITY OF STEAM ANY ENGINE WILL REQUIRE. RULES FOR THE CARE AND MANAGEMENT OF ALL CLASSES OF STEAM-ENGINES, STEAM-ENGINE GOVERNORS. SLIDE- VALVES, LAP ON THE SLIDE- VALVE, LEAD ON THE SLIDE-VALVE. 48 CONTENTS, How To TELL THE AMOUNT OF LAP AND LEAD OR A SLIDE-VALVE WITHOUT OPENING THE STEAM- CHEST. TABLE SHOWING THE AMOUNT OF LAP REQUIRED FOR ANY DESIRED CUT-OFF, RULE FOR FINDING THE AMOUNT OF LAP NECESSARY FOR ANY DESIRED CUT-OFF. How To Set A SLIDE-VALVE ACCURATELY. FRICTION OF SLIDE- VALVES, BALANCED SLIDE- VALVES, PuPPET-V ALVES, DouBLE-BEAT VALVES. THROTTLE-V ALVES, RELIEF-V ALVES. RoTAaRY- V ALVES, SEMI-ROTARY OR OSCILLATING- VALVES. BASKET-VALVES. GRIDIRON- V ALVES, VALVE-GEAR. KELEASING VALVE-GEAR. INDEPENDENT VALVE-GEAR. KXPANSION VALVE-GEAR. REVERSING VALVE-GEAR. WHOLE-STROKE VALVE-GEAR, VOCABULARY OF TECHNICAL TERMS AS APP) ,.£D TO THE DIFFERENT PARTS °F THE VALVE-G&AR OF STEAM-ENGINES. Srop-Cocks, VALVES, AND PIPES FOR WHATEVER PurRPosE EMPLOYED IN CONNECTION WITH STEAM-ENGINES, Brp-PLATES AND Hovusinas, STEAM-CYLINDERS. 5 49 CONTENTS. OYLINDER-HEAD BOLts. STEAM-PISTONS. SPRING-PISTONS. PIsTON-Rops. STUFFING- BOXES. STEAM- AND EXHAUST-PIPES, ROcK-SHAFTS. Cross-HEADS. EccENTRICS. CRANKS. CRANK-PIN BEARINGS. CRANK-SHAFT JOURNALS. Keys, JIBS, AND STRAPS. ELY- WHEELS. THE LINK FULLY ILLUSTRATED AND EXPLAINED. SHIFTING LINKS. STATIONARY LINKS. CONDENSERS, SURFACE, AND JET, : PROPORTIONS OF CONDENSERS. ADVANTAGES AND DISADVANTAGES OF DIFFERENT CONDENSERS, RELATIVE QUANTITIES OF WATER REQUIRED FOB THE Two METHODS OF CONDENSATION. THE INJECTOR CONDENSER. KortTING’s JET-CONDENSER. THE VACUUM. How THE VACUUM 18 MEASURED. How THE VACUUM IS MAINTAINED. How THE VACUUM Is PRODUCED, Tne EFFECT OF THE VACUUM. AIR-PUMPS. 50 ¥ CONTEN'SS. CAPACITY OF AIR-PUMPsS ACCORDING TO BEST Mon _ ERN PRACTICE. RELATIVE PROPORTION OF AIR-PUMP CYLINDERS TO THE CYLINDERS OF MODERN STEAM-ENGINES. CIRCULATING PUMPS. DIFFERENT KINDS OF CIRCULATING PUMPS. RELATIVE PROPORTIONS OF CIRCULATING PUMPS. MARINE PUMPS. WRECKING PUMPS. THE SALIOMETER. BAROMETER GAUGES. THERMOMELERS, MARINE-ENGINE REGISTERS. Sprinc, Mercury, SYPHON, AND VACUUM GAUGES, TABLE OF RHOMBS, OR POINTS OF THE COMPASS, TECHNICAL TERMS AND DEFINITIONS USED IN NAvV- IGATION. TABLES OF KNOTS AND MILES AS MEASURED BY VARiIous NATIONS, TABLE OF LEAGUES AND MILES. LENGTH OF THE DAY AT DIFFERENT PARTS OF THE WorLD. SAILING DISTANCE IN GEOGRAPHICAL MILES FROM New YORK TO DIFFERENT POINTS ON THR GLOBE. LATITUDE AND LONGITUDE OF DIFFERENT PLACES. MARINE SIGNALS. MARINE BELL, WHISTLE, AND LIGHT SIGNALS, RAILROAD SIGNALS, PuMPs. -FEED-PUMPS: THEIR CAPACITY, ETC. INJECTORS: THEIR CAPACITY, EFFICIENCY, ETO, 51 CONTENTS. SCREW-PROPELLERS. THE SCREW AS A MEANS OF PROPULSION. DIFFERENT KINDS OF SCREW-PROPELLERS. THRUST-BLOCKS. STERN-TUBES. PADDLE-W HEELS. DIFFERENT KINDS OF PADDLE-WHEELS. COMPARATIVE EFFICIENCY OF SCREW-PROPELLERS AND PADDLE- WHEELS. Arr: Irs WEIGHT, HEIGHT, EFFECT, ETC. TABLE SHOWING THE WEIGHT OF THE ATMOSPHERE AT DIFFERENT ALTITUDES ABOVE SEA LEVEL. TABLE SHOWING THE FORCE OF THE WIND. TABLE SHOWING THE RELATIVE VOLUME OF AIR AT DIFFERENT TEMPERATURES. FUEL. DIFFERENT KINDS OF FUEL: THEIR COMPARATIVE VALUE, ETC. THE CHEMICAL CONSTITUENTS OF DIFFERENT KINDS OF FUEL. HEAT. EFFECTS OF HEAT. CAPACITY OF DIFFERENT BODIES FOR HEAT, DIAMETERS, CIRCUMFERENCES, AND AREAS OF CIR- CLES. METALS AND ALLOYS. MARINE BOILERS. ’ DIFFERENT KINDS OF MARINE BOILERS. VOCABULARY OF TECHNICAL TERMS AS APPLIED TO. DIFFERENT PARTS OF MARINE BOILERS. VOCABULARY OF TECHNICAL TERMS AS APPLIED TO DIFFERENT PARTS OF MARINE ENGINES. 52 CONTENTS. SuPER-HEATERS. FEED-WATER HEATERS. FUNNELS. SMOKE-STACKS. AIR-CASINGS. BLAST-PIPEs, SPANNER-GUARDS. MEANING OF THE TERM MEAN EFFECTIVE PRESSURE, MEANING OF THE TERM AVERAGE PRESSURE. DIFFERENCE BETWEEN MEAN EFFECTIVE AND AVER- AGE PRESSURE. DIFFERENCE BETWEEN BOILER PRESSURE AND PRESS- URE PER GAUGE. DIFFERENCE BETWEEN BOILER AND CYLINDER PRESS- URES. ; CAUSES OF DECREASE OF PRESSURE BETWEEN BOIL- ERS AND CYLINDERS. CAUSES WHY BOILER PRESSURES DO NOT REPRESENT CYLINDER PRESSURES. THE PROBABLE AVERAGE PRESSURE IN ANY STEAM- CYLINDER AS COMPARED WITH THE BOILER PRESSURE, Wuy BorLerR PRESSURES CANNOT BE REALIZED IN THE OYLINDERS OF STEAM-ENGINES. MISTAKES IN EMPLOYING BOILER PRESSURES IN Es- ‘TIMATING THE POWER OF STEAM-ENGINES. TABLES OF CIRCUMFERENCES, DIAMETERS, AND ARBAS OF CIRCLES FROM 4 TO 100 INCHES. TABLES OF LOGARITHMS FROM 0 TO 1000. TABLES OF HYPERBOLIC LOGARITHMS, Use oF LOGARITHMS. UtirstTy OF LOGARITHMd 5* 53 CONTENTE. GEOMETRY. ‘tT RIGONOMETRY. MENSURATION, NAVIGATION. GEOGRAPHY. NATURAL PHILOSOPHY. AXIOMS. THEOREMS. PROPOSITIONS. SOLUTIONS. COROLLARIES. TABLES OF SQUARES, CUBES, AND CUBE-RooTs NUMBERS FROM 1 To 1000. MEANING OF THE TERM “ CUBED.” MEANING OF THE TERM “SQUARED.” MEANING OF THE TERM “ QUOTIENT.” MEANING OF THE TERM “ PRODUCT.” ADDITION, SUBTRACTION. MULTIPLICATION. DIVISION. PROPORTION. CoMMON FRACTIONS. DECIMALS. ‘TRIANGLES. EQUILATERAL. [SOSCELES, SCALENE, ACUTE. OBTUSE. RicgHt ANGLE, EY. 54 OF CONTENTS. THE CENTENNIAL CORLISS ENGINE, WRIGHT’s AUTOMATIC CuT-OFF ENGINE. THE Wooppury, BootH & PRYOR’s AUTOMATIC CuT-OFF ENGINE. DOUBLE-SLIDE VALVES. SEMI-ROTARY VALVES. THE BROWN AUTOMATIC CUT-OFF ENGINE. THE HARRIS CORLISS ENGINE. MARINE ENGINES. ; MODERN MARINE COMPOUND ENGIIES, SECTIONS OF MARINE COMPOUND ENGINES. SECTION OF SLIDE-VALVE ENGINE. TEE WoopRUFF & BEACH AUTOMATIC CUT-OFF HIGH-PRESSURE ENGINE. EXPANSION GEARS. THE PUTNAM MACHINE COMPANY’s AUTOMATIC CuT-OFF ENGINE. THE GREEN AUTOMATIC CuT-OFF HIGH-PRESSURE ENGINE. THE DOUGLASS AUTOMATIC CUT-OFF ENGINE. THE BABBITT & HARRIS STEAM-PISTON. PISTON, CONNECTING-ROD, AND CRANK-CONNEC- TION. THe REYNOLDS CORLISS ENGINE. Tuoi CRANK. THE LINK. VALVE-GEARS. s THE WATERTOWN AUTOMATIC CUT-OFF ENGINE. THE WATERS GOVERNOR. THE SHIVE GOVERNOR. REVERSING-GEAR FOR STEAM-ENGINES. DIAGRAMS OF SLIDE-VALVE. 55 CONTENTS. WHEELOCK’S AUTOMATIC CuT-OFF ENGINE. SECTION OF THE CYLINDER, PISTON, STEAM- AND EXHAUST- VALVES OF WHEELOCK’S AUTOMATIC CuT-OFF ENGINE. POPPET VALVES. SLIDE-V ALVES. THE WELLS Two-PISTON BALANCE-ENGINE. SECTION OF THE WELLS TWwo-PISTON BALANCE- ENGINE. THE WARDWELL VALVELESS ENGINE. THE STEAM-ENGINE INDICATOR. SECTION OF THE INDICATOR. THOMPSON’S INDICATOR. RICHARDS’ PARALLEL MOTION /.W_U1laTOR. THE ATLAS CORLISS ENGINE. INDICATOR DIAGRAMS, THE PLANIMETER. DIAGRAM MEASURED BY THE -LANIMETER. THE PoRTER-ALLEN HIGH-SpvED ENGINE. END VIEW OF A SURFACE CONDENSER. THE INJECTOR CONDENSER. INDEPENDENT CONDENSER AND AIR-PUMP. INDEPENDENT AIR- AND CIRCULATING-PUMP, WITH AIR-PUMP AT ONE END, CIRCULATING-PUMP AT THE OTHER, AND STEAM-CYLINDER IN THE MIDDLE. SECTION OF MARINE AIR-PUMP. INDEPENDENT MARINE CIRCULATING-PUMP, MARINE WRECKING-PUMP. THE SALINOMETER. THE HOTWELL THERMOMETER. THE UPTAKE THERMOMETER. 56 CONTENTS. MARINE STEAM-ENGINE REGISTER, SPRING STEAM-GAUGES. MARINE WHISTLE SIGNALS, MARINE LIGHT SIGNALS, MARINE BELL SIGNALS. RAILROAD SIGNALS, PUMPS. WILLIAM SELLERS & Co.’s LIFTING INJECTORS. SECTION OF WILLIAM SELLERS & Co.’s LIFTING INJECTOR. RvuE’s ‘‘ LITTLE GIANT”? INJECTOR. FRIEDMAN’S INJECTOR. THE KEYSTONE INJECTOR. THE ECLIPSE INJECTOR. THE CLIPPER ADJUSTABLE INJECTOR, SECTION OF CLIPPER INJECTOR. MACK’S FIXED-N0OZZLE INJECTOR. THE INSPIRATOR. THE EJECTOR OR LIFTER. JAMISON’S STEAM WATER-EJECTOR. WATER-TUBULAR MARINE-BOILER. FIRE-TUBULAR MARINE-BOILER. DIRECT FLUE AND RETURN TUBULAR MARINE- BOILER. METHOD OF BRACING MARINE STEAM-BOILERS. THE BUCKEYE AUTOMATIC HIGH-PRESSURE CUT- OFF ENGINE, DIAGRAMS OF CIRCLES, THE WETHERILL CORLISS ENGINE. DIAGRAM OF STEAM-JOINTS. THE FITCHBURG STEAM-ENGINE. THE FITCHBURG GOVERNOR. . 57 . CONTENTS, THE ENGINEER’S HANDY-BOOK CONTAINS NEAR- LY 300 MAIN SUBJECTS, 1816 PARAGRAPHS, 876 QUESTIONS AND ANSWERS, 52 SUGGESTIONS AND INSTRUCTIONS, 105 RULES, FORMUL2, AND EXx- AMPLES, 149 TABLES, 195 ILLUSTRATIONS, 31 INDI- CATOR DIAGRAMS, AND 167 TECHNICAL TERMS; OVER 3000 DIFFERENT SUBJECTS, WITH THE QUES- TIONS MOST LIKELY TO BE ASKED WHEN UNDER EX- AMINATION, BEFORE BEING COMMISSIONED AS AN ENGINEER IN THE U.S. NAVY OR REVENUE SER- VICE; BEFORE BEING LICENSED AS AN ENGINEER IN THE MERCANTILE MARINE SERVICE, OR RE- CEIVING A CERTIFICATE TO TAKE CHARGE OF A STEAM-ENGINE OR BOILER IN LOCATIONS WHERE SUCH CERTIFICATE IS NECESSARY. THERE IS NOT A SUBJECT WITHIN THE WHOLE RANGE OF STEAM- ENGINEERING ON WHICH IT DOES NOT TREAT. WITH A GREAT VARIETY OF OTHER INFORMATION NOT TO BE FOUND IN ANY OTHER BOOK EVER PUB- LISHED ON THE SAME SUBJECT IN THIS COUNTRY OR IN EUROPE, AND MORE FULLY ILLUSTRATED THAN ANY OTHER WORK EVER PUBLISHED ON THIS SUBJECT. 35 USE AND ABUSE OF THE STEAM-BOILER. BY SPrEPHEN ROPER) ENGINEER, Author of “Roper’s Hand-Book of Land and Marine Engines,” “ Ropers Catechism ef High-Pressure or Non-Condensing Steam-Engines,” “Roper’s Hand-Book of the Locomotive,” ‘‘Roper’s Hand-Book of Modern Steam Fire-Engines,” “Roper’s Handy-Book for Engineets,” ‘‘Roper’s Young Engineer’s Own Book,” “Roper’s Use and Abuse of the Steam-Boiler,” ‘Questions for Engineers,” ete. PHILADELPHIA: EDWARD MEEKS. 59 Use and Abuse of the Steam-Boiler. OPINIONS OF THE PRESS. Engineering News, Chicago, Ill. Mr. RoPER is the author of several well-known hand-books relating to the steam-engine, and steam machinery in general. In this, his latest work, he states that his object is, ‘‘ simply to show what the results of his thirty years’ personal experience with all classes of boilers prove to be the safest and most dura- ble materials for their manufacture; to show the absolute ne- cessity of good workmanship in their construction, and to call the attention of owners, engineers, and firemen to the rules that limit their usefulness, safety, and longevity.” As in all his other hand-books, the writer addresses himself to men of ordi- nary intelligence,— those found in charge of steam-engines and boilers,—and in consequence his book is written in the plainest and most intelligible language that can be chosen. We have not the time, nor possibly the necessary amount of practical knowl- edge of all the latest improvements in steam-boilers, to criticise slosely and intelligently the contents of the book, but in con- nection with it we would call attention to the large number of boiler explosions, attended with great loss of life, that have recently occurred in this country and in England, and which, upon investigation, have been proven to be the results of igno- rance and carelessness on the part of attendants ; and we cannot but think that steam-users would find it greatly to their advan- tage if such plain handy-books as those of Mr. Roper’s were placed in the hands of every attendant upon a steam-boiler or engine, and his attention called to the advantage of making himself familiar with its contents. 60 CONTENTS. ADJUNCTS OF THE STEAM-BOILER STEAM-BOILERS DESIGN OF STEAM-BOILERS FoRMS OF STEAM-BOILERS THE PLAIN CYLINDER BOILEB THE FLUE BOILER THE TUBULAR BOILER THE DOUBLE-DECK BOILER THE DROP-FLUE BOILER THE LOCOMOTIVE BOILER FIRE-BOX BOILERS TUBULOUS BOILERS S1zE OF BOILERS SECTIONAL STEAM-BOILERS MARINE BOILERS Table showing the Number of Square Feet of Heating Surface to 1 Square Foot of Grate Sur- face in the Boilers of noted Ocean, River, and Ferry-boat Steamers BOILER-HEADS STEAM-DOMES MUD-DRUMS WATER-SPACE AND STEAM-ROOM INSTEAM-BOILERS 6 61 CONTENTS. DIAMETER AND LENGTH OF STEAM-BOILERS AND THICKNESS OF BOILER-PLATE EVAPORATION IN STEAM-BOILERS EVAPORATIVE EFFICIENCY OF STEAM-BOILERS CLAPP AND JONES’ VERTICAL CIRCULATING TUBU- LAR BOILER METHODS OF TESTING THE EVAPORATIVE EFFI- CIENCY OF STEAM-BOILERS PROPORTION OF GRATE SURFACE TO HEATING SURFACE INTERNAL AND EXTERNAL CORROSION OF STEAM- BOILERS INTERNAL GROOVING IN STEAM-BOILERS SILSBY’s VERTICAL TUBULAR BOILER EXPANSION AND CONTRACTION OF BOILERS HEATING-SURFACE OF STEAM-BOILERS Rules for finding the Heating-surface of Steam- boilers THE LATTA STEEL COIL-BOILER HORSE-POWER OF STEAM-BOILERS THE MOORHOUSE SAFETY SECTIONAL BOILER SETTING STEAM-BOILERS TESTING STEAM-BOILERS . REPAIRING STEAM-BOILERS NEGLECT OF STEAM-BOILERS THE WIEGAND SECTIONAL BOILER SAFE WORKING PRESSURE OF STEAM-BOILERS Table of Safe Internal Pressures for Steel Boilers. Table of Safe Internal Pressures for Iron Boilers. THE ROGER’S AND BLACK BOILER SELECTION OF STEAM-BOILERS. PULSATION IN STEAM-BOILERS Prerce’s RoTary TuRULAR BOILER a> CONTENTS, LOcATION OF STEAM-BOILERS THE HARRISON BOILER BOILER-FLUES Table of Squares of Thickness of Iron, and Con- stant Numbers to be used in finding the Safe External Pressure for Boiler-flues Table of Safe Working External Pressures on Flues 10 Feet long Table of Safe Working External Pressures on Flues 20 Feet long COLLAPSING PRESSURE OF W ROUGHT-IRON BOILER- FLUES } INCH THICK COLLAPSING PRESSURE OF W ROUGHT-IRON BOILER- FLUES ;; INCH THICK COLLAPSING PRESSURE OF WROUGHT-IRON BOILER- FLUES $ INCH THICK COLLAPSING PRESSURE OF W ROUGHT-IRON BOILER- FLUES 7 INCH THICK THE SHAPLEY BOILER BorLER TUBES THE PHLEGER BOILER Tables of Superficial Areas of External Surfaces of Tubes of Various Lengths, Diameters in Square Feet Table of Superficial Areas of Tubes of different Lengths.and Diameters from 23 to 8 Inches and from 8 to 20 Feet STEAM-BOILER CONNECTIONS AND ATTACHMENTS. GAUGE-COCKS STEAM-GAUGES GuLAss WATER-GAUGES THE BABCOCK AND WILCOX’s SECTIONAL STEAM: BOILER . 63 CONTENTS, SAFETY-VALVES Table showing the Rise of Safety-valves, in parts of an Inch at different Pressures Table of Comparison between Experimentai Results and Theoretical Formule RULES WITTINGHAM’S TUBULOUS BOILER FOAMING IN STEAM-BOILERS INCRUSTATION IN STEAM-BOILERS PREVENTION AND REMOVAL OF SCALE IN STEAM: BOILERS STEAM-BOILER EXPLOSIONS EXPERIMENTAL BOILER EXPLOSIONS THE Roor BoILeR VAGARIES OF EXPERTS IN REGARD TO STEAM. BOILER EXPLOSIONS DEFECTS IN THE CONSTRUCTION OF STEAM-BOILERS, IMPROVEMENTS IN STEAM-BOILERS THE ALLEN BOILER. CARE AND MANAGEMENT OF STEAM-BOILERS. INSTRUCTIONS FOR FIRING DAMPERS STEAM-BOILER INSPECTION Rules for finding the Quantity of Water which Boilers and other Cylindrical Vessels are capa- ble of Containing EFFECTS OF DIFFERENT KINDS OF FUEL ON STEAM- BOILERS BoILER MATERIALS STEEL STRENGTH OF IRON BOILER-PLATE DEFINITIONS AS APPLIED TO BOILERS AND BOILER MATERIALS 64 CONTENTS. PUNCHED AND DRILLED HOLES FOR BOILER SEAMB. Table showing the Strength of Welded Boiler- plates PATENT BOILERS THE GALLOWAY BOILER. _ STRENGTH OF RIVETED SEAMS COMPARATIVE STRENGTH OF SINGLE- AND DOUBLE- RIVETED SEAMS HAND- AND MACHINE-RIVETING COUNTER-SUNK RIVETS RIVETS Table showing Diameter and Pitch of Rivets for different Thicknesses of Plate STRENGTH OF STAYED AND FLAT BOILER SURFACES BOILER-STAYS STAY-BOLTS CALKING TESTING-MACHINES FEED-WATER HEATERS Table showing the Units of Heat required to Con- vert One Pound of Water, at the Temperature of 32° Fah., into Steam at different Pressures GRATE-BARS CHIMNEYS. Table showing the Proper Diameter and Height of Chimney for any kind of Fuel Table showing Heights of Chimneys for producing certain Rates of Combustion per Square Foot of Area of Section of the Chimney SMOKE CONTRIVANCES FOR INCREASING DRAUGHT AND ECONOMIZING FUEL IN BOILER FURNACES 6* 65 CONTENTS. Table showing the Actual Extension of Wrought- iron at various Temperatures Table showing the Linear Dilatatiand of solide by Heat Table deduced from eperrnents on ion lates for Steam-boilers, by the Franklin Institute, Philadelphia Table showing the Results i adnan heaiie on different Brands of Boiler Iron at the Stevens Institute of Technology, Hoboken, N. J. . : Table showing the Weight of Cast-iron Balls from, 3 to 18 Inches in Diameter. Table showing the Weight of Cast-iron Plates pax Superficial Foot as per Thickness Table showing the Weight of Round-iron oat s an Inch to 6 Inches Diameter, One Foot Long. Table showing the Weight of Boiler-plates One Foot Square and from 7,th to an Inch Thick . Table showing the Weight of Square Bar-iron from 4 an Inch to 6 Inches Square, One Foot Long. Table showing the Weight of Cast-iron Pipes, One Foot in Length, from 3 Inch to 14 Inches Thick, and from 8 to 24 Inches Diameter. Table showing the Tensile Strength of various Qualities of American and English Cast-iron . Table showing the Tensile Strength of various Qualities of American Wrought-iron. : 2 Table showing the Tensile Strength of various Qualities of English bas a cea To PoLisH Brass CEMENT FOR MAKING STEAM- “JOINTS STEAM-DAMPERS INDEX 66 EDWARD MEEKS, PHILADELPHIA, Publisher of Roper’s Hand-Book of the Locomotive, including the Modelling, Construction, Running, and Management of Locomotive Engines and Boilers. Fully Illustrated. By STEPHEN Roper, Engineer. Eleventh Edition, Revised, Enlarged and Corrected. 18mo, tuck, gilt edge, $2.50. Roper’s Catechism of High Pressure or Non-Condensing Steam-Engines, including the Modelling, Construction, Running, and Management of Steam-Engines and Boilers. With Illustrations. By StrepHEN Roper, Engineer. Twen- tieth Edition, Revised and Enlarged. 18mo, tuck, gilt edge, $2.00. Roper’s Hand-Book of Land and Marine Engines, includ- ing the Modelling, Construction, Running, and Manage- ment of Land and Marine Engines and Boilers, with the latest improvements in the same. Fully Illustrated. By STEPHEN Roper, Engineer. 600 pages. Tenth Edition, Revised and Enlarged. 16mo, tuck, gilt edge, $3.50. Boper’s Hand-Book of Modern Steam Fire-Engines, in- cluding the Running, Care, and Management of Steam Fire-Engines and Fire-Pumps. With Illustrations. By SrePHEN Roper, Engineer. It is the only book of the kind ever published in this country, as it contains an 67 elaborate description of all Modern Steam Fire-Engines, Boilers, and Fire-Pumps, and is free from formule or ultra mathematical expressions. Fourth Edition. 16mo, tuck, gilt edge, $3.50. Boper’s Engineer’s Handy-Book. Containing a full expla- nation of the Steam-Engine Indicator, and its use and advantages to Engineers and Steam Users; with formule for estimating the power of all classes of Steam-Engines ; also, Facts, Figures, Questions and Tables for Engineers who wish to qualify themselves for the United States Navy, the Revenue Service, the Mercantile Marine, or to take charge of the better class of Stationary Steam-En-. gines. With Illustrations. Fourth Edition, Revised and Enlarged. By StepHen Roper, Engineer. $3.50. Reoper’s Use and Abuse of the Steam-Boiler, including its Care and Management. With Illustrations. This is the only book ever published in this country devoted ex- clusively to Steam-Boilers. It contains illustrations of all the different kinds of Steam-Boilers ‘now in use, whether Stationary, Locomotive, Fire, or Marine; and also of Sectional or Patent Boilers. By STEPHEN RopER, En- gineer. Kighth Edition. 18mo, tuck, gilt edge, $2.00. hoper’s Questions and Answers for Engineers. This little book contains all the Questions that Engineers will be asked when undergoing an examination for the purpose of procaring a license, with the answers to the same, couched in language so plain that any engineer or firemen _can in a short time commit them to memory. Price $3.00. 68 Roper’s Simple Process for Estimating the Horse-Power of Steam-Engines, from Indicator Diagrams, or the work an engine was performing at the time the diagram was taken, One of the most important devices ever employed in con- nection with the Steam-Engine. 50 cents. Roper’s Instructions and Suggestions for Engineers and Firemen. This little book is made up of a series of sug- gestions and instructions, the result of recent experiments and the best modern practice in the care of Steam-Engines and Boilers. It is brimful of just such information as persons of limited education having charge of steam mas chinery need. It is written in plain, practical language, devoid of theories or mathematical formule. $2.00, Roper’s Care and Management of the Steam-Boiler. One of the most practical works ever published on this subject, as itembraces the following subjects: Care and Manage- ment of Steam-Boilers, Horse-Power of Steam-Boilers, Repairing Steam-Boilers, Incrustation in Steam-Boilers, Steam-Boiler Explosions, Testing Steam-Boilers, Exter- nally and Internally Fired Steam-Boilers, Design of Steam- Boilers, Steam-Boiler Materials, Mud-Drums, Steam- Domes, Cleaning Steam-Boilers, Different Types of Steam- Boilers, Feed-Water Heaters, Fuel, Chimneys (area and height), Draught, Smoke, Instructions for Firing, Com- parative Efficiency of Different Types of Steam-Boilers, with a great amount of other information of immense value to owners of Steam-Boilers, Engineers, and Firemen, expressed in plain, practical language. $2.00. 6* i Roper’s Young Engineer’s Own Book, containing an explanation of the Principle and Theories on which the Steam-Engine as a Prime Mover is based; with a description of different kinds of Steam-Engines, Condensing and Non-Condensing, Marine, Stationary, Locomotive, Fire, Traction, and Portable; together with Instructions how to , Design, Proportion, Locate, Repair, Reverse, and Rtun all Classes of Steam-Engines, with Tables and Formulas for finding their Horse-Power; also, Suggestions on the Selections, Care, and Management of all Classes of Steam-Engines, Boilers, Pumps, Injectors, ete., for the Use of Educational Institutions where students are in- tended to engage in Mechanical Pursuits, and for the Private Instruction of Youths who show an Inclination for Steam-Engineering. With 106 illustrations. By SrepHen Roper, Engineer, Author of Roper’s Practical Hand-Books for Engineers and Firemen. Second Revised Edition. 16 mo., tuck, gilt edge, $3.00. 70 Bilgram.—Slide-Valve Gears. A new graphical method for Analyzing the Action of Slide- Valves, moved by eccentrics link-motion, and cut-off gears. By Huco Brueram, M.i 16mo, cloth. $1.00. ; Cooper.—A Treatise on the use of Belting for the Transe mission of Power. With numerous illustrations of ap proved and actual methods of arranging Main Driving and Quarter Twist Belts, and of Belt Fastenings. Exam- ples and Rules in great number for exhibiting and calcu. lating the size and driving power of Belts, Plain, Particu lar, and Practical Directions for the Treatment, Care, and Management of Belts. Descriptions of many varieties of Beltings, together with chapters on the Transmission of Power by Ropes; by Iren and Wood Frictional Gear- ing; on the Strength of Belting Leather; and on the Ex- perimental Investigations of Morin, Briggs, and others. Second Edition. By Jonn H. Cooper, M.E. 1 vol, demy octavo, cloth. $3.50. Grimshaw.—Saws. The History, Development, Action, Classification, and Comparison of Saws of all kinds. With Appendices. Concerning the details of manufacture, setting, swaging, gumming, filing, etc.. Care and use of saws. Tables of gauges. Log measurements. Lists of saw patents and other valuable information. Second Edition, with Supplement. Profusely Illustrated. By RoBpERT GRIMSHAW. Quarto, cloth. $4.00. Overman.—Mechanics for the Millwright, Engineer, Ma. chinist, Civil Engineer, and Architect. By FREDERICK OVERMAN. 12mo, cloth. 150 illustrations. $1.50. 71 Riddell.—The Carpenter and Joiner Modernized. Th>rd Edition, revised and corrected, containing new matter of interest to the Carpenter, Stair-Builder, Carriage-Builder, Cabinet-Maker, Joiner, and Mason; also explaining the utility of the Slide Rule, lucid examples of its accuracy in galculation, showing it to be indispensable to every work man in giving the mensuration of surfaces and solids, the division of lines into equal parts, circumferences of circles, length of rafters and braces, board measure, ete. The whole illustrated with numerous engravings. By ROBERT RIppDELL. 4to, cloth. $7.50. Riddell.—_The New Elements of Hand Railing. Revised Edition, containing forty-one plates, thirteen of which are now for the first time presented, together with the accom- panying letter-press description. The whole giving a complete elucidation of the Art of Stair-Building. By RosertT RippEtt, author of “The Carpenter and Joiner Modernized,” ete. One volume, folio. $7.00. Any of the above works will be sent to any part-of the United States or Canada on receipt of list price. Send money in Registered Letter, P. O. Order, or Postal Note, EDWARD MEEKS, Publisher, No, 1012 Walnut Street, PHILADELPHIA, PA, 72 Soest, em he = he Sk a Se i aR EES Te URBANA VINMI UNIVERSITY OF ILLINOIS pee Sa ON at ke Fp a RRR SAS A Nn ALIA Nt ARE 3 0112 073251008 abi neh Mal lh INE Nt BS ERLE IA Hee Loe