A. PAPER JRELATING TO TRCTI01;E ENGINES AN I) STEAM ROAD ROLLERS, O1t T'I' E PAST, PRESENT ANI) FUTURE OF gTRAM ON TH~ COMMON ROAD, AND Based upon the record of trials of Messrs. Aveling & Porter's Road Locomotives and Rollers, at Orange, N. J., Oct. 1st, 1872. Read before the Polytechnic Club of the American Institulte, November, 1872. BY PROFESSOR R. H. THIURSTON. OF THE Stevens Institute of Technology., Hoboken, N._.: Reprinted from TEIi: Jounx\VL olF Tr}II; lIf,1 slILN INTI'rl'TIr E, Janul;ry, 1873. THE JOURNAL OF THE (Established 185~6.) BEVOTED TO SCIENCGE AND THE E MEHANIC ARTS,'Phis Journal is issued in Mnointilly lurrnbers of' 72 pa1es each, anid regularly containrs origilnal lmatter of ilaterest to( the Engtineering aild Scieentific proftessions, and to thie Mltufact ure r. $tsbci1tittbspon0, P' ice $5.00 _er'3 ant'itvi#ubt.C Business letters should. be addressed to tile Actuarly of' tte Institute; matter for publication, to tile Editor. The Journal can also be obtained froim the following: DAVID G. FRANCIS, New York. JOHN'WILEY & SON, " D. VAN NOSTRAND, " L. W. SCHMAIDT, " W. C. LITTLE & CO., Albany, New York. LITTLE, BROWN & CO., Boston, Massachusetts. A. WILLIAMS & CO., NEW ENGLAND NEWS CO., Boston, Mass. WHITFORD & RICE, Lawrence THE WESTERN NEWS CO., Chicago, Illinois. MOHUN & BESTOR, Washington, District of Columbia. BELL & CO., San Francisco, California. Pcais.-HECTOR BOSSANGE & SON, 11 Quai Voltaire, Nvh Londomw.-EIVES & MACEY, King William Street, are authorized to receive subscriptions and to make exchanges for periodicals devoted to the ArtsH and Sciences. Journal Franklin Institute. Vol. LXV,. Traction Engines or iRoad Locomotives. I "ir4~~~~~~~~~~~~~ ~~~~~ -> fik~~~~~~~~~~~~~~ _________~~~~~~~~~I-r-_:__ I~ ~ ~ ~ ~ ~ ~~~~~~~~~~~~~~~lIIIIii l~~II~zr Ii~IIiii~ 1.tl~l-ll!!'iiiiEiii ll J[l I _ll__!1_{1__11___""'"'__ ) ill'~~~~il,,~~~~~~~~~~~~~~~~~:i t!{lll II!11 I11 tl.zcjIjF- ll~l"llllll~SiI lt~hII1Iflty — __ JillHIIIII OAID LOO OTi by A'velig & Porter. TRACTION ENGINES OR ROAD LOCOMOTIVES.* THE PAST, THE PRESENT AND THE FUTURE OF STEAM ON TILE Co1nIoN ROAD. BY~ PROFESSOR R. IH. TJHURSTON. When, during the last century, the steam engine had so far been perfected that the possibility of its application to other purposes than the elevation of water had become generally recognized, the problemn of its adaptation to the propulsion of carriages was attacked by many engineers and inventors. As early' as 1759, Dr. Robison, who was at the time a graduate of the University of Glasgow, and an applicant for an Assistant Pros fessorship there, and who had made the acquaintance of the instrument maker, James Watts, when visiting the workshop, called the attention of the latter, who was probably then more ignorant of the principles of the steam engine than was the young student, to the possibility of constructing a carriage to be driven by a steam engine, thus, perhaps, setting in operation that train of thoughtful experiment which finally earned for Watt his splendid fame. In 1765, that singular genius, Dr. Erasmus Darwin, whose celebrity was acquirec by speculations in po('ijy and philosophy as well as in medicine, urged Matthew Boulton, -subsequently Watt's partner, and just then corresponding with our cwvn Franklin in relation to the use of steam power,-to construct a steam carriage or "fiery chariot," as he poetically styled it, and of which he sketched a set of plans. A young man, named Edgeworth, became interested in the scheme, and, in 1768, published a paper which had secured for him a gold medal from the Society of Arts. In this paper, he proposed railroads on which the carriages were to be drawn by horses, or by ropes fronm st8eamn-wzindi engines. These were merely promising schemes, however. The first actual experiment was made, as is supposed, by a French army officer, Nicholas Joseph Cugnot, who, in 1769, built a steam carriage which was set at work in presence of the French Minister of War, the Duke de Choiseul. The funds required by him were furnished by the " Read before the Polytechnic Club of the American Institute. Compte de Saxe. Encouraged by the partial success of the first locomotive, Cugnot, in 1770, constructed a second which is still preserved in the G Conservatoire des Arts et Hetiers,' Paris. Watt patented a road engine in 1784, after he had made the more essential improvements in general design and in the details of his pumping engine. At about the same time, Murdoch, his efficient lieutenant,/ completed and made a trial of a model locomotive, driven by a G" grasshopper engine," having a steam cylinder three-quarters of an inch in diameter and two inches stroke of piston. It is reported to have run six to eight miles an hour, its little driving wheels making from two hundred to two hundred and seventy-five revolutions per minute. In 1786, Oliver Evans asked of the Pennsylvania Legislature the monopoly.of his method of applying the steam engine in driving flour mills and to propelling wagons. In the same or following year, Winr Symington constructed a working model of a steam carriage, which may'still be seen in the Patent Museum at South Kensington, London, In 1802, Trevithick and Vivian took out a British patent for a locomotive engine, and their model is also preserved in the Museum of the British Patent Office. In 1804, Oliver Evans completed a flat-bottomed boat to be used at the Philadelphia docks, and, mounting it on wheels, drove it by its own steam engine to the river bank. Launching the craft, he propelled it down the river, using its steam engine to drive its paddlewheelso Evans' " Oruetor Amnphibolis," as he named the odd machine, was the first road locomotive that we find described after Cugnot's time. Evans assured incredulous legislators that carriages propelled by steam would soon be in common use, and offered a wager of three hundred dollars that he could build a " steam wagon" that should excel in speed the swiftest horse that could be matched against it. In 1821, Julius Griffiths of Middlesex, England, made a steam carriage for common roads, which he designed to carry passengers, and which was probably the first ever constructed for that purpose only. During the succeeding ten or fifteen years, IMessrs. Burstall & Hill of London and Edinburgh, Mr. Goldsworthy Gurney, the Messrs. Seaward, W. EH. James, Walter Hancock, Ogle & Summers, Sir Chas. Dance, and others in. Great Britain, and Harrison Dyer, Joseph Dixon, Rufus Porter and a Mr. James, in the United States, with, probably, many others whose names are unknown in history, attacked this important and seductive problem with varying success. In December, 1833, about twenty steam carriages and traction road engines were running, or were in course of construction in and near London. In our own country, the roughness of roads discouraged inventors, and, in Great Britain even, the successful introduction of road locomotives, which seemed at one time almost an accomplished fact, finally met with so many obstacles that even Hancock, the most ingenious, persistent and successful constructor, gave up in despair. Hostile legislation procured by opposing interests and, possibly also, the rapid progress of steam locomotion on railroads caused this result. In consequence of this interruption of experiment, almost nothing was done during the succeeding quarter of a century, and it is only within a few years that anything like a business success has been founded upon the construction of road locomotives, although the scheme seems to have been at no time entirely given up. J. Scott Russell, Boydell, and a few others in England, and Messrs. Roper, Dudgeon, Fawkes, Latta, and J. K. Fisher, in the United States, have all, at various times labored in this direction. The last-named engineer designed his first steam carriage in 1840, and is still at work. Abroad, a few firms have succeeded, within a few years past, in making a business of considerable extent in constructing road locomotives for hauling heavy loads, and in building steam road rollers. While steam carriages of high speed, and adapted to the transportation of passengers, have not yet been successfully introduced, a most promising start has been made in the application of steam to the heaver kinds of work on the common road. The great impediments seem to be the roughness and bad construction of the ordinary highway, the damages arising from the taking fright of horses, the engineering difficulties of construction and the limited power of the machine as it has usually been built. Hostile legislation might perhaps be placed in the category, but we are probably sufficiently far advanced in civilization to-day to be able to secure liberal legislation when the people shall be satisfied that the introduction of the road locomotive will be of great public advantage. The capabilities of the road locomotive are readily determined by experiment, and the following paper embodies the results of several series of trials. When in Great Britain, some two years ago, the writer found that 4 the construction of traction engines and steam road rollers was occupying the attention, to a considerable degree, of several engineering firms, among whom may be mentioned Messrs. Aveling & Porter, Tuxford & Sons, Burrell, Ransomes Sims & Head and others.Messrs. Fowler & Co. were constructing machines to be used in steam ploughing, an application of steam to which they were giving especial attention. The first-named firm seemed a leading one in the business of building road locomotives, and about 400 workmen were kept employed by them. Their engines seemed well built and had an excellent reputation, but, unfortunately, the short time available merely permitted an inspection of their machines, and no opportunity offered to witness a prearranged trial, or even to see them at ordinary work. More than two years previous to the period just referred to, a trial of these machines was made by the well known French engineer, Mon. H. Tresca. Sous-directeur du Conservatoire Imperial des Arts et Metiers, Paris, and in presence of the equally distinguished English Professor, Fleemin Jenkin. The report was submitted to the Dzreeteur, General Morin, January 15th, 1868.* The results may be summarized as follows: 1. The coefficient of traction was determined to be about 0'25 on a good road with easy grades. 2. The consumption of coal was found to be 4'4 pounds per horsepower per hour. 3. The consumption of water was determined to be 132'2 gallons an hour with the "'ten-horse "' engine. 4. The "coefficient of adherence," or of friction between the wheels and the soil was 0'3. 5. A rate of motion of seven miles an hour produced no special difficulty in managing either the locomotive or its load. This engine was of large size, having a steam cylinder of 11 inches diameter and a stroke of piston 14 inches. The crank shaft was geared to the driving-wheels in such manner as to make 20'33 or 14'25 revolutions, at pleasure, for each revolution of the drivers. The driving-w-heels were 61 feet in diameter, and the weight of the machine, exclusive of fuel and water in its tank, was fourteen and one-half tons. Including fuel and water its weight was seventeen *Proces-verbal des Experiences faites sur une machine de traction; Conservao. toire des Arts et Metiers; Paris; 1868. 5 and one-half tons. The load drawn on a level road was 79 tons, 19 *cwt., 1 qr., (77,597 kilo's), including the weight of the machine itself. This weight was distributed as follows: Weight of engine, 2118 per centum of total. " wagons,. 259 " "' paying load,. 52'3 " 100' In addenda to the report of M. Tresca it is stated that M. Lalouette had set the engine at work transporting heavy material, and with the following results: It transported a total weight of 2,500,000 kilogrammes a distance of 4 kilometres, drawing, on each trip, 25,000 kilogrammes of paying load, and making four trips per day. Five hundred kilogrammes of coal were consumed in eight journeys. At about this same time, M. Servel, lngenieur en chef de la Compagnie Generale des Messageries t VaTpeur, conducted a series of experiments with a similar machine upon paved and upon macadamized roads, during what he describes as the most trying of winter weather. Under such unfavorable conditions, M. Servel reports the following distribution of weights by per centurn: Weight of locomotives,... 41.4 " wagons,... 18'2 c' paying load,... 40'4.100. The average total weight of three loaded wagons, which was the usual load, was 22,575 kilogrammes, or very nearly 22 tons. The experiment was made in 1867 —'8 of applying these engines to the towage of boats on the French canals. The results seem to have been very encouraging. M. Geraldi reported that an 8-horse engine towed on the canal between Caen and Oyestreham, a fleet, having an aggregate measure of 800 tons, at the rate of three miles an hour, and that the speed had been pushed, on occasion, up to six miles an hour. The latter speed was not considered an advisable one, however. M. Carfort reported to M. Huet that a 6-horse engine, doing similar work on the Dunkerque and Saint Omer canal, had towed 800 tons and was regularly towing 500 to 700 tons at an expense not exceeding 40 per centum of the cost of horse power. In the year 1871 a number of traction engines were exhibited before the Royal Agricultural Society of England at their show at Wolverhampton, and the judges appointed by the Society made a series of exceedingly interesting and instructive tests.* The judges state in their report that on a road in good order wheels fitted with India-rubber tires, as patented by Thompson, have an advantage over iron rigid wheels in tractive force, but that the cost of such wheels-fifty per centum of the cost of the locomotive-forms a most serious obstacle to their adoption; still they " are not prepared to express a decided opinion" upon that subject. On farm roads and in fields the India-rubber tires "signally failed." Plain iron wheels, with "paddles" attached, succeeded where the former failed. A 10-horse locomotive entered by Messrs. Aveling & Porter received the first prize at the termination of these trials; two competing systems of rubber tires-those of Thompson and of Adams-were each awarded a silver medal; a 6-horse power road locomotive by Aveling & Porter, and an 8-horse power road engine by Burrell, were very highly commended. The prize engine had a cylinder of 10 inches diameter and a stroke of piston of 12 inches, a fire grate area of 61 square feet, an area of heating surface of 204'4 feet, driving-wheels 6 feet in diameter, and 18 inches breadth of face. These wheels made one revolution to 17 of the crank shaft. The total weight of the engine was 12 tons, of which 843 were on the driving-wheels. The coal used, on special trial, amounted to 3'2 pounds per indicated horse power per hour, and the evaporation of water was 7'62 pounds per pound of coal consumed, the average temperature of feed being 175Q Fahrenheit. The load drawn up the maximum grade of 264 feet to the mile on Tettenham hill, which is 1900 feet from top to bottom, was 26 tons, or, including weight of engine, 38 tons, giving a coefficient of traction of 0'35. On a country road, 16 miles long, it drew 15 tons at an average rate-ifsspeed of 31 miles per hour, using 2'85 pounds of coal and 1'94 gtiius of water per ton of useful load per mile. On farm soil, soaked with recent rains, the load drawn was 9 tons, -and speed'som ething less than an average of two miles per hour, using 13.6 pounds of coal per ton of paying load per mile. This engline was fitted with smooth-tired driving-wheels. Jonurnal of the Royal Agricuitural Society of England, Vol. VII; London J. Murray, 1871. In July, 1871, another trial was made in the same vicinity at the request of officials of the British War Department, during which a 6-horse engine, by the same builders, drew 7 tons, 12 cwt., up a hill having a maximum grade of one in 7'33, or more than 600 feet to the mile. In September of the same year still another trial of the same, or a duplicate engine, occurred between Rochester and Chatham, in which the same style of driving-wheel was used as in the trials at South Orange, N. J., to be hereafter described. Star Hill was ascended by this engine, the maximum grade being 480 feet to the mile. This performance is compared by Engineering with that of a road steamer fitted with India-rubber tires, which was tried earlier at Tettenham. The first named engine drew 2'94 times its'own weight, and its competitor hauled 2'5 times its weight on maximum grades of I in 11 and I in 18, respectively-excellent performances both. The rigid wheel in this case seems to have had considerably greater pulling power than that fitted with elastic tires. The authorities already quoted furnish valuable information as to the capabilities of this system, but the writer, in common with many others of the profession, has long been desirous of learning more of its value on good roads by personal observation. Fully believing in the ultimate and general adoption of steam traction on our streets and roads, it yet seemed a question whether there might not exist some unanticipated -obstruction, or some serious difficulty not referred to in published reports. The desired opportunity recently presented itself when the writer was requested to conduct a public trial of the road locomotives of Messrs. Aveling & Porter, and of their steam road rollers, and was proffered every desired facility for making a thorough examination of the construction of the machines, and for testing their powers of traction and manoeuvring. Mr. WT. C. Oastler, agent for the builders, promised to furnish one locomotive, and Mr. Daniel Brennan, Jr., President of the Telford Pavement Co., of Orange, N. J., offered a road locomotive and a steam roller, with the privilege of taking as a trial ground any portion of the macadamized road which the company were constructing at South Orange. Engagements permitting, a day, Saturday, September 21st, was taken for a visit to Orange to inspect the engines and to select a trial ground. The trial was to ta.ke place October 1st, and invitations were * London Engineering, July 14, 1871. extended to and accepted by the Commissioners of Public Roads for Essex and for other CoVnties of New Jersey, and by many well-known engineers of New York and vicinity. Two road steamers or traction engines and a steam road roller were ought out for exhibition and trial. No. 1 was a new road locomotive built by Messrs. Aveling & Porter it had previously done no real work. A sketch of this machine is shown in Figure 1. The following are the principal dimensions: Weight of engine, complete, 5 tons, 4 cwt.,. 11648 lbs. Steam cylinder —diameter in inches, 7.. Stroke of piston-inches,... 10. Revolution of crank to one of driving-wheels, 17. Driving-wheels-diameter in inches,.. 60. "' — breadth of tire in inches, 10. -weight, pounds each,. 450. Boiler-length over all, feet,.. 8. " — diameter of shell, inches,.. 30. " -thickness of shell, inches,. - "' — firebox sheets, outside, thickness in inches, ~. Load on driving-wheels, 4 tons, 10 cwt., pounds, 10,080. The boiler was of the ordinary locomotive type, and the engine was mounted upon it, as is usual with portable engines. The driving pinion on the crank shaft was made capable of being slipped out of gear, thus allowing the engine to be kept in motion when the locomotive was at rest, either to pump water into the boiler or to drive as a " portable engine," by a belt which could be carried on the pulley, 4~ feet in diameter and 5 inches face, which was fitted to act as a fly-wheel. When used as a "portable engine," regulation was effected by means of a fly ball governor conveniently attached. The steam cylinder was steam jacketted in accordance with the most advanced practice here and abroad. The crank shaft and other wrought iron parts subjected to heavy strains were made of Lowmoor iron and were strong and plainly finished. The gearing was of malleableized cast iron, and all bearings, from crank-shaft to drivingwheel, on each side, were carried by a single sheet of half-inch plate, which also formed the sides of ithe fire-box exterior. This simple but admirable device united all parts, peculiarly exposed to injury by jarring, with such firmness as would seem to give almost absolute, security against such injury on even very rough roads. See Fig. 1. 9 The engine valve gear consisted of the standard arrangement of three ported valve and Stephenson link with reversing lever, so generallyvused on locomotives. The feed pump, 13 inches in diameter and 3~ inches stroke of plunger, was driven by an eccentric keyed on the crank-shaft. The connection between the gearing and the driving-wheels was effected by one of the neatest and most ingenious devices known to engineers. This arrangement is called by builders of cotton machinery a " Jack-in-the-box" gear, and is shown in Fig. 2 as the "differential gear:. Fig. 2. A>!{11it OIFFER ENTIAL GEAR As constructed, and as shown in the figure, one wheel (A) turns freely on the driving-axle at B, while the other driving wheel is keyed fast. The latter is not shown in the cut. A bevel gear (C) is bolted on the hub of the wheel (A), and a similar gear (D) is keyed to the driving-axle. Between these revolves a spur gear (E), which is driven by the engine, and which carries two small bevel pinions (FF), the latter engaging both bevel wheels, C and D, their axles being in the plane of revolution of the large gear (E). An examination of the combination will show that, resistances being equal on both wheels, if the spur gear (E) be turned, it will carry with it both driving-wheels at the same time with equal angular velocities, the effort exerted by the engine being equal at both wheels at allitimes. If the engine be turning a corner, however, the greater resistance 10 on the inside wheel retards that, while the outer wheel necessarily moves more rapidly over its longer path, and, while the engine still exerts the same force on both wheels, the work done is distributed unequally between them through the then revolving bevel pinions, without lss and without either wheel being necessarily slipped or disengaged. Should one wheel, however, strike into a soft spot, as a patch of muddy soil, and finding so little resistance as to turn freely, leaving the opposite wheel at rest on firmer soil and thus checking the motion of the locomotive, a heavy bolt, which is furnished with each machine ready fitted to its place, is inserted and keys the loose wheel to the shaft. Both wheels must then turn together until, the locomotive being extricated, the bolt is withdrawn. Such an occurrence is seldom likely to take =______ g__ place. The driving-wheels were of wrought iron, strong but light in their construction, and were fitted with strips of iron, thickest at the middle of their lengths, which were laid diagonallyacross the face of the wheels, with separating spaces of about two inches between them. The angle was such that one end of one strip would come to a bearing on the ground just as the opposite end of the preceding strip was leaving it. This arrangement is shown in Fig. 3. The builders claim that this method of obtaining tractive power in the wheel gives the engine a pulling power, on good ground, equal to 0.45 of the insistent weight,* while, with the smooth wheel used in the trial described in the report to the Royal Agricultural Society, quoted above, that coefficient is but 0'25. On extremely hard and smooth roads, bolts may be inserted in the wheel rim, whose heads give better holding power than even these * This is equal to that obtained with the India-rubber tired wheel at Wolverhampton. A committee of the Royal (British) Engineers, consisting of Colonels Gallway, Wray and Lennox and Captain Home, compared the pulling power of these wheels with that of India-rubber tired wheels in November, 1870, using the same engine with both, on Star Hill, near Rochester. They found them to be equal, with equal insistent weights. The writer regrets that he has no personal experience with which to compare these results. iron strips, and on very soft ground the same bolts are used to secure to the rim of the wheel pieces of angle iron, called by the builders " paddles," which take a good hold upon on the more unstable kinds of soil. The weight of this locomotive rested principally upon the drivingwheels; about fifteen per centum was left upon the forward axle to insure good steering power. The total weight on the drivers was somewhat increased when pulling a load, usually, by the inclination of the line of traction downward from the pulling bolt to the point of attachment to the load. The forward axle is fitted with wheels of 42 inches diameter and 8 inches face; it swings about a king-bolt which is secured above in a bracket secured to the under side of the boiler smoke-box and is steadied by a strong rod, connecting its lower end with the forward end of the fire-box. Chains led from each end of the axle to a shaft carried on the forward end of the fire-box, around'which they wound in such a manner that turning this shaft would swing the axle. A hand steering wheel, conveniently arranged near the-throttle and reversing handles, turned this shaft, being connected with it by means of a worm shaft and pinion. A tank at the rear of the locomotive carried coal and wat,er in its compartments, and afforded a standing place for the engine driver from which he could readily reach the various handles and guages. Draught was secured by means of the exhaust, and, when desired, the latter could be turned into the water tank, thereby securing a double advantage, heating the feed water'and rendering the engine noiseless. The boiler and steam cylinder were both well protected against losses of heat by coverings of felt and lagging. No springs were used on the engines exhibited as, being intended for heavy work at slow velocities, their advantages would not, it was supposed by the builders, justify the expense and complication attending their use. A strap brake was fitted on the driving axle for the purpose of controlling the engine on heavy grades. Road locomotive No. 2 was of the same size and of similar make to No. 1. It had been two years in use, or longer, on the roads made by the Telford Pavement Company, as a steam road-roller. To convert it into a road-roller, its ordinary driving-wheels had 12 been removed, and, in their place, were fitted a pair of cast-iron wheels, of similar diameter, but of 20 inches breadth of face, and weighing 8,800 pounds each. Their faces were left smooth, as hauling power was not desired, and as it was intended that they should leave the surface of the road as smooth and as firmly compacted as possible. In these driving-wheels, the engine carried an excess of weight of 6,700 pounds as compared with No. 1. In statements of work done, this excess should be entered as a part of the paying load where N o. 2 is employed as a traction engine. The great weight of these wheels has an important effect in preventing the liability of slipping, which is a consequence of their smooth surface, and should bring up the equivalent coefficient of adherence, in terms of the original weight of the engine, to about 0'42, or nearly equal to that of No. 1 with its regular traction wheels. As, during the trials about to be described, no slip was in any case -observable, this difference would not in any way affect the results. The weight of the steam road-roller offered for trial, everything included, was fifteen tons, or 33,600 pounds. This machine is represented in Fig. 4. Ali.......=..=..._._ ----------------------- — ~~~~~~ti 13 The engine and boiler were of the same general dimensions as the road locomotives already described. The furnace door was placed at one side of the fire-box, and the reversing lever, throttle handle and steam gauge were all brought to the same side, the engine driver standing on the frame of the machine, which is sufficiently broad and is immensely strong. The tanks for fuel and water were so placed as to be within reach of the driver. The steering apparatus was located at the side opposite the working gear of the engine, and was operated by the engine driver's assistant, who finds standing room on that side. The whole machine was carried on four large wheels, with broad tread, covering a total width of six feet. Its weight exerts a compressive force of 5,600 pounds on each foot of width, or 467 pounds on each inch. The wheels had holes drilled in their faces, like the wheels of the traction engines, in which could be inserted strong spikes for breaking up old roads previous to making repairs, or for loosening the surface previous to metalling new roads. Referring to Fig. 4, it will be noticed that the steering wheels are set close together, at the fire-box end of the machine, on an axle, the outer extremities of which are secured in boxes carried by a turntable. This, being turned by the steering apparatus, carries the wheels in either direction, as desired. The driving wheels, in this design, are driven from a counter shaft by a strong fiat link chain, leading around a chain wheel on that shaft, and driving a similar but larger wheel on the driving axle. The chain links are made of forged scrap, case hardened, and the pins were of steel. A brake on the driving axle was of sufficient power to control the roller on the heaviest grades. The whole machine was evidently well proportioned, and of great strength and simplicity in details. PRELIMINAXRIES.-The preliminary examination of the proposed trial ground and its selection took place late in September, and a half day was devoted to an examination of the engines and of the road-bed. Engine No. 1 was found at Orange, and, after a careful examination had been made of its design and construction, the driver started with it over an awkwardly narrow and winding piece of road, traversing it without apparent difficulty, and going forward and backward at varying speeds, steering with evident ease and accuracy. The writer then took the place of the driver, and, although the experience was a novel one, found no difficulty in acquiring, in a very 14 short time, such command of the machine that it became evident that but little training would be required fo enable any ordinarily intelligent mechanic to manoeuvre the locomotive on the most difficult road. The reversing handle, the throttle and the steering wheel were conveniently located and easily operated. Reversing could be performed promptly, notwithstanding the weight and consequent momentum of the fly-wheel, which, it had been apprehended, might cause loss of time, if not an excessive strain, when reversing suddenly. -Steerage seemed almost equally easy and precise, whether going forward or backward. A block of wood, six or eight inches high, thrown under one forward wheel, was driven over without apparent difficulty or injury to the machine. After these experiments and the examination of the locomotive were concluded, the party rode over to South Orange, where a portion of road containing heavy grades was selected for the public trial of the locomotives which have been described. It consisted of a short section of nearly level road, A A' (Fig. 5), in the village of South Orange, near the railroad station, and of that part of the road, on either side of this nearly level stretch, which ascends from the valley by a moderately heavy grade, A E, on the eastern side, and by a very remarkably steep grade, A'W, on the western side. The profile, as given, was kindly furnished by the county engineer, Mr. Jas. Owen, of Newark, N. J. This forms a portion of some fourteen miles of macadamized road, completed, during the past season, by the Telford Pavement Co., to whom No. 2 locomotive and the steam roller belonged. The road-bed was remarkably smooth, hard and compact. It was constructed in the following manner: The original surface of the old road was first ploughed up and levelled off, the ploughing being done by an immense plough, built for that purpose, and designed to be drawn by the road locomotive owned by the Pavement Company. The surface is next carefully levelled up and brought to the required form, and is well rolled by the steam road-roller. The bed is then ready for the metalling. This consists of fragments of the very hard trap rock which lines the western bank of the Hudson river, near New York, and forms the Palisades, extending back from the river into the State of New Jersey. The quarry is situated a short distance from the South Orange Railroad station, the county road leading directly past it. Steam drills are employed in holing, and the masses broken down by the blast are reduced by the quarrymen to a size which allows them to enter between the jaws of two Blake stone crushers, which are kept constantly at work preparing broken stone for the road. The whole plant is well placed and well arranged, and exhibits many interesting features which cannot be described here. The heavier fragments are separated, by means of revolving screens, from the finer pieces and are used in forming the first layer of metalling. These heavy fragments, measuring from four to eight inches in their longest dimensions, are placed by hand, and the workmen settle them well in their place by striking them with a moderately heavy hammer. Another layer of smaller material is used to cover that first laid down, and, upon this the steam road-roller is used until'it is well compacted. As still finer material is added, the rolling is repeated until the surface becomes wonderfully hard and smooth. -As a matter of course it must be extremely durable, even under heavy traffic. The trap rock used as metalling is one of the finest kinds of material to be found in our own or any other country, aid the method of working it, here adopted, seems to be well adapted to'securing the best results with it. Such remarkably fine roads are, -unfortunately, too seldom seen in this country, although not unfrequently met with in Great Britain and on the Continent of Europe. The fact is due partly, no doubt, to the infrequency of occurrence of such excellent material for metalling, but principally arises from the circumstance that very few boards of road commissioners are sufficiently interested in their work, and, at the same time, sufficiently energetic and far-sighted to indulge in what often seems extravagant expenditure, but what is really one of the most important among the means available for economizing greatly the cost of local and suburban transportation. 16 The road selected for the trials had been just made in the manner above described and seemed in excellent order, although the president of the company considered that it required considerably more rolling to make it what it was intended to be and in accordance with his specifications. The trials were planned, and September 27th was the date fixed for them. That day proving stormy, they finally took place October 1st, in presence of a large number of gentlemen interested, professionally or otherwise, in the subject. The log was kept by student J. A. Henderson, of the class of 1873, Stevens Institute of Technology, to whose intelligence and zealous interest the writer is greatly indebted for the completeness of the record, as well as its accuracy. FIRST TRIAL.-The first trial was made at 10 o'clock, A. M., Oct., 1st, with Engine No. 1. The load consisted of two wagons heavily laden with stone, and weighing, with their loads, 5000 and 5600 pounds, respectively —a total of 10600 pounds. This load was drawn up a grade of 10'10 in 100-B. B. Fig. 5equal to 533'28 feet per mile. The wagon tires were very narrow and much worn, and were observed to cut into the roads somewhat, notwithstanding the thoroughness with which the road-roller had done its work. The driver of the engine was a lad without experience. By putting coal in large pieces on his fire, at the worst portion of his route, he caused his steam pressure to fall rapidly, and was compelled to stop on the heavy grade until the pressure rose to 90 pounds again, when another start was made, and the top of the hill was reached without apparent difficulty. Some annoyance was experienced from priming, partly in consequence of the low pressure maintained in the boiler, but principally, no doubt, because the boiler had not been in use long enough to thoroughly clean its interior surfaces. This engine was, therefore, detached, and No. 2, which had been long in use, was taken for the next. trial over this. same course. SECOND TRIAL.-A trial was next made of the power of manoeuvering possessed by these engines. No. 1 was stationed at a part of the road which had not been rebuilt, and where the ground was soft and uneven.. The machine turned continuously for a considerably time, in a circle of 18 feet radius, crossing the gutter at one part of the course, and gave no v(dence, of difficulty arising from any cause. The engine could turn, when required, in a space slightly greater than its own length by carefully backing and filling. THIRD TRIAL. —Locomotive No. 2, being attached to the same two wagons used in the first place, drew them up the hill to the summit without halting, and without priming or difficulty of any kind. The steam gauge indicated, at starting, 120 pounds, and at stopping, 90 pounds pressure of steam. The time occupied in traversing 1450 feet was 31 minutes; the speed being about 4- miles per hour. Returning to the foot of the hill, a third wagon was brought up and attached, with the other two, to the same locomotive. FOURTH TRIAL.-The total load in wagons was now 16530 pounds, and the excess in weight of the rolling wheels of this engine over the regular and, as already stated, more efficient traction driving wheels of No. 1, brought up the figure to a total of 23230 pounds. This load was taken up the same heavy grade in four minutes,almost precisely four miles an hour. The steam pressure varied from 105 to 120 pounds. The action of the driving wheels was carefully observed, but no evidence of slip could be discovered, with even this last heavy load. The proprietor and agent both desired to try again, using the same engine, with a fourth wagon added to the train, but time was passing rapidly'and it was decided to change the ground, and to experiment with heavier loads on less exceptional grades. FIFTH TRIAL.-The locomotives and wagons were taken across the railroad track to the other portion of the selected road —A, E, Fig. 5-where the grade was 4'27 feet rise in 100 of horizontal distance, or 225'46 feet per mile. This did not approach, in steepness, that already described, but it was, nevertheless, a heavy grade. Engine No. 1 was here attached to a train of six loaded wagons,, weighing, all together, 31080 pounds. Starting with 95 pounds of steam, it drew the train steadily, and with apparent ease, except when, as in the first trial, priming occasionally produced some annoyance. SIXTH TRIAL. —The train was stopped, engine No. 2 was substituted for No. 1, and, with the same load, on the same grade, a trial of speed was made. The mean speed, over the whole course, was 3'6 miles per hour, that figure being somewhat exceeded at times. The steam pressure varied between 90 and 105 pounds. The length of the course was 1435 feet. SEVENTH AND LAST TRIAL.-A train of ten wagons was, next made up, and engine No. 2 was attached. The total load was now 63400 pounds; the course was the same as during the preceding trial. Several unsuccessful attempts were made to start this load, the connecting chains snapping as soon as the strain came fully upon them. Chains were finally obtained of sufficient strength, and a start was made. The load, increased by the weight of a large number of men and boys who clustered upon the wagons, was taken to the top of the hill without accident and without a halt. The steam pressure varied between 85 and 124 pounds per square inch. At the lower pressure, the throttle was carried full open, and it was evident that all the steam that the engine would take was required to keep the piston moving. At starting, the engine exhibited a tendency to rise forward. It may be concluded from these two facts that' this load was about a maximum for the engine when carrying 85 pounds of steam, and that, while drawing it, nearly all the weight of the engine was brought upon the drivers. Even during this trial no slip of the driving-wheels could be detected, notwithstanding the fact, already stated, that they were smooth on their wearing surfaces. The marks left, by the bolt holes in their rims, upon the surface of the road were perfectly distinct and undistorted. The engine gave no trouble by priming. It was noted, during the trials on this grade, that the wagons would just start backward down the hill when detached, 1,nd it is therefore to be concluded that the coefficient of traction on a level, corresponding with the co6fficient of rolling resistance, must have been very nearly represented by the tangent of the angle of the grade, or about 0'0427; it may be assumed at 0'04. Coal.-The amount of coal used on this engine during the day was 350 pounds. Effect on the BRoad-bed. —During all trials, the effect produced by the locomotive upon the road surface was carefully observed and compared with that produced by the hoofs of the horses, which were at intervals climbing the second grade with loaded wagons similar to those used with the traction engine. The hoofs of the horses, it was noticed, cut into the road somewhat, loosening the metalling and injuring the surface, thus increasing the resistance offered to the vehicles following them. The wheels of the traction engine, on the con 19 trary, very perceptibly compacted and improved the road, and thus, to some extent, reduced tractional resistances. There was a marked difference in the action of the two motors upon the surface, and it was evidently a matter of economical importance. Ilorses vs. Steam.-Each wagon could usually be drawn to the top of the hill by two good horses, but only with very great effort. Three were required to do the work as comfortably as it should be done, and this number could pull a single load steadily and with moderate exertion. The locomotive on this grade therefore performed the work of between twenty and thirty horses. We may conclude that it can, with 85 pounds of steam, draw a load which would require the severest exertion of twenty horses. The maximum steam pressure proposed by the builders of these engines is 130 pounds, at which pressure they are still far below the limit allowed by our own laws. It was now late in the afternoon, and it was concluded to suspend work for lack of time to make up other trains. The great steam road-roller was brought forward; its construction was examined by all present, and its effective action in compacting the road was observed. It moved backward and forward, on this grade of 225 feet to the mile, rapidly and steadily, and was said by its owner to be able to ascend the grade of 533 feet to the mile, upon which the first trial was made with the traction engine. The day's work thus terminated and the party separated. The information which had been acquired respecting steam traction and the construction of metalled roads was most valuable, and it was considered by all that the day had been spent pleasantly and profitably. Resume. Reviewing the experiments on the Aveling & Porter road locomotives and steam road-roller, we may make a brief resume of the facts developed, thus: 1. A traction engine may be so constructed as to be capable of being easily and rapidly manoeuvred on the common road and in the midst of any ordinary obstructions. 2. Such an engine may be placed in the hands of the average mechanic, or even of an intelligent youth of 16*, with confidence that he will quickly acquire, under instruction, the requisite knowledge and skill in its preservation and management. * The manufacturers state that one of their most skillful drivers, at Wolverhampton, was a boy of 14. 20 3. An engine weighing rather more than five tons may be turned continuously in a circle of eighteen feet radius without difficulty and without slipping either driving wheel, even on rough ground, and may be turned in a roadway of a width but slightly greater than the length of the locomotive, by proper manoeuvering. 4. A road locomotive, weighing a tons, 4 cwt., has been constructed, which is capable of drawing, on a good road, more than 23,000 pounds up the almost unexampled grade of 533 feet to the mile at the rate of four miles an hour. 5. Such a locomotive may be made, under similar conditions, to draw a load of more than 63,000 pounds'up a hill rising 225 feet to the mile, at the rate of' two miles per hour, doing the work of more than twenty horses. 6. The action of the traction engine upon the road is beneficial, even when exerting its maximum power, while, with horses, the injury to the road-bed is very noticeable. 7. The coitfficient of traction is, with such heavily laden and roughly made wagons as were used at South Orange, and under the circumstances noted, not far from four per centumn on a well made macadamized road. 8. The amount of fuel, of good quality, used may be reckoned at less than 500 pounds per day, where the engine is a considerable portion of the time heavily loaded, and, during the remaining time, running light. It may be considered, without probability of serious error, that, during the trials at South Orange, Engine No. 2 performed pretty nearly an average day's work. DEDUCTIOJONS.-A number of interesting problems may be solved by reference to the facts learned here. A comparison of the efficiency of the road steam traction engine with that of horse-power, in drawing heavy loads, is especially important, and we will now make such a comparison, basing it upon the most reliable data at hand. Traction Force. —It has been already stated that Engine No. 2 developed a tractive force equal to that of twenty horses. The actual tractive force may be determined as follows:-The coefficient of traction was, as has been- shown, not far from 0'0427, which is also very nearly the maximum figure given by General Morin, as determined by his experiments with "dray-carts" and " chariot-porte-corps d'artillerie," upon metalled roads and upon roads paved with sandstone.* This coefficient is large, partly in conse* Morin's Mechanics: New York, D. Appleton & Co. 1860, p. 348. 21 quence of the very slight breadth of the wheel tires and the small diameter of the wheels of the wagons used, and partly because the wagon bodies were not mounted on springs. To be absolutely certain that no error is committed by over-estimation in the following calculation, this coefficient will be taken at 0.03. The actual tractive force required to overcome the rolling resistance was, then, 63,400 x 0'03 = 1902 lbs. The force required to overcome that component of the force of gravity which directly resisted the motion of the load, in this case, where the road laid at an angle with the horizontal, whose tangent was 0'0427, was W Sin 0 2,700 pounds; the total resistance was therefore 4,602 pounds. Including the weight of the traction engine itself, these figures become 2,251 and 3'002 pounds, giving a total of 5,253 pounds direct resistance, and a co-fficient of adherence of 5,253 -- 18,348 - 0'28, which slightly exceeds that found on earlier trials of smooth wheels. Experiments made by Capt. Robt. Merry, at the Jackson Iron Mine, Negaunee, Mich., and the observations and experiments of the writer, indicate the maximum'direct tractive force of a good horse to be about 250 pounds. This corroborates the estimate already made, making the tractive power of this engine equal to that of twenty horses. Deducing from the above the weight which could be drawn, on an equally excellent but level road, by this locomotive, the coefficient of traction being the same, we find it equal to,253 _ 5,100 pounds, or very nearly eighty gross tons, and excluding the weight of the locomotive (163,452), seventy-five tons. With the machine, as with the animal, it would not be expected that, in regular work, on ordinary roads, more than one-half of the maximum power would be exacted,* although, with such a reserve, the machine possesses a decided advantage over the'animal. Working'Tine.-The working time of a horse is usually considered to be eight hours per day for dray horses, and less for carriage horses. The dray horse which is kept in harness eight hours per day, is usually standing unworked a considerable proportion of this time while his load is handled, and also during one-half, usually, of the remaining time, his vehicle is drawn unloaded. The horses of the Third Avenue street railroad, in New York City, are worked less than six hours per day, and are given one day in seven as a day of *Vide, Steam Engines and Prime Movers: Rankine, chap.- 3, p. 85. 22 rest. This is about equal to the working time of horses and cattle crossing our Western plains with moderate loads. The steam engine: requires no such careful limitation of working time. It can work twenty-four hours uninterruptedly as readily as a single hour. Ten hours a day would be, in most cases,'made the daily working time of a road locomotive, the period being determined by the proper length of the working day of the driver, rather than by the capabilities of the machine. The working time of the traction engine may therefcre be stated to be, orldinarily, twenty per centum greater thtan that of the dray horse, and to be capable of indefinite extension when required., The loss of working time by the horse through illness, at the farriery, &c., and that lost by the locomotive in the repair shop, are proper subjects for comparison, but it is difficult to determine them in the absence of reliable data. We may estimate these losses as equally affecting the two motors, with a probability that the correction of any error in such estimate may make a change favorable to the locomotive. First Cost.-Comparing the first cost and running expenses of steam and of horse power, we may work from tolerably well established data. The list price of the Aveling & Porter road locomotive, experimented with at South Orange, is, delivered in New York, about $4,000. The average cost of horses purchased by the Third Avenue Railroad in New York city, is now $157.50, and it would require more than twenty such horses to pull the load of the traction engine, while an addition of twenty-five per cent. must be made for the greater length of the working day of the locomotive. Twenty-five such horses would have a first cost of $3,937.50, to which must be added -the large item of cost of harness. The first cost of steam and of horse power is, therefore, nearly equal, the differencee being in favor of steam, leaving, also, on the side of the engine, the immense advantage arising from its ability to work longer hours when required, and indefinitely. The interests on these first costs also nearly balance each other. Running Expenses.-The running expenses of the locomotive consist of cost of attendance, of fuel, oil and repairs and of depreciation in value with use; those of horse power are attendance, food, stabling, sickness and depreciation with age. The- cost of attendance upon the one engine and the twenty-five horses may be taken at $939 and $3,130, respectively, assuming each 23 driver of the latter to be able to manage a six-horse team. The engine driver receives three dollars per day and the other men two: dollars and a half, and there are are 313 working days in the year. The cost of fuel, oil, and incidentals, excluding repairs of the engine and its depreciation, may be averaged at $900 per -year, in the vicinity of New York.'This is somewhat higher than the cost of similar items on railroad locomotives in New York State.* The cost of repairs and depreciation has been thus far so small at South Orange that it could not be estimated, but for the life of the engine, it will be likely to average something less than fifteen per cent. of the first cost, or, in this case, $600 per annum. This we arrive at by an examination of railroad locomotive expenses,t as officially reported. The total annual expense, therefore, of the traction engine referred to may be reckoned at $2,439 as a maximum figure, including cost of attendance. A similar estimate will give, for the annual expense of keeping one horse, very exactly $300, excluding attendance. In the year 1870, 10,315 horses in the State of New York cost for stabling, feeding, repairs to harness and shoes, &c., according to the official statements, $3,182,838.24, or $308.56 each animal. From this is to be deducted about eight dollars per head for receipts from sales of horses, leaving for annual expenses, say, $300 per horse. The expense account, excluding attendance, would be, for twenty-five horses, $7,500, as against $1,500 for a similar amount of steam power, and, including attendance, $10,500, as against $2,439. Referring once more to the expense account of the Third Avenue Railroad, we find it working more economically than the average as given above. This company employs an immense number of horses, buys its supplies in large quantities, taking advantage of the market, and is able to do much better than could any individual or smaller capitalists. The following data were kindly furnished by Mr. Chas. S. Arthur: Average first cost of horses, per head,.. $157.50. Average price obtained when sold, (31 years later, 65.00. Cost of stabling, general expenses and incidentals, 18.00. Total annual expenses, including depreciation, 266.43. Add to the above the cost of harness, (not stated), say,..... 3.00. * State Engineer's Reports. j- This is about the figure on good railroads in the United States; on British roads the range is from 10 to 25 per cent. averaging very exactly 15 per cent. 24 The total annual cost of horse power, for comparison, 25 x $269.43 -$5,235.75, to which we add $3,130 for drivers, and we make a total cost per year of $8,365.75, to be compared with $2,439, the total annual expense of the road locomotive capable of doing an equal amount of work. The expense account when doing heavy work on the common road, under the described conditions, by steam power, is therefore less than 25 per centum of the average cost of horse power, as deduced from the total expense of such power in New York State, while if we take for comparison the lowest estimate that we can find data for in our whole country, we still find the cost of steam power to be but 29 per centum of the expense of horses. We may state the fact in another way: a steam traction engine, capable of doing the work of 25 horses, may be worked at as little expense as a teavm of six or eigh]t horses. Prospective. —Thus, thirty years after the defeat of the intelligent, courageous and persistent Hancock and his co-workers in the scheme of applying the steam engine usefully on the common road, we find strong indications that, in a new form, the problem has been again attacked and at least partially solved. It was formerly supposed that success in the transportation of passengers by steam on post routes would lead to the application of that motor to the movement of heavy loads and to agricultural purposes generally. When, after so long a trial, the experiment finally seemed to have failed of success, it was believed that steam could not be applied to heavier work on common roads. As we have now seen, however, it appears probable that the inventors of that day attacked the problem at the wrong point, and that, on the common road, the transportation of heavy loads by steam being accomplished with economical success, under ordinarily favorable circumstances, it may prove introductory to the use of steam in carrying passengers and light freight at higher velocities. Having examined in detail the capabilities of the road locomotive, and determined the value of steam traction on macadamized roads, and having obtained the measure of its economic superiority over horse-power, there remains to be considered the conditions which favor or retard its introduction, and to determine where it may be adopted without apprehension of failure. One of the most important of the pre-requisites to ultimate success in the substitution of steam for animal power on the highway iAs that our roads shall be well made. 25 As the greatest care and judgment are exercised, and an immense outlay of capital is considered justifiable, in securing easy grades and a smooth track on our railroad routes, we may readily believe that similar precaution and-outlay will be found advisable in adapting the common road to the road locomotive. It is undeniably the fact that, even when relying upon horse-power, far less attention has been paid to the improvement of our roads than true economy would dictate. With steam-power, the gain by careful grading and excellence of construction of the road-bed become still more important. The animal mechanism is less affected in its power of drawing heavy loads than is the machine. With the horse, a bad road impedes transportation principally by resisting the movement of the load rather than of the animal, while with the traction engine the motor is as seriously retarded as the train which follows it, and frequently much more, on soft ground. Steam, therefore, cannot be expected to attain its full measure of success on rough and ill-made roads; but where highways are as intelligently engineered and as thoroughly well-built as those on which the trials at South Orange were made, or where nature has relieved the engineer and the road-builder of the expensive work of grading, as throughout a very large extent of the western and southern portion of our country, we may expect to see the road locomotive rapidly introduced. The earliest and most perfect success of the traction engine, and its probable successor, the steam-carriage, may be expected to occur in those districts. Its great economical advantage over animal power, as exhibited above, its freedom from liability to become disabled by epizootic diseases, its reliability under all circumstances, and the many other advantages which are possessed by the machine, are already securing its rapid introduction, despite the difficulties arising from popular prejudice and unfamiliarity, from hostile municipal laws and other existing obstacles. We are learning that this motor, when it can be used at all, is comparatively inexpensive; that our roads are improved by it, and that the ancient idea of its conflicting with the interests of owners and workers of horses is only a superstition. WTe have found, by our experience with steam fire-engines, with the elevated railroad on Greenwich street, New York, and with railroads throughout the country, that the frightening of horses is but a temporary and a comparatively insignificant inconvenience. It would 26 seem to the engineer that the natural obstacles generally supposed to stand in the way have, after all, no real existence. The principal inconvenience that may be anticipated will probably arise from the carelessness or avarice of proprietors which may sometimes cause them to appoint ignorant and inefficient engine-drivers, giving them charge of what are always excellent servants, but terrible masters. Nevertheless, as the transportation of passengers on railroads is found to be attended with less liability to loss of life or injury of person than their carriage by stage-coach, it will be found, very probably, that the general use of steam in transporting freight on common roads may be attended with less risk to life or property than to-day attends the use of horse-power. This great economical revolution has now made a fair start, and is q progressing with most encouraging rapidity. We may anticipate its complete success at no distant period. Meantime every member of the engineering profession may aid its progress by exerting a personal Pa influence in favor of the improvement of our roads and the further C improvement of the road locomotive, which has, as we have shown, at last assumed a practical shape, and has exhibited wonderful power. L It is now at work in every portion of the civilized world, and the one establishment which constructed the engines above, described is now furnishing employment to 1000 working men, supporting a total population, probably, of 5000 people. Such a commencement having been made in a country like Great Britain, it is difficult to conceive how great may not be the future of - this branch of industry when the valley of the Mississippi and our - Western plains, the natural habitat of this motor, shall have become e finally a principal seat of its manufacture as well as of its employment. Stevens Institute of Technoloqy, Hoboken, N.J., Oct., 1872. -lie ERRATUM. On page 3, line twelfth from bottom, for "damages" read dangers. [The followiag valtable testimnotny has beern receivedc front G. W. DICK, Esq., of the Venicee.iills, Ross, Ohio, who has an.AvelinT q Porter t Six-horse Road Locomotive constanrtly at work7 J1..tV C. OJISTLER, E-H D'ewV York. DEAR SIR: We have used our Engine for almost all possible purposes: On the gravel road;-for drawing logs out of the wood;for threshing grain, and are now hauling pork in the streets of Cincinnati, over a boulder pavement. On the mracadamized road we draw from Hamilton to Venice, in-?t eluding wagons, 25,000 lbs. of coal, at one load-a distance of eleven miles. For logs in the wood, she is unequalled; we detach the engine fiom the wagon, and roll the tree on to the wagon, an inch at a time if we choose, and hold it there -a feat that h orse power will not perform. All who see her at this are amazed at the power we possess, alnd say she seems a thing of life. We drew a tree of an average girth of over 7 ft. and 73. feet inl length from our timber, about four miles distant, and we calculate it weighed eight tons or more. i q We have threshed nearly 40,000 bushels of grain with her since A harvest, and have found no place that we were unable to reach, no E matter what the grade or how deep the mud. Her facility for taking P, herself and thresher away, makes her a great favorite with the farmers, who have been bored with hitching their horses to a heavy steam engine, and spoiling them with the over load. Our greatest gain is in time, moving from place to place. In five minutes after the last sheaf is through, we are on the road; and we once moved 600 feet, and were threshing again in 10 minutes from the time the last sheaf was through at the last place (by a watch held onl us by a friend). We are now drawing pork in the streets of Cincinnati, and we draw from 12 to 15 tons at a load. I am, dear Sir, Dec. 5, 1872. Yours truly, G -V\7. DIOCK ~lgemqt for J,iessrs. TEL~Yi G' POR TER: WILLIAM CHURCHILL OASTLER, 43 Exchange Place, New York. t 7mnongst the rmactny seful pzu7poses to whichl the.VELING ( PORTER..OAD AND fARM ~OCOMOTIVE has been capplied, may be 7mentionred the followHauling Heavy Loads on the Common Road. Removing Agricultural Produce on ordinary Farm Roads, Breaking up Prairie and New Land, in conjunction with a gang of Ploughs, M~'~Breaking up Common Roadways previously to Macadamizing (with it large Ploughs). Rolling Telford, Macadam and other Pavements, and Consolidating'~'i Foundations (by removing driving wheels, and fitting the X I | engine with heavy cast rolling wheels). Tramway Engine for 4 ft, 82 in. Gauge (by removing driving rJ wheels, and fitting the engine with ordinary flange wheels), M~ I1 Driving Threshing Machines, and Removing same. Stump Pulling. ~ Hauling Logs from the Woods, and sawing same, Driving Brick-making Machines, ~W "} Mortar Mills.'" Circular Saws, and other Wood-working Machinery, " Cotton Gins, Pumping, b Lifting and Removing Heavy Goods (by the attachment of a Steam Crane in front of Engine). 0 -~'&c, &c,, &c, ig sent for Messrs. A VELIXG 4 PORTER: WILLIAM CHURCHILL OASTLER, 43 Exchange Place, New York. Steveln lni1ute of iTeohniology, A SCHOOL OF MXGUANMGAL INUINIRINGO Hoboken, N. J, [FounD D 81V ITM LAVE l onli a, A. ralans n$@ The second College year commences September 18th, 1872. FACULTY. HENRY MORTON, Ph. D., PRESIDENT. A. M. MAYER, Ph. D., Professor of Physics. Late of the Lehigh University, Bethlehem, Pa. R. H. THURSTON, C. E., Prof. of Engineering. Late of the U. S. Naval Academy, Annapolis, Mid. DE VOLSON WOOD, C. E., Professor of Mathematics. Late of University of Michigan. C. W. McCORD, A. M., Professor of Mechanical Drawing. A. R. LEEDS, A. ir., Professor of Chemistry. C. F. KR(EH, A. M., Professor of Languages. REv. EDWARD WALL, A. HM., Professor of Belles Lettres. The course of the Stevens Institute is of four years duration, and covers all that appertains to the profession of a.echanical Engineer.'By means of Workshops provided with excellent machinery, Physical Laboratories whose appointments are without an equal. and with the finest Cabinets of Instruments, every opportunity for the acquisition of thorough and practical knowledge is afforded. REQUIREMENTS FOR ADMISSION., Candidates for admission to the first year of the course should not be less than 16 years of age, and must be prepared to-pass a satisfactory examination in arithmetic, algebra, (including quadratic equations) geometry as given in Davies' Legendre and the six elementary propositions of plane Trigonometry. Candidates for admission to the higher classes must be prepared to pass a satisfactory examination in all the studies previously pursued by the classes which they propose to enter. Advanced students and men of science desiring to avail themselves of the appliances of the laboratories of the Stevens Institute, to carry on special investigations, may make arrangements to that end with the President. For farther particulars apply to the President, H. MORTON, Hoboken, N. J. e Tfollotwing vatluable testimony has been received fronm?, G. iW. DICKI, Esq., of the Frenice'iiills, -Ross, Ohio, who has ac,, Av. eling' Porteer Six-hlorse Rload Loco07motive cos071,6t?,ntly at worlc: MIr7. Ti': (C. QAd STLER,.;Vew Yor/k. DEAR SI;m WXe have used our Engine for almost all possible plurposes: On the gravel road; foi dracwing logs out of the wood; for threshinc, 1irain, anid arIe now hauling pork in the streets of Cincinnati, overi a. boulder pl:venient. On tle nIllactdrnized road we draw froml I-ltailton to Venice, including walgo ns, 25,000 lbs. of coal, at one load —:1 distiance of eleven -miles For loo's in thle wood, she is unequalled; we detach the engile fi'on the wagon, and roll the tree on to the wagon, an inch at a time if we choose, and hold it there -a feat that horse power will not perform. All who see her at this are amazed at the power we possess, and say slhe seemls a thing of life. WVe drew a- tree of anl average girth of over 7 ft. and 732 feet in length fiol: our tinlber, about four mliles distant, mclaid we calculate it weighed eieght tons or Inore. We hlave tlleshed nearly 40,000 bushels of 1,.rain with her since harvest? and have flound no place that we were unlable to reach, no ilatter whl:t the grade or how deep the nmud. Her ficility for takingl helrself and tlhrleshler arway, makes l-er a great, ct-fvorl ite ithe i hrnels, who hlave been bored whitli llitelling their hoi se;-, to.- heavy steam ell-ine, aillml spoiling them with the over lolad. ()lc glreatest gair is ir time, mloving from place to place. In five Illilnu es aftel the last shet f is thlrouo I1,' we are oil the road; and we once moved 600 feet, andl wei e tl:eshinlo alain in 10 minutes fromn the time thie last she:if was throuo'h.at the last ll:ce (by a watchl held onl us by a fi~ienld). %We are now drc.vin:ilog pork in the streets of Cincinnati, and we (di \aw fi'obn 12 to 15 tons iat a loid. I aim, dear Sir, D)ec. 5, 1872. Yours truly, G- -7 - DICI..dJIe7tt; fo-r d]e.ssi's. d T'IrLJ/VG cS PORTER: WILLI&AM CHURCHILL OA$TLER, 43 Exchange Place, New York.