Bhh9H i i i 1 ""**1®*!: ! ! A POPULAR TREATISE ON THE ELECTRIC RAILWAY. e. b. stillings & co., publishers, boston, mass. RESS OF E. B. STILLINGS & CO. 55 SUDBURY STREET. PREFACE. 5 the title of this book indicates, the subject of the electric railway is presented for your consideration. It has been the aim of the author of this work to treat the subject in a popular manner, and to describe the electric railway system in such language that the reader who is unfamiliar with technical terms can readily under¬ stand the construction of the apparatus, and the functions of various appliances used in the electrical propulsion of street cars. II. B. PRINDLE. If Boston, 1890. THE ELECTRIC RAILWAY. HE question of rapid transit in large cities is one which is daily growing in importance, and one which can¬ not be ignored. The steady growth of the business part of a city makes almost daily inroads upon the resident portion of a community, and forces the population farther and farther from the center and into the suburbs. A need, then, arises for some efficient method of transportation. The use of steam is precluded except on elevated roads ; the cable is only available under certain conditions ; horse cars are inadequate to meet the demands of a constantly in¬ creasing passenger traffic. Under these conditions electricity has been brought into active use, the results being best proved by the fact that surface roads operated by electricity have increased in number from three in 1885 to one hun¬ dred and thirty-seven, January 1st, 1S90, and one hundred and fourteen under contract for equipment. The history of the electric railway in the United States dates from Februarv, 1SS3, when a short exhibition line, operating the Van Depoele system, was built in Chicago, fol¬ lowed in November by experiments on the Mt. McGregor and Lake George Railroad at Saratoga Springs, with the Daft motor " Ampere." In 1884 two conduit systems were put in operation, the Bentley-Knight, at Cleveland, Ohio, 6 A POPULAR TREATISE ON on the East Cleveland road, and the Van Depoele at the Toronto exhibition. This was followed in 1S86 by the first installation under the Sprague system, the Richmond Passenger Railway, Richmond, Va., which was put in operation early in the spring of 1887. The first Thomson- Houston road was put into operation July 1st, 1888, at Crescent Beach, Mass. Experience has thus far proved that electricity is the best method which has been applied to street car propul¬ sion, and whatever objections have been urged against it have been shown in time to sink into insignificance, when compared to the great advantages obtained by its use, not only to the railway companies, but to the travelling public as well. Almost the first question that is raised when the subject of the electric railway comes up for consideration, is the danger to life on account of increased speed, and the electric current, and liability of the latter to cause fire. The daily press has unfortunately done a great deal in influ¬ encing public opinion, particularly in the last two respects, but happily facts show the incorrectness of its statements. The pressure of the current used in the systems, other than the series system, does not exceed five hundred volts, and in some cases is even lower, and as yet there is not an authentic case on record where a human life has been lost from contact with a railway wire carrying a current of this potential. Several cases have been reported, but upon investigation they have proved to be entirely without foun¬ dation. During the past year not one person has been killed in Boston by the electric current, and in New York City but .0061 of the violent deaths can be attributed to this agent. When the magnitude and great importance of electric lighting and power industries is taken into consideration, THE ELECTRIC RAILWAY. 7 there can be little question that there is not a single in¬ dustry capable of making such a good showing. When it is considered how few fires are caused by electric wires of any description, this objection will be found to be incon¬ siderable. The electric railway conductors, placed as they are over the tracks and insulated from their supports, the current from them cannot enter a building unless there is a contact between them and the wires used for some other purpose. Obviously, then, the railways themselves cannot be held responsible for damage done in this way. Every circuit, however, of whatever description, should be so carefully constructed that the liability to become displaced is reduced to a minimum, and should be provided with safety fuses wherever it enters a building. Additional security can also be obtained by suspending guard wires over the conductors, thus preventing falling wires coming in contact. As far as increased speed is concerned, there is no reason why it should bring increased danger. It takes but a short time to accustom the public to it ; and, as a result, better precautions are taken and more care exercised. In the matter of economy, the electric railway has established beyond question its superiority over horses. Naturally increased speed means fewer cars, a greater car mileage without any increase in the expense of conductors and drivers. Again, it is possible for one motor car to haul one and even two tow cars ; so that if necessity demands, carrying capacity can be greatly increased, pre¬ suming, of course, that the power station has been construc¬ ted with sufficient reserve force to meet this demand. A comparison of this reserve apparatus on which, when not in operation, depreciation is inconsiderable, and the expense of maintaining a sufficient number of horses to do the same 8 A POPULAR TREATISE ON amount of work, and it is obvious that it is in favor of the former. Then again, large cars can be used, by which the seating capacity can, perhaps, be doubled. These cars, however, need but one conductor and driver. \\ here horses are used there is a large number of individual gen¬ erators, each capable of doing a certain amount of work. In the electric railway these individuals are represented by a unit generator, the power plant, by which, it must be admitted, power can be more economically produced. Of every one hundred horse-power produced in the steam engine, at least sixty-two per cent is utilized in mov¬ ing the car. It is practically impossible to give an accurate average statement of the cost of generating power, so many local conditions enter the computation, and for the same reason the average power required by each car, as the weight of the car and passengers, the speed, curves, grades, all enter the calculation. The matter of repairs also depends upon local condi¬ tions ; but it can be safely said that electric railway appara¬ tus requires no more repairs than any other first-class machinery, provided due care is exercised. In three states for the year 18S8 the gross earnings and operating expenses of the surface and elevated roads were as follows : — GROSS OPERATING NET EARNINGS. EXPENSES. EARNINGS. CENTS. CENTS. CENTS. Elevated roads, New York State . . 5.OI 2.8l 2.20 Surface roads, New York State . 4-94 4.02 .92 Third Ward Elec. Ry., Syracuse ('89) 4.92 K) GO 2.14 Surface roads, Pennsylvania . 5-59 3.18 2.4I Surface roads, Massachusetts . . 5.10 4.2S .82 Boston & Revere Electric Ry. (1889) 4.70 2.71 1 -99 THE ELECTRIC RAILWAY. 9 Necessarily there are certain parts of the electric appa¬ ratus which will need replacement, but the immovable parts of the apparatus are practically indestructible and will last for years, the fields and armature for instance. The shells used in the bearings, the gears, and the trolley wheels will wear out, but can readily be replaced. However, they are susceptible of improvement, and continued trial and experiment will determine the best form and material for the auxiliary parts. In reliability the electric railway has exceeded all expec¬ tations. Snow has been considered the most formidable obstacle, but the operation of roads in many places during the past Year has settled that question beyond a doubt. Many of the roads, too, have made most excellent records so far as making trips on schedule time is concerned, one road having a record of more than 30,000 round trips with¬ out a single miss. Such facts as these are the best proof of reliability which can be offered. To be sure there is liability to breakdown and accident, but if a road is well constructed throughout of the best materials, and care is used it its operation, it can successfully compete with any system on this point. In the first consideration of the electric railway there comes the question of the original investment, the cost of installation. Approximately the cost per mile of double track for a first class road will be about $20,000 ; this including generating plant, steam and electrical apparatus complete; all line construction including paving, iron poles, 56 lb. girder rail, and one 26 foot and one open tow car per mile of track. These figures, of course, being subject to modifications, according to local conditions, wooden poles lessening the IO A POPULAR TREATISE ON cost of construction, a large number of curves increasing it, while heavy grades would require a power plant of greater capacity, and corresponding cost. Before entering into the subject of the electric railway, it will be well to look for a moment at the phenomena of what is called the electric current, and the terms used in connection with it. These are the volt, the unit of pressure ; the ampere, the unit of flow of current; and the ohm, the unit of resistance. The analogy of water offers the easiest comparison which can be made for the purpose of illus¬ trating these units. The unit of electro-motive force, or electrical pressure, or tension as it is sometimes called, is similar in nature to head of water. The difference in level or head is that which causes the water to flow. The electro-motive force or electrical pressure, using a similar comparison, is the force which causes the current to flow along the conductor. The unit of the rate of flow is the ampere, and is exactly comparable to the amount of water flowing through a pipe in a certain length of time. Every conductor offers a certain amount of resistance to the passage of electric current through it, and the unit of this resistance is called the ohm. The smaller the wire, of the same material, the greater the resistance it offers to the passage of the current. The work which is done by the electric current is ex¬ pressed in watts, the product of the volts and amperes ; for example, fifty amperes at ten volts pressure would equal five hundred watts ; or ten amperes at fifty volts pressure would equal five hundred watts. Seven hundred and forty-six watts constitute one electrical horse-power ; consequently the amount of work which a dynamo machine is capable of doing would be expressed by the equation, horse-power equals volts times amperes divided by seven hundred and forty-six. THE ELECTRIC RAILWAY. THE ELECTRIC RAILWAY. Briefly the system of electric street car propulsion con¬ sists in the production of the electric current by mechanical means, its transmission through conductors to the electric motors on the cars, where it is again transformed into mechanical energy, which gives the motion to the car. THE POWER STATION. The subject, then, naturally begins with the power station, a plan of which is shown in the drawing on page 13 ; a reproduction from a photograph of the power station at Omaha is also shown 011 page 15. The equipment of a power plant comprises — First:—The Steam Plant. Second :— The Electrical Apparatus. Power Station, Scranton, Pa. Sprague System. THE ELECTRIC RAILWAY. '3 Tn d i_d d 111 d i_d r '1 Plan of Power Station. H A POPULAR TREATISE OX The steam plant is made up of the necessary boilers, steam pumps, feed water heaters, etc., and a suitable engine or engines for driving the dynamos used for gener¬ ating the electric current. Their arrangement can be readily seen from the plan on page 13, and from the interior views on pages 12 and 15. In small plants the dynamo machines are usually connected directly by belting to the engines, but in larger ones it is the general custom to have the engines belted to a countershaft, to which the dynamos are connected by friction couplings, rendering it possible to throw a machine in or out of action as the number of cars is increased or decreased. The plan on page 13 represents one method of arranging power stations. B, B, B, B, are the boilers, placed, as can be seen from the drawing, in a boiler room and separated from the other apparatus by brick walls. E represents the engine, which is belted directlv to the counter shaft. D, D, D, D, are the dynamos, or generators as they are usually termed when used for elec¬ tric railway work. They are belted to the counter shaft and so arranged that by means of friction clutches they can be started and stopped at will. With water power the electrical apparatus remains unchanged, the engines, boilers and auxiliary devices being replaced by water wheels. In the power station is shown one of the greatest advantages of the electric railway, for it may be located where water power is available, or if steam be used it may be situated advantageously to the securing of water, enabling compound condensing engines to be used, thus reducing the consumption of coal per horse-power hour ; or if fuel be the more important consideration, located where coal can be procured at the least possible cost for transportation and cartage. Power Station, Omaha, Neb. i6 A POPULAR TREATISE ON THE ELECTRICAL APPARATUS. The electrical apparatus consists of the dynamos or generators, as they are usually called, which supply the current for the cars, and the necessary appliances for manipulation. The principal parts of a dynamo are the armature, commutator, and field magnets, as shown in out¬ line diagrams Nos. i and 2. The field magnets consist of iron cores wound with layers of insulated wire. The armature consists of an iron core' made up of separate coils of wire, the ends of which are connected to the commutator, which is made up of strips of copper separated by some non-conducting material, mica being generally employed for the purpose. This armature is driven from the engine by a pulley placed 011 the end of the shaft opposite the commutator, and its revolution pro¬ duces a current of electricity which is taken off by means of conductors, copper or carbon, called brushes, placed against the commutator and held in position by springs. The explanation of the phenomenon is based upon the fact that the rotation of a conductor, the armature, properly Thomson-Houston Railway Generator. i8 A POPULAR TREATISE ON F F B Diagram No. 2.— Outline showing Armature Winding and Commutator. F, F—Field Magnets. A — Armature. C—Commutator. B, B—Brushes. situated in proximity to the poles of an electro-magnet, the field magnets of the dynamo, will produce in this con¬ ductor a flow of electricity the direction of which, the strength and other qualities de¬ pend upon conditions, the ex¬ planation of which is beyond the scope of this work. The principle of an electric motor, which e will be referred to in succeeding pages, is the converse of the above, that is, if a cur¬ rent of electricitv is made to flow in a con¬ ductor, the armature, properly situated with regard to the poles of an electro¬ magnet, the field magnets, the conductor will tend to move. In a motor this movement is made one of revolution. The common forms of dy¬ namos are series, shunt and compound wound, shown in diagrams 3, 4 and 5. In the series machine the armature and field coils are connected in what is called series, that is, the same amount of current passes through the armature, field coils and motors. In the shunt wound dyna-Diagram No. 3._ Series Wound Dynam'0. mos the field coils are connected in multiple, or shunt THE ELECTRIC RAILWAY. l9 with the armature, that is to say, the main current passing from the positive brush divides, the greater portion going through the armature to the out¬ side circuit, and the remainder through the field coils, back to the opposite brush, see diagram No. 4. When this machine is used for lighting or power pur¬ poses it is necessary to regulate the amouut of current passing through the field coils. This is accomplished by putting into the circuit a variable resistance (for instance, a number of coils of wire), by which the strength of the field magnets can be va¬ ried as the load on the machine increases or decreases ; or, in Diagram No. 4. — Shunt Wound Dynamo. Diag. 5. — Compound Wound Dynamo. other words rendering the machine capable of supplying more or less current as the number of cars or amount of power required by them in¬ creases or diminishes. The great objection to the shunt wound machines is the fact that they require the constant attention of the operator, who is obliged to observe the cur¬ rent indicator closely, and to vary the resistance of the field magnets in proportion to the demands made upon the dy- 20 A POPULAR TREATISE ON namo. To obviate this constant attendance the compound wound machine is used, see diagram No. 5. This machine is identical with the shunt wound machine ; but it has in addition an extra coil of wire wound around the field magnets, through which the main current Railway Generator. Sprague System. passes before it goes to the line. It has been found in practice, however, that it is also desirable to use a rheostat in connection with generator for electric railway work, as the demands made upon them by an increase in the number of cars and the power required by them are at THE ELECTRIC RAILWAY. 21 times very great, and the fact that the resistance of the field magnets varies as the load is increased. Machines of this class will produce a current of uniform pressure, and are the best adapted and generally employed for street railway purposes. General practice in this class of work is to larger dynamos, one hundred horse-power machines being now used, and dynamos of two hundred and fifty horse-power being under construction by one of the leading electric companies. The use of the carbon brushes is now con¬ sidered to be the best practice, as the wear on the commu¬ tator is thereby greatly reduced. The next subject for consideration after the dynamos is the apparatus necessary for its practical and easy manip¬ ulation. 22 A POPULAR TREATISE ON THE SWITCH BOARD. The current generated by the dynamo, as shown in diagram Xo. 6, page 23, is conducted to the switch board, where are arranged a number of appliances. Diagram No. 6 is a plan of a switch board for one railway generator, and is amply sufficient to illustrate the several devices. Any increase in the number of dynamo machines requires simply an increase in the number of appliances, the arrangement remaining practically as is here shown. As is indicated by the arrows in the illustration the current flows from the armature of the generator through series coil, thence through the lightning arrester, through the station switch to the overhead line passing out over the line to the trolley, through the trolley arm to the motors, back through the rails, then through the auto¬ matic circuit breaker, the ammeter and station switch, through the connection board and fuse, back to the arma¬ ture. When one or more machines are connected in multi¬ ple, another wire is run from the junction of the series coil wire and positive brush wire, through the station switch to the equalizing bar. SWITCH BOARD APPLIANCES. The nature and functions of these various appliances may be briefly described as follows : The current indicator consists of a pair of electro¬ magnets, suspended between which is a needle traversing a THE ELECTRIC RAILWAY. 23 DIAGRAM No. 6. Tc.~Ra.tls Diagram of Switch Board. a—Circuit Breaker. b—Current Indicator. c—Station Switch. d—Rheostat. e—Lightning Arrester. 24 A POPULAR TREATISE ON graduated scale. When the current passes through the magnets the needle is deflected, the deflections being exactly dependent upon the amount of current flowing. Thus it is possible to ascertain from this instrument the amount of current which is being generated by the dynamo, or, in other words, the amount of work it is doing; this, of course, representing the amount of power required by the number of cars in operation. The feeder or connection board consists of metal con¬ nections, in the circuit of which are interposed what are called " fuses." These fuses consist of strips of fusible metal and are so proportioned as to carry a certain amount of current. An excess of current beyond this amount causes them to melt, or " blow out" as it is termed, which opens the circuit and prevents the excess from doing any injury to generators or motors. The automatic circuit breaker consists of a pair of electro-magnets and a switch governed by a powerful spring. In the normal condition of load this switch is closed and held from opening by the armature of the electro¬ magnets. When, however, the current exceeds a normal amount the magnets act upon the armature, releasing the switch which is quickly thrown open by the springs. This shuts the current oft' from the generators and motors and obviates all liability to damage. The volt meter forms another part of a switch board equipment and consists of an instrument for determining the electro-motive force or electrical pressure of the cur¬ rent. It is in some cases connected to various points on the outside circuit so that at any time the operator may- determine just what the pressure is at these points. It is not necessary, however, that this should be done, as the potential of the dynamo can be ascertained and the pressure THE ELECTRIC RAILWAY. 25 at various points calculated from it. The apparatus con¬ sists of a needle acted upon by an electro-magnet, the needle traversing a scale divided into degrees (each degree representing a certain number of volts), from which the electro-motive force or pressure can be readily computed. Interposed in the main circuit is also an appliance known as a " lightning arrester." It has been found ad¬ vantageous in both electric lighting and power installations to make use of this instrument to prevent the lightning dis¬ charges doing any injury to the generators. The action of this instrument depends upon the well-known principle that the arc formed by the passage of an electric current from one conductor to another, these conductors not being in contact, can be broken, if the influence of the electro¬ magnet is brought to bear upon it. Its construction is such that a lightning discharge entering upon the wires has to jump an air space which is situated in a magnetic field which blows out the arc. The main current passes through the electro-magnet and maintains a constant magnetic field, the other connections being such that the lightning is led directly to ground where it can do no damage. 20 A POPULAR TREATISE ON LINE CONSTRUCTION. The next topic for consideration is the construction of the outside line. This consists primarily of what is known as the "trolley wire " or the overhead conductor. (See diagram Xo. 7.) The current as shown by the arrows is taken from the dynamo to the switch board, thence directly to the trolley wire or conductor, passing along in the direction shown by the arrows, a portion being conducted off at the points (t) (t) (the remainder going on to supply the other cars), where it passes down through the trolley arm, along the wires concealed in the car to the motors, through the motors, thence to the rails as indicated on the diagram, back to the switch board and through the various appliances used there to the dynamo, thus making a complete circuit. Where long lines are used wires are run out from the station and connected to the overhead trolley wire at suita¬ ble points, in order that the electrical pressure may be kept practically constant. These wires are known as " feeder wires," and not only serve the above purpose, but also permit doing what is now generally considered the best practice, dividing the line into sections, each section having its own source of supply. The advantages of this are obvious. Where the trolley wire consists of one continuous conductor a break in it throws out of action every car except those between the break and the power station. Then again, as soon as such a break is repaired, the cars which have been stopped all start up again at practically THE ELECTRIC RAILWAY. DIAGRAM No. 7. 2S A POPULAR TREATISE ON the same time, which makes an enormous demand upon the power station for the necessary current. When, how¬ ever, the overhead conductor is cut up into sections, and a J (oj (o) ; kL- ELEVATION T Rail. Rail Connections. number of cars are stopped for some reason, the current can be put on these sections one at a time, which brings on the load gradually and obviates the necessity of subjecting the dynamos and engines to sudden strain. wnw*.,.. Rail. Rail Connections. RAIL RETURN. The rails are used for the return circuit, various methods, as shown by the accompanying diagrams, being employed for rendering it complete. In some cases the 1 vvTfte—" J2jT19 I MAKE SOLDER CONNECTIONS Supplementary Wire. THE ELECTRIC RAILWAY. 29 two rails are connected together by copper tie wires soldered to each rail at joints. In other cases what is known as a " supplementary wire" is used, shown in diagram Xo. 7. This supplementary (s s) wire consists of an unbroken conductor running from the extreme end of the line back to the power station. At each joint (j j) on both rails wires are soldered which are also soldered to the supplementary wire, thus making a com¬ plete metallic cir¬ cuit for the re¬ turn of the current to the pow- The system which is most ex¬ tensively used at the present time is what is known as the single trolley system, the current being taken out on the overhead conductor and returned to the station by the rails. The construction of the overhead lines so far as switches, frogs and turn¬ outs are concerned,is reduced to a matter of much simplicity and neat¬ ness, the work being done with few auxil¬ iary wires. Trolley Stand and Arm. Short System. The two wire, or double trolley system is also in successful operation on many roads. (See pages 30, 32.) In THE ELECTRIC RAILWAY. 3» this system, as the name indicates, an entire metallic over¬ head circuit is used, the second suspended wire taking the place of rail return or auxiliary ground wire, which obviates grounding the current. The trolley arm carries two trolley wheels or sliding contacts which are thoroughly insulated from each other. The path of the current is along one of the overhead wires to one of the contacts, down one side of the trolley arm, through the motors, thence through the oppo¬ site side of the trolley arm to the second contact, along the second trolley wire back to the power station. This system is particularly suited to long continuous lines. The next topic for consideration is the car. In electric railway systems the car body is not neces¬ sarily of different pattern from that where horse-power is employed, the only difference being that it has to contain the necessary wires for conducting the current to the motors, and the wiring for the incandescent lamps by means of which the car is lighted. Double Trolley Construction. Short System. THE ELECTRIC RAILWAY. 33 THE MOTOR. The construction of the electric motor for street car propulsion is shown on pages 33, 34, 35. The motor technically is simply an appliance for the transformation of electrical into mechanical energy, and in action is just opposite to a dynamo machine. Railway Motor. Thomson-Houston System. The armature of the dynamo machine is caused to revolve by mechanical means, and generates a current of electricity which is capable of.doing work. This current of electricity is sent out over the line and into the motor, the passage ot the current through which produces the rotation of the armature, which motion is communicated by means of gears and pinions to the axle of the car. 34 A POPULAR TREATISE ON THE MOTOR TRUCK. The construction of the motor truck as used for electric railway work is fully shown by cuts of trucks on pages 36, 37 and 3S, which it will be observed are much heavier and much stronger than those employed where horses are used. THE ELECTRIC RAILWAY. 35 One end of the armature shaft of the motor is provided with a pinion which communicates its motion by means of a large gear to an auxiliary shaft provided with a pinion which in 36 A POPULAR TREATISE ON turn communicates its motion to another large gear placed upon the car axle. In order to insure the parallelism of these gears and pinions one end of the motor is fastened directly to the car axle, the other end is supported by springs, which permits of a movement of the motor and does away with the jar and strain which would other¬ wise occur on the starting and stopping of the car. The trucks here shown are provided with two motors, but single motor trucks are also extensively used. In the early practice of electric railway construction one motor was generally em¬ ployed, placed above the car platform and connected to the car axles by means of sprocket chains and belts, but this did not prove satis¬ factory. The best position for the motor thus far seems to be underneath the car body, and while this method cannot be said to be free from objec¬ tions it certainly has proved to be much superior to any other place. The objections are, that the motors are exposed to a great deal of dirt, A POPULAR TREATISE ON J'": J*' iM 'J** I.Ai.1 fj} 11,1 ■ i-'1, , i fj.' « B 1 ' " ' , CO dust and water, although protect¬ ed by iron pans, and canvas side pieces, and are not easily accessi¬ ble for repairs. Then, too, they are entirely con¬ cealed from sight, so that it is im¬ possible for the operator to see if they are working properly. In the con¬ struction of elec- I trie motors for street cars the question of gear¬ ing is air impor¬ tant one. It should be as nearly noise¬ less as practica¬ ble to make it, and of such mate¬ rial as will give the most econom¬ ical results. The larger gears are usually made of iron with cut THE ELECTRIC RAILWAY. 39 teeth. Various metals and combinations of metals have been used for pinions, steel and rawhide, gun metal and others. It is difficult to say which is the most suitable ; experience alone can decide this question. Worm gearing has been used to some extent, and with satisfactory results. A desire to do away with gearing has led to experiment with friction clutches, but thus far it has not been put in general use. Although the problem is one presenting many difficulties, owing to the rapid revolution of the armature, a friction clutch which would obviate the use of intermediate gearing would be of great value, and will doubtless soon be produced. In street railway practice at the time of starting the motor a large amount of current is consumed in bringing it from a state of inertia, or no efficiency, up to its maximum efficiency. This has led to the discussion of the importance of a constant speed motor, which should be connected to the axle of the car as at the present time, by some sort of a friction coupling, by which the car can be started and stopped with as much ease and at the same rate as is now done. A certain amount of power would, of course, be lost between the revolving and stationary parts of the friction clutch, and the wear of the clutch would have to be taken into consideration. This, however, is over¬ balanced on the other hand bv the large amount of current consumed in starting and by the wear 011 the gears and pinions, which is at the time of starting and stopping very large. While no device has yet been put in practice, perhaps the present system seems amply sufficient for present needs, the subject is one of much importance, and one which before long will doubtless receive the attention of electrical engineers, whose inventions will result in the production of Cross Suspension Method, Cleveland, O. Sprague System. THE ELECTRIC RAILWAY. 41 some suitable device by means of which the motor can be operated at all times at a maximum efficiency. This would also obviate the use of as large rheostats as are needed at present, and reduce the number of wearing parts and appliances very materially. Another point to be considered in electric traction is the question of which is the most advantageous to use, one or two motors. Where two motors are used and connected in multiple, it is impossible that one motor shall do exactly one-half of the work, for it is not possible to manufacture two motors which will act under load in precisely the same manner; then again the use of one motor, if connected to both axles, will give as good results as two, so far as traction is concerned, reduces the number of gears and pinions, and in fact all the wearing parts, exactly one-half. The expense of repairs and maintenance on street car motors is confined mainly to the small parts, and their reduction one-half would certainly reduce the operating expenses a very considerable amount. It may be said that if there is but one motor on a car, and it should be seriously impaired, the car would have to stop. This, however, is more than overbalanced by the economy of operation, and the great reduction of the parts which would have to be replaced, which have been previously mentioned. There are several methods of governing the speed of the electric motor. In some systems a rheostat or resist¬ ance is connected in series with the armature, this rheostat being governed by mechanism placed at each end of the car, known as the " controller stand." This controller stand is provided with a handle, by means of which the amount of current which flowsffirrough the motor and the speed may be easily regulated. In other systems the resistance is not employed, the Single Bracket Construction, Brcckton, Mass. Sprague System. THE ELECTRIC RAILWAY. 43 OTEL windings on the magnets of the motors being connected in such a way as to offer at the time of starting the car a large resistance, which is gradually ? reduced as the speed of the motor is increased. Each car is provided with a reversing switch, which is shown in the diagram of the car wiring, by means of which the direction of the current may be changed, which results in changing the direction of the rotation of the armature, thus entirely obviat¬ ing the necessity of turntables, or anything of like nature, and checking the car in a case of great emergency to avoid acci¬ dent or collision. Each car is also provided with lightning arresters embodying the same principles as those used in the power station, by means of which all danger from light- o o ning discharges is obviated. There is a popular impression that there is great danger from electric cars during storms ac¬ companied by thunder and lightning, but the impression is a false one, as the lightning ar¬ rester is an ample protection to the car and passengers ; there not being an authentic case on record where injury has been done to either by the discharge of lightning. Single Bracket Construction, Omaha, Neb. Thomson-Houston System. THE ELECTRIC RAILWAY. 45 OVERHEAD CONSTRUCTION. In the overhead construction there are three methods used: the "cross suspension," "single bracket" and " double bracket." The most common of these is the " cross suspension." In this method of construction the overhead conductor is supported by cross wires attached to poles placed opposite each other at the curb-line on each side of the street at a distance of one hundred to one hundred and fifty feet apart, depending, of course, upon the condition of the thorough¬ fare, number of curves, etc. THE ELECTRIC RAILWAY. 47 The main conductor is supported from cross wires by means of pieces of metal, called " ears," being in turn fastened to the cross wires, some insulating material being O & placed between the ear and cross wire. This insulator of an insulator being used between the main conductor and the bracket as is employed in the "cross suspension" method. The third method is what is known as the " double bracket method " and is employed where straight -double tracks are used and the distance between the tracks will permit. The two conductors are suspended oyer the cen¬ ters of the tracks by means of double brackets fastened to poles which are set in the space between the two tracks, the same insulation being used as in the two previous forms of construction. The accompanying diagrams show the method of curve construction for both single and double tracks. The con- prevents any current from passing over from the cross wires to the poles. f SECTION OF STREET SHOWING SIDE POLE AND BRACKET. The second method of overhead construction is what is known as the "single bracket system," and is most generally used where the tracks are placed on the side of the street near the curb. In this case the conductor is suspended over the mid¬ dle of the track from brack¬ ets firmly attached to poles placed on either side of the track as may be found most advantageous, the same sort Double Bracket Suspension, Atlantic City, N. J. Sprague System, THE ELECTRIC RAILWAY. 49 ductors are supported at the beginning of the curve by the ordinary cross wire, and in the curve itself by auxiliary wires radiating from iron poles and fastened to the trolley wire at various points, as shown below : . CURVE CONSTRUCTION. For the overhead system various forms of poles may be used ; those most commonly employed, however, being of wood neatly painted, or iron. The iron pole is unques¬ tionably the best which can be used for the purpose and can be made the subject of much fine work, and of such 5° A POPULAR TREATISE ON form as to be by no means a conspicuous feature of the system. The iron poles are generally made of sections of iron pipe carefully shrunk together, protected at the top by an insulated cap and a cap also being placed on the pole where it enters the earth. It is a general custom to set these'poles in broken rock and cement, giving them a slight angle away from the tracks, so that when the cross wires are drawn taut the poles present a neat appearance. The single and double bracket methods, each possessing advan¬ tages under certain circumstances, have been generally THE ELECTRIC RAILWAY. 51 used in the United States, and in some instances are of exceedingly fine appearance, being carefully designed and ornamented. At Atlantic City and Washington are excel¬ lent examples of the double bracket system, handsome iron poles and brackets having been used. Thus far in the history of the electric railway the most generally adopted method consists in the generation of electricity by mechanical means, and its transmission by overhead or underground conductors to the motors as previ¬ ously described. A desire, however, to do away with overhead conductors, and to render each car independent, has led to the development of the storage battery system. The batteries consist of lead plates, and are charged from a dynamo machine. They can then be drawn upon for current for a variable time, dependent upon their capacity. In practice a large central generating station is established as in other systems, or current obtained from a local light¬ ing station. The batteries are charged and placed in the cars, which thus become independent electric locomotives, so to speak, capable of running on any track until the supply of electricity in the storage cells is exhausted. In recharging, the batteries are either removed from the car, which may then be supplied with a second set and put into immediate use again, or the)- may be charged in the car which neces¬ sitates a larger car equipment, as the operation consumes some time. It is a question of larger car equipment or more sets of batteries. STORAGE BATTERIES. Snow Broom. Thorn son-Houston System. THE ELECTRIC RAILWAY. 53 There is one feature of the electric railway which is now receiving careful consideration, and that is the employ¬ ment of independent electric locomotives, thus doing away to a great extent with motor cars. While this is not nec¬ essary on small roads it is so in the larger systems. Take for instance, a large system operating a thousand cars, five hundred open and five hundred closed. Each of these cars must be ready for operation at all times, so that practically, one-half the electric equipment is lying idle. This means, then, a large investment in apparatus which must be kept always in repair, on which there is a constant though small depreciation, and from which no returns are coming. The use of independent electric locomotives would obviate this necessity, and would render it possible to run even three and four car trains, and would reduce the matter of changing from open to closed cars, as is often necessitated by extreme changes of weather, making it a matter of much simplicity. In the operation of surface roads by electricity snow has been generally considered to be an unsurmountable barrier, but the operation of roads in various parts of the United States during the past winter has been so successful that this matter is now no longer surrounded by doubt. An electric snow plow is shown on page 54, and a snow broom on page 52. The latter, beside the equipment for propulsion, has two stationary motors by which the brooms are worked. Many who are familiar with electric railway construc¬ tion predict that ere long the overhead system will be entirely done away with, some other method taking its place. Whether this will be the conduit is open for dis¬ cussion. The conduit method has not proven thus far to be particularly adapted to climates where rain and snow are at all prevalent, and it is exceedingly difficult to build Snow Plow. Sprague System. THE ELECTRIC RAILWAY. 55 one in which there will not be a great loss from leakage and short circuiting. Conduits themselves are exceedingly expensive to construct, and cannot be operated unless there is a system of sewerage in connection with them, and in case of damage are exceedingly difficult to repair. One method has been proposed, namely: that of using the two rails for one conductor, and a third rail placed between these for the other, conducting the current from the third rail by some suitable arrangement. This, of course, would require the use of currents of low potential, so that the danger of leakage and short circuiting would be reduced to a minimum. It is proposed to effect this by means of the use of currents of high potential, the pressure of which shall be reduced by passage through transformers from which the current is conducted to the rails at a sufficient number of intervals to insure its being practically constant. This would necessitate the use of alternating currents. There can be but little question as to the future of the electric railway, its practical and commercial success has been such as to establish beyond question that electricity is the superior to any known method for the propulsion of street cars. It is a system which is as easily adapted to elevated as surface roads, and one which in time may sup¬ plant steam. It is a system which can be more generally adapted to local conditions, and can be extended to cover a greater territory at less cost for construction and mainte¬ nance than any other which has been brought before the public. Railway Switchboard. Referred to on pages 22 and 23. à, a, a — Circuit Breakers. b, b, b — Current Indicators. c. c, c — Station Switches. d, d, d — Rheostats. 6, e, e — Lightning Arresters. (From Electric Power). ELECTRIC STREET RAILWAYS OF AMERICA In Operation and in Process of Construction May ist. * Under Construction. Location. Adrian, Mich. Akron, Ohio Albany, N. Y. Alleghany, Pa. Alliance, Ohio Americas, Ga. Ansonia, Conn. Appleton, Wis. Asbury Park, X. J. Ashe ville, X. C. Atlanta, Ga. Atlantic City, X. J. Attleboro, Mass. Auburn, X. Y. Augusta, Me. Baltimore, Md. Bangor, Me. Bay City, Mich. Bay Ridge, Md. Beverly, Mass. Binghampton, X.Y. Birmingham, Ala. Bloomington, 111. Boston, Slass. Brockton, Mass. Brooklyn, X. Y. Buffalo, N. Y. Camden, N. J. Canton, Ohio. Chattanooga,Tenn. Chicago, 111. Cincinnati, Ohio Cleveland, Ohio Col. Springs, Col. Columbus, Ohio. Council Bluffs, la. Dallas, Texas Danville, Va. Davenport, Iowa. Dayton, Ohio Decatur, 111. Denver, Col. Des Moines. Iowa Adrian City Belt Line Electric Ry. Co. Akron Electric Ry. Co Watervliet Turnpike and Railway Co. Albany Railway Co. Observatory Hill Pass. Ry. Co. . Alliance St. Ry. Co. Amerieus Street Railway Co. Derby St. Ry. Co. Ap. Electric St. Ry. Co. . Seashore Electric Ry. Co. Asheville Street Railway Atlanta and Edgewood St. Ry. Co. Fulton County Street Railway Co. Pennsylvania R. R. Co A., Xo. A. & Wrentham Street Ry. Co. Auburn Electric Railway Co. . . ' Augusta, Hallowell