Some Early Traction History

SOME EARLY TRACTION HISTORY

By Thorburn Reid

The modern electric railway may be said to have been born in the year 1835 in the small American village of Brandon, in Vermont, with the village blacksmith, one Thomas Davenport, as sponsor. The child was weak and puny, and was destined to languish long in obscurity and neglect, passing through many vicissitudes before it finally attained the strength of vigorous development.
At that time, and for many years afterwards, the primary battery was the only available source from which electric energy could be obtained for driving motors. The initial cost of the primary battery was very high, and the cost of the chemicals consumed in it was about sixteen times that of the coal required to produce the same amount of electrical energy through the medium of the steam engine and the modern dynamo. This great expense, combined with the difficulty in handling the liquids and more or less fragile materials used in the construction of the battery, constituted an insurmountable obstacle to the commercial use of the electric motor for traction purposes.
Notwithstanding this, however, many inventors worked at the problem during the period from 1835 to about 1873, when the power-driven dynamo commenced to take shape as to make it commercially available as a source of electrical energy for driving motors. During these years many of the details were worked out and methods employed which are still used in the best modern practice.
Following Davenport, who drove his motors with current supplied by primary batteries carried on the car, came Robert Davidson, of Aberdeen, Scotland. He built a powerful electric locomotive which made a number of trips on Scottish railways and was finally destroyed, presumably by some engineers who feared that their own machines would be superseded by the new invention. He, too, used primary batteries carried on the locomotive.

Davonport's Electric Railway Model, 1835
The next experiment on a large scale was made in 1850 by Prof. C. G. Page, of the Smithsonian Institution at Washington, D. C., who, like Davidson, worked at the idea of an electric locomotive. His motor was a reciprocating one, two solenoids being used to draw back and forth a soft iron piston rod, which was connected to a fly-wheel by means of a connecting rod and crank. Prof. Page tried several other motors of the same general character and succeeded in obtaining considerable speed and power, but his experiments were given up, as those of his predecessors had been, on account of the excessive cost of batteries as a source of electrical energy.
Three years previous, in 1847, however, Professor Moses G. Farmer had operated a small experimental model of an electric car, at Dover, N. H., U. S. A , and later, during 1850-51, aided by Mr. Thomas Hall, he exhibited at Boston, Mass., a model road on which a car ran back and forth, and automatically reversed its own direction of motion at each end of the road. This was subject to the same drawbacks as previous devices, due to the use of batteries. It is interesting, however, as one of the first known instances of the use of the rails, upon which the car ran, as a means of conveying the current from stationary batteries to the motor on the car. This model also embodied, perhaps more or less accidentally, the principle which is now almost universal, of running the motor at a high speed and gearing it down to a lower speed on the car axle, thus making possible the use of a smaller and cheaper motor for the power supplied.
As has been just said, all these experiments were foredoomed to failure, because the enormously expensive primary battery had to be used as a source of power. It must be remembered that at that time the steam-engine was in its youth and the steam locomotive in its infancy. The law of the conservation of energy was known to but few, and fewer still understood or accepted it. The discovery of Ohm's law had been published but a few years, and a working knowledge of its use was mainly confined to mathematicians. The principles of motor design were not at all understood, while the dynamo had not been invented. It was a period, however, when inventors, scientists, and engineers were startling the world with new discoveries and wonderful achievements in the use of the energy of steam and other sources of power, and things that on one day had not been even thought of were settled facts and almost commonplace on the next. It was natural, therefore, that these inventors should attack a problem the impossibility of solving which their lack of knowledge of the laws of electricity and of energy prevented them from foreseeing.
In 1864 the modern dynamo was born, but no one dreamed then, nor for many years afterwards, how large a part it was destined to play in the industrial progress of the world. Earlier inventors, discouraged by their lack of success, had turned their powers into other fields, and did not realise that the one great obstacle to the commercial development of electric traction, the prohibitive expense of a battery as a source of power, had been removed with the advent of the far more economical dynamo.
It was not until eleven years later that any appreciate advance was made in the development of electric traction. Just as in 1835 a village blacksmith stood sponsor at the birth of electric traction, so in 1875, forty years later, a poor mechanic, George F. Green, living in the small American country town of Kalamazoo, in Michigan, rescued and revived the abandoned and almost forgotten idea.
Green's motor was a very primitive one, the armature consisting of an iron bobbin on which was wound a coil of fine wire, connected to a two-part commutator, which reversed the current in the armature twice during a revolution. He conveyed the current to his motor by means of an overhead line. using the track as a return. He used a battery as his source of power as he was too poor to buy a dynamo and did not know how to make one, although he perfectly well knew that his power must be derived from a dynamo if his invention was to become a commercial success.
About this time Mr. C. J. Van Depoele, who was afterwards one of the foremost inventors engaged in rendering electric traction practicable, was making experiments with motors; but it was not until 1883 that any public exhibition was made of his inventions in this direction.

The Siemens & Halske Electric Railroad, shown at the Berlin Industrial Exhibition in 1879
In 1879 Mr. Stephen D. Field, in America, and Messrs. Siemens and Halske, in Europe, both were engaged on the problem. Field was handicapped by lack of money and by the fact that it was necessary for him to order a dynamo from Europe, as none suitable for his purpose was to be had in the United States. Siemens and Halske succeeded, however, in building what was probably the first electric railway on a practical scale. They used what is now called the third-rail system for conveying the current to the motors, this rail being laid midway between the two upon which the car ran, and current being taken from it by means of a sliding shoe. Field was the first to suggest the use of a conduit for carrying the wires conveying the current, the method which is now so extensively used in New York City.
The success of Siemens's road in Berlin incited many inventors to work at the same problem. In the succeeding year Egger showed a model electric railway in which the current was conducted to the motors through one of the rails upon which the car ran, and returned through the other; but this was a step backward, since this would have meant a shock to a horse or man who might happen to touch both rails at once. In 1880 Edison came into the field, but he does not appear to have made any radical improvements.
In Europe, Siemens was driving ahead with tremendous energy and enthusiasm, being engaged in the development of various schemes, including an elevated road with the working rails as conductors. He proposed running the speed up to forty miles an hour, and for this purpose was the first to suggest placing the armature of the motor directly on the axle of the locomotive.

The First Electric Railway with an overhead wire at the Paris Exposition of 1881

A car on the first commercial electric railway, installed at Lichterfeld, Germany, in 1881, by Messrs. Siemens & Halske, of Berlin
In May, 1881, the first commercial electric road, as distinguished from the previous experimental roads, was opened to the public at Lichterfeld, Germany. The next commercial electric road to be put in operation was opened to the public in 1883 at Portrush, in Ireland, using the third-rail method of supply. A noteworthy advance was made there in the use of turbines for driving the dynamos supplying the power.

The water power of the Portrush Electric Railroad, Ireland, 1883

A trolley car in Paris in 1881
From this time on progress was rapid, and advances were made simultaneously by many different inventors. The idea of reinforcing the conductivity of the rails by auxiliary conductors was used in 1883.
Up to 1883 progress in the direction of commercially developing electric traction was mainly confined to Europe, but in that year American inventors assailed the problem with characteristic enthusiasm and recklessness. The Electric Railway Company of the United States, working under patents of Field and Edison, built an exhibition road for the Chicago Railway Exposition, which showed nothing new except auxiliary copper conductors to reinforce the conductivity of the rails. Van Depoele also constructed an exhibition road in that year, which showed no advance of any importance. Late in the same year Mr. Leo Daft constructed a locomotive to run on the Saratoga & Mt. McGregor Railroad.
During 1884 these men continued their efforts, and two new inventors put their shoulders to the wheel, which was slowly but surely gathering momentum. In July. 1884, Bentley and Knight, in Cleveland, Ohio, threw open to the public a slotted conduit road, the conduit being made of wood and placed between the rails. Their motor was hung from the car body midway between the two car axles, and was connected to the axles by means of wire cables.
A little later, in Kansas City, Mr. J. C. Henry erected the first practical overhead line in the United States. He had two trolley wires, on which ran a small carriage which made contact with the wires, and was drawn along by the car by means of a flexible copper cable.

The first electric railway at Toronto, Canada, 1885
In 1885 Mr. Daft continued his experiments, installing in Baltimore a road operated on the third - rail system. During the same year Van Depoele equipped an overhead line at Toronto, Canada, the trolley making contact on the under side of the trolley wire, as is done at the present time. For the next three years these inventors worked away in a more or less experimental way, gradually learning by disheartening failures, and by occasional successes, what methods must be abandoned and in what direction other devices must be developed and perfected.

Street Crossing of third-rail electric railway installed at Baltimore in 1885. The overhead conductor used at the crossings consisted of gas-pipe, and contact was made by a brush, mounted on a pole, similar to the present trolley pole.
Meanwhile, a new inventor. Ensign Frank J. Sprague, of the United States Navy, had come into the field. While in London, acting as a member of the jury at the Crystal Palace Exhibition at Sydenham, in 1882, he frequently rode on the Metropolitan District Underground Railway, and became impressed with the practicability of running electric trains between two planes, one being the track rails, and the other a rigid overhead rail following the centre line of all tracks and switches, connections to it to be by a trolley supported on a vertical arm having a universal movement and carried on top of the car over the centre of the trucks. However he made no application for a patent on this until nearly three years afterwards, although in 1882 he elaborated the system of main and working conductors, the latter being carried between the tracks.
In the fall of 1885 he built for experimental work on the Thirty-fourth Street branch of the New York elevated railways the first single-gear motors, centered on the axle and flexibly suspended from the truck frame. These were the originals of the modern type of electric railway motor.
The years 1887 and, more particularly, 1888, mark an important era in the development of electric railways. In the early part of 1887 Sprague took contracts in Richmond, Va., St. Joseph, Mo., and Wilmington, Del., to run cars with overhead trolleys, with nothing to show but a blue-print of a motor, the experiments on the elevated railroad at New York, considerable experience gained in the development of stationary electric motors, and belief in possibilities for the future. Curiously enough, one of the first motors used in the Durant sugar refinery in New York, where Sprague conducted his early experiments. afterwards found active service in another sugar refinery in South Boston, and in September, of 1887, in Philadelphia and New York, and in October in Boston, he operated experimental cars with storage batteries, and about the same time started an experimental car in St. Joseph. It was, however, in the year 1888 that the commercial advance was made. In that year several roads in the United States began to operate their roads and carry passengers under the practical conditions of a commercial street railway. Among the more important of these were the Sprague road at Richmond, one at Allegheny City, put in by Bentley & Knight, who had been working for a long time on the problem, and a third installed by the Thomson-Houston Company at Washington, D. C..
Sprague's technical training and his experience with stationary motors was of great service, for by means of a diligent study of the work of others and a thorough grasp of the causes of failure and of the best means of remedying defects, together with indomitable pluck, energy, and perseverance in the face of innumerable difficulties and disheartening failures, he finally succeeded in running cars carrying passengers with a promising degree of regularity. His was the first installation of an electric road on a large scale, and the natural difficulties of the route selected would be considered as offering a hard problem even in the present state of the art. There were heavy grades and many curves, some of them of very short radius, and one of the worst curves also included a heavy grade. When the first cars were run over the road. he had to station some of his men on the rear platform with instructions to get out and push when the car struck this curve,�"playing mule,'' they called it.
The lesson of this occurrence and many others of a like nature was not fully learned until driven home by many bitter experiences. This was the fact that all of the earlier inventors used motors of too small power for the work they had to do. When this lesson was learnt, there came the difficulty of designing motors of sufficient capacity, and, at the same time, small enough to get into the space available for them under the floor or the car and between the car axles. In order to make the motors small enough to get into this space and to decrease their cost and weight, it was necessary to run them at a high speed, and gear down to a lower speed at the car axle.
Various devices were used to accomplish this, such as belts, cables, cranks and connecting rods, bevel gears and others, but spur gears were finally found to be the most serviceable. Sprague hoped to use a single reduction with a pinion on the armature shaft and a large gear on the axle, but was finally forced to give up this idea because none of the manufacturing companies were, at that date, able to design a motor to run at the speed required for single reduction which would be small enough to get into the space at his disposal. He was forced, therefore, to put in an intermediate gear, into which the armature shaft pinion meshed, and which, in turn, meshed into the axle gear.
Sprague first suggested making the car truck a separate structure from the car body and proportioning this structure to bear the heavy strains brought to bear upon it by the motor. He also centered the motor frame upon the car axle by means of a sleeve cast on the motor frame and lined with a brass bushing within which the car axle could turn. This eliminated a great difficulty by keeping the centres of the gears at a constant distance from each other. It also enabled him to suspend the free end of the motor frame on springs, since thzt end could then have a certain amount of play up and down about the car axle as a centre without causing the gears to get out of mesh. The destructive pounding of the motor on the truck and on the rails was thus obviated.
While this lessened the sledge-hammer blow of the car wheels on the rails, the rails in use with the old horse cars were not heavy enough to stand the pounding that still remained, and the result was that the cars were soon running over a series of ridges like the waves of the sea, caused by the sinking of the rails between the cross-ties, and the rail joints were battered out of shape until the bumping recalled the corduroy roads of earlier days.
The motors themselves were a never- ending source of trouble, both because they were not of sufficient power and because they were not well enough protected from dust and water. There were many other minor defects as well. The heavy loads brought on motors of small power were continually resulting in burn-outs, and the necessity for running the motors below the floor of the car and very near the ground made every mud-puddle between the tracks a source of anxiety, since the commutator and the windings of the motor were not protected or incased so as to keep the water out.
Copper brushes were used on the commutator. These were necessarily set at an angle to the commutator surface, so that, if the car ran backwards for even a very short distance, the copper leaves forming the brush would be bent and crumpled up, and sparking would ensue, followed shortly by flashing over and a burnt-out motor. Even if no attempt were made to run backwards, it was impossible to prevent the slight rebound of the car on stopping when the brake was put on hard or when the car was stopped on an up grade. Every night a large number of "cripples" would come limping into the car barn, and every available man was put to work to patch them up so as to keep the road going somehow.
The power was conveyed to the motors by means of an overhead line with under-running trolley with the rails and the earth as a return. The trolley wheel was carried on a long pole, and was pressed up against the trolley wire by means of a spring on the car roof, the whole arrangement being substantially the same as the one used at the present day. Too much dependence was, however, placed on the earth as a return, and a large proportion of the energy was spent in overcoming the high resistance of the return circuit. The Bentley-Knight road at Allegheny City and the Thomson-Houston road at Washington were going through the same difficulties on a smaller scale, but they all managed to scramble along, with the aid of unceasing vigilance and energy, and kept the cars running after a fashion.
It was evident, however, to those who were in the midst of the fray that the success of electric traction was now merely a matter of perseverance in overcoming minor defects; but it was necessary, in order to procure the sinews of war, that the public should be made to share their confidence, and many were the subterfuges employed to keep from the public a knowledge of the disheartening breakdowns and the immense amount of labour and ingenuity that had to be expended in order to keep the cars running.
Sprague finally decided to risk a demonstration of the success of the system, and invited a number of officials to a ride over the road at Richmond, with the customary body guard of faithful "mules" on the rear platform, Sprague himself handling the controller. All went well for a time, and the most difficult curves and grades on the road had been negotiated carefully and gingerly without any accidents. At last the car was on a straight and level street, and Sprague put on the full current with a light heart. Suddenly there came a splutter from underneath, and The "mules" on the rear platform felt the ominous chug and drag that told of a burnt out motor.
Knowing that the machines were, as he expressed it, "red hot," Sprague, with a howling mob around who wished to see things "go," came back into the car, made some casual remark about circuits being wrong and the necessity of getting some instruments, turned out the lights and stretched himself out on a seat, while waiting for the crowd to disperse and the arrival of the "instruments,"�four powerful real mules to take the car back to the car barn.
Towards the end of the year these roads were gotten into such shape that the cars were kept going with a fair degree of regularity, and Henry M. Whitney, president of the large West End system of Boston, who was looking out for the best method of propulsion with which to replace horses, and who had almost decided on cable traction. was finally convinced of the advantages of electric traction over any other form, the Richmond road being the main factor in his conversion. As soon as it was known that this large company had decided in favour of electric traction, the public gained confidence, and electric roads began to spring up like mushrooms everywhere.
The electric railway had passed the inventive and experimental stage. The entire practicability of electric traction on street railways had been demonstrated, and it was now the turn of the engineer and designer to eliminate defects and to perfect details. There were no more radical changes or innovations, but a steady growth.
The motor problem was, perhaps, the most difficult one. The motors were increased in power and decreased in weight as designers gained experience. Carbon brushes, set radially to the commutator, were introduced by Van Depoele, so that the motor could be run backwards without injury to the brush or to the commutator. The field magnet was made up of such shape as to first partially, and finally completely, inclose the armature and the field coils, thus adequately protecting them from water, mud and dust.
By the utilisation of every available inch of space taken up by the motor, and by the use of better materials and better design, the motor was made more and more compact and its weight and cost decreased. Eventually, too, it became possible to make a motor to run at a slow enough speed for single reduction, thus dispensing with one gear.
As the motors increased in power, the truck had to be strengthened to stand the greater strains put upon it. The cars were gradually made heavier and larger, until they reached the limit of weight and length that a single truck was capable of carrying. Then came cars with two trucks, one at each end, the length of the car body being increased from 16 to 32 feet. The motors used in 1888 were rated at from 8 to 12 horse power, while now they are rated at as high as 50 horse-power and more.
The constantly increasing weights of motors, trucks and car bodies necessitated a corresponding increase in the weight of the track and in the strength and solidity of the road bed. From T or flat rails, weighing from 25 to 60 pounds per yard in 1888, the rails have been changed to girders weighing from 70 to 100 pounds per yard, and the track construction of a modern electric street railway is as strong and solid as that of a steam road.
In 1888 the earth was largely depended on as a return circuit auxiliary to the rails, but this was very unsatisfactory, both on account of the difficulty of getting the resistance low and on account of the corrosion of gas and water pipes by ihe electrolytic action caused by the current. This forced engineers to the expedient of bonding the rails, or connecting them together at the joints by short pieces of copper wire. The two lines of rails were also connected to each other at intervals, so that if a bond became loosened at any one joint,�an accident very difficult to prevent,�the current would have an alternative path back to the power station. These bonds were sometimes also reinforced by an auxiliary wire, laid parallel to the track and connected to it at intervals.
The overhead conducting system, consisting of trolley wire and feeders, while presenting its difficulties, was probably the most easily solvable part of the problem. Some difficulties were met in properly insulating and supporting the trolley wire, but these were easily overcome compared with those in the other parts of the system.
The greatest danger was from lightning, and until three or four years ago on many roads during a severe thunder storm the cars would stop running and the trolley poles would be pulled down so as to escape the danger of having the motors burnt out by lightning. The designing of efficient lightning arresters was a difficult problem, but while the protection against lightning may not be absolute even now, yet there is no longer any special danger in running the cars through the most severe thunder storm, the power station, the line and the car being all efficiently protected.
Although, in the experimental stages of electric railroading, the current was, in some cases, conveyed to .the motor by means of a trolley wire laid in a conduit under the roadbed, the overhead construction was so much cheaper and so much easier to insulate that the conduit, together with the, third-rail system, was lost sight of in the tremendous rush to fill orders for the equipment of roads using the overhead system.
The manufacturing companies, fearing that the exploitation of the more difficult and the more expensive conduit system would have a tendency to check the great demand for railway equipments, discouraged any attempts to develop it until the demand for equipments for roads using the overhead system commenced to slacken, owing to the fact that most of the street car lines had been already changed over to electric power. The companies then began to look around for new territory to conquer, and, seeing that there were several places where the overhead system was either not practicable or would not be tolerated, addressed themselves seriously to the task of developing a satisfactory conduit system.
The great difficulty was in insulating the trolley wire in a conduit under the roadbed, which was liable to be filled with water, mud or slush. This was finally obviated by making the conduit large enough to carry off the rain water or melted snow which might get into it, and by connecting it to sewers at frequent intervals. The trolley wire was supported near the top of the conduit, so that the latter had to be nearly filled before the water would reach the wire or get high enough to be thrown up against it by the trolley depending from the car. As the ordinary wooden sleepers could not be used to support the rails, cast iron yokes were made which held the conduits at their centres and the rails at their ends.
The best method of varying the speed and power of the motors also was a problem that taxed the ingenuity of the engineers. Mechanical means of doing this were suggested, but were quickly abandoned in favour of the electrical method. It was first effected by varying the resistance in series with the motor. Sprague used the commutated field method in his Richmond road, which consisted in changing the field coils from series to parallel and cutting out one of them altogether at times. This was done by means of a "controller" on the front platform operated by the motorman. For a time also an independent series-parallel switch was used; but the current had to be cut off by the main switch before changing over, and it was abandoned, partly because of slipping of wheels on heavy grades.
The problem of very effectually reducing and destroying the arc was successfully solved by Mr. Potter and others of the Thomson-Houston Company, who used Professor Thomson's method, in which he took advantage of the peculiar property which a magnet has of repelling the electric arc. He placed at the point where the circuit was broken the pole of an electro- magnet, which repelled the arc formed at that point, and thus, as it were, blew it out.
The best general results were obtained when the "closed circuit series- Parallel" controller in combination with the magnetic blow-out was designed. By means of this the two motors on a street car could be placed in series on starting and at slow speeds and changed to parallel at high speeds, thus largely reducing the loss of energy at low speeds.
The development of the central station and of the dynamos which generated the power for supplying the motors kept pace with the improvements in the other parts of the system. In 1888 the capacity of the dynamos employed was not greater than 40 kilowatts (about 50 horse-power), and they were belted to counter-shafts or to the fly-wheels of high-speed engines. As the principles of design became better known, the dynamos gradually grew in size, and the direct-connected dynamo was produced, in which the armature was mounted directly on an extension of the engine shaft. On account of the economy of space and the absence of complication that this change effected it grew rapidly in favour.
The high cost of direct-connected dynamos, due to their low speed, constituted a strong inducement to the designer to increase their size. In 1893 a 1500 kilowatt (2000 horse-power) direct-connected dynamo was exhibited at the World's Fair at Chicago, which was designed by Mr. H. F. Parshall for the General Electric Company, of New York. This was a notable achievement, since the largest direct-connected dynamo that had been previously designed was of but one-third its capacity. On account of the large size of its members, it was assembled for the first time in the power house at the Fairgrounds. It took up its load and ran without a hitch, and is still in use.
A 750-kilowatt (1000 horse-power) machine was designed at the same time, installed in the same station, and ran, just as successfully. This size was not exceeded until within the last year, when a 1600-kilowatt machine was installed, and a 2500-kilowatt (3300 horse-power) machine is now being built in the General Electric Company's shops at Schenectady, N. Y..
The great and sudden variations in the power required from a railway generator necessitated a strong and heavy construction of the moving parts of both the generator and the engine. The output of the dynamo might in a second's time go from a 50 per cent. overload down to nothing. Such variations prohibited any movement of the brushes to suit the various loads, and it was necessary to design the dynamo so that when once the brushes were set in their proper position it would not be necessary to move them to prevent sparking at any load up to the full capacity of the machine.
In the early days of electric railroading the dynamos were protected from injury from excessive currents by means of lead fuses, which would melt and thus open the circuit when the current exceeded a certain limit. These are now almost universally replaced by magnetic cut-outs, in which a magnet is made to open a switch when the current becomes too heavy. This device has the advantage of being easily adjusted to cut out at any required strength of current and of quickly closing the switch after a short-circuit or excessive overload has come upon the system.
The latest development in railway central station practice, introduced within the last two or three years, consists in what is called the multiphase system of transmission by means of alternating currents. In this system there is installed in the station an alternating current generator with step-up transformers which deliver current to the transmission lines at very high voltage. These lines are led to sub-stations at convenient points along the road where the high voltage is transformed down, and by means of rotary transformers, the alternating current is changed to a direct current, which is supplied directly to the feeders and trolley line. This high voltage on the transmission line makes it possible to place the power station at a distance from the railway, where land is low in cost, and coal and water are easily and cheaply obtained. The sub-stations can be constructed to take up very little space, and by being placed at frequent intervals along the line, effect a considerable saving of copper in the direct-current feeding system. This system also makes possible the utilisation of water power which may be available at some distance from the railway.
The street railway system at Buffalo, N. Y., furnishes an example of this method on a large scale, power from Niagara Falls being transmitted 28 miles, at 11,000 volts pressure, to Buffalo, where the voltage is transformed down, and the alternating current is fed to rotary transformers which deliver direct-current to the railway lines at 500 volts pressure.
One other system which should be mentioned here is that of self-contained accumulator or secondary battery cars. Despite the great advantage- which would result from the source of power being carried upon the car, thus making each car a separate unit, independent of the rest, engineers have not yet been able to sufficiently overcome the difficulties due to the great weight of the batteries, the fragile nature of the materials employed in their construction and the disadvantages of the handling of the liquids forming the electrolytes, to make this system practically and commercially successful as compared with the other systems now employed. A few roads are now being operated on this system, but it is doubtful whether any of them will compare in cost, convenience or reliability with the overhead or conduit systems.
A difficulty which was triumphantly met by the electric railroads and which the horse-car lines had also to contend with, has not yet been mentioned, that is, the blocking of the lines by snow. The ease with which great power could be obtained on the electric systems was strongly in their favour, and snow ploughs and snow sweepers could, at a moment's notice, be put out on the road to clear it. The rapidity with which these, machines could be made ready for work enabled the railway companies to clear the line of snow as rapidly as it fell or drifted on the tracks, so that there could be no great accumulation before removal.
The development of the high-voltage alternating-current distribution system previously mentioned has given a great impetus to the building of long suburban and interurban electric railway lines, and has made possible the utilisation of water powers at distances ranging as high as 50 miles. As methods of insulation are improved, so that higher voltages may be used. the limit of distance to which electric power may be economically transmitted will, no doubt, be greatly raised. This will result, in the near future, in the building of long lines between cities not too far apart and through thickly settled agricultural or suburban districts.
As to the adoption of electric traction on the trunk lines of large steam railway systems, it is doubtful whether this will come to pass for many years, largely because of the great expense of transmitting the power over the distances involved; but steam railways are, at present, very much alive to the possibilities of electric traction as a means of furnishing feeders to their trunk lines, and there will be a large development in this direction for a long time to come.

Reprinted from Cassier�s Magazine - Electric Railway Number, August 1899