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Edison, His Life and Inventions, vol. 1

Page 37

by Frank Lewis Dyer


  It was not until 1885 that the first Edison station in Germany was established; but the art was still very young, and the plant represented pioneer lighting practice in the Empire. The station at Berlin comprised five boilers, and six vertical steam-engines driving by belts twelve Edison dynamos, each of about fifty-five horse-power capacity. A model of this station is preserved in the Deutschen Museum at Munich. In the bulletin of the Berlin Electricity Works for May, 1908, it is said with regard to the events that led up to the creation of the system, as noted already at the Rathenau celebration: ``The year 1881 was a mile-stone in the history of the Allgemeine Elektricitaets Gesellschaft. The International Electrical Exposition at Paris was intended to place before the eyes of the civilized world the achievements of the century. Among the exhibits of that Exposition was the Edison system of incandescent lighting. It became the basis of modern heavy current technics.'' The last phrase is italicized as being a happy and authoritative description, as well as a tribute.

  This chapter would not be complete if it failed to include some reference to a few of the earlier isolated plants of a historic character. Note has already been made of the first Edison plants afloat on the Jeannette and Columbia, and the first commercial plant in the New York lithographic establishment. The first mill plant was placed in the woollen factory of James Harrison at Newburgh, New York, about September 15, 1881. A year later, Mr. Harrison wrote with some pride: ``I believe my mill was the first lighted with your electric light, and therefore may be called No. 1. Besides being job No. 1 it is a No. 1 job, and a No. 1 light, being better and cheaper than gas and absolutely safe as to fire.'' The first steam-yacht lighted by incandescent lamps was James Gordon Bennett's Namouna, equipped early in 1882 with a plant for one hundred and twenty lamps of eight candlepower, which remained in use there many years afterward.

  The first Edison plant in a hotel was started in October, 1881, at the Blue Mountain House in the Adirondacks, and consisted of two ``Z'' dynamos with a complement of eight and sixteen candle lamps. The hotel is situated at an elevation of thirty-five hundred feet above the sea, and was at that time forty miles from the railroad. The machinery was taken up in pieces on the backs of mules from the foot of the mountain. The boilers were fired by wood, as the economical transportation of coal was a physical impossibility. For a six-hour run of the plant one-quarter of a cord of wood was required, at a cost of twenty-five cents per cord.

  The first theatre in the United States to be lighted by an Edison isolated plant was the Bijou Theatre, Boston. The installation of boilers, engines, dynamos, wiring, switches, fixtures, three stage regulators, and six hundred and fifty lamps, was completed in eleven days after receipt of the order, and the plant was successfully operated at the opening of the theatre, on December 12, 1882.

  The first plant to be placed on a United States steamship was the one consisting of an Edison ``Z'' dynamo and one hundred and twenty eight-candle lamps installed on the Fish Commission's steamer Albatross in 1883. The most interesting feature of this installation was the employment of special deep-sea lamps, supplied with current through a cable nine hundred and forty feet in length, for the purpose of alluring fish. By means of the brilliancy of the lamps marine animals in the lower depths were attracted and then easily ensnared.

  [17.1] For technical description and illustration of this invention, see Appendix. [17.2] By reason of the experience gained at this station through the use of these crude plug-switches, Mr. Edison started a competition among a few of his assistants to devise something better. The result was the invention of a ``breakdown'' switch by Mr. W. S. Andrews, which was accepted by Mr. Edison as the best of the devices suggested, and was developed and used for a great many years afterward.

  CHAPTER XVIII

  THE ELECTRIC RAILWAY

  EDISON had no sooner designed his dynamo in 1879 than he adopted the same form of machine for use as a motor. The two are shown in the Scientific American of October 18, 1879, and are alike, except that the dynamo is vertical and the motor lies in a horizontal position, the article remarking: ``Its construction differs but slightly from the electric generator.'' This was but an evidence of his early appreciation of the importance of electricity as a motive power; but it will probably surprise many people to know that he was the inventor of an electric motor before he perfected his incandescent lamp. His interest in the subject went back to his connection with General Lefferts in the days of the evolution of the stock ticker. While Edison was carrying on his shop at Newark, New Jersey, there was considerable excitement in electrical circles over the Payne motor, in regard to the alleged performance of which Governor Cornell of New York and other wealthy capitalists were quite enthusiastic. Payne had a shop in Newark, and in one small room was the motor, weighing perhaps six hundred pounds. It was of circular form, incased in iron, with the ends of several small magnets sticking through the floor. A pulley and belt, connected to a circular saw larger than the motor, permitted large logs of oak timber to be sawed with ease with the use of two small cells of battery. Edison's friend, General Lefferts, had become excited and was determined to invest a large sum of money in the motor company, but knowing Edison's intimate familiarity with all electrical subjects he was wise enough to ask his young expert to go and see the motor with him. At an appointed hour Edison went to the office of the motor company and found there the venerable Professor Morse, Governor Cornell, General Lefferts, and many others who had been invited to witness a performance of the motor. They all proceeded to the room where the motor was at work. Payne put a wire in the binding-post of the battery, the motor started, and an assistant began sawing a heavy oak log. It worked beautifully, and so great was the power developed, apparently, from the small battery, that Morse exclaimed: ``I am thankful that I have lived to see this day.'' But Edison kept a close watch on the motor. The results were so foreign to his experience that he knew there was a trick in it. He soon discovered it. While holding his hand on the frame of the motor he noticed a tremble coincident with the exhaust of an engine across the alleyway, and he then knew that the power came from the engine by a belt under the floor, shifted on and off by a magnet, the other magnets being a blind. He whispered to the General to put his hand on the frame of the motor, watch the exhaust, and note the coincident tremor. The General did so, and in about fifteen seconds he said: ``Well, Edison, I must go now. This thing is a fraud.'' And thus he saved his money, although others not so shrewdly advised were easily persuaded to invest by such a demonstration.

  A few years later, in 1878, Edison went to Wyoming with a group of astronomers, to test his tasimeter during an eclipse of the sun, and saw the land white to harvest. He noticed the long hauls to market or elevator that the farmers had to make with their loads of grain at great expense, and conceived the idea that as ordinary steam-railroad service was too costly, light electric railways might be constructed that could be operated automatically over simple tracks, the propelling motors being controlled at various points. Cheap to build and cheap to maintain, such roads would be a great boon to the newer farming regions of the West, where the highways were still of the crudest character, and where transportation was the gravest difficulty with which the settlers had to contend. The plan seems to have haunted him, and he had no sooner worked out a generator and motor that owing to their low internal resistance could be operated efficiently, than he turned his hand to the practical trial of such a railroad, applicable to both the haulage of freight and the transportation of passengers. Early in 1880, when the tremendous rush of work involved in the invention of the incandescent lamp intermitted a little, he began the construction of a stretch of track close to the Menlo Park laboratory, and at the same time built an electric locomotive to operate over it.

  This is a fitting stage at which to review briefly what had been done in electric traction up to that date. There was absolutely no art, but there had been a number of sporadic and very interesting experiments made. The honor of the first attempt of any kind appear
s to rest with this country and with Thomas Davenport, a self-trained blacksmith, of Brandon, Vermont, who made a small model of a circular electric railway and cars in 1834, and exhibited it the following year in Springfield, Boston, and other cities. Of course he depended upon batteries for current, but the fundamental idea was embodied of using the track for the circuit, one rail being positive and the other negative, and the motor being placed across or between them in multiple arc to receive the current. Such are also practically the methods of to-day. The little model was in good preservation up to the year 1900, when, being shipped to the Paris Exposition, it was lost, the steamer that carried it foundering in mid-ocean. The very broad patent taken out by this simple mechanic, so far ahead of his times, was the first one issued in America for an electric motor. Davenport was also the first man to apply electric power to the printing-press, in 1840. In his traction work he had a close second in Robert Davidson, of Aberdeen, Scotland, who in 1839 operated both a lathe and a small locomotive with the motor he had invented. His was the credit of first actually carrying passengers--two at a time, over a rough plank road--while it is said that his was the first motor to be tried on real tracks, those of the Edinburgh-Glasgow road, making a speed of four miles an hour.

  The curse of this work and of all that succeeded it for a score of years was the necessity of depending upon chemical batteries for current, the machine usually being self-contained and hauling the batteries along with itself, as in the case of the famous Page experiments in April, 1851, when a speed of nineteen miles an hour was attained on the line of the Washington & Baltimore road. To this unfruitful period belonged, however, the crude idea of taking the current from a stationary source of power by means of an overhead contact, which has found its practical evolution in the modern ubiquitous trolley; although the patent for this, based on his caveat of 1879, was granted several years later than that to Stephen D. Field, for the combination of an electric motor operated by means of a current from a stationary dynamo or source of electricity conducted through the rails. As a matter of fact, in 1856 and again in 1875, George F. Green, a jobbing machinist, of Kalamazoo, Michigan, built small cars and tracks to which current was fed from a distant battery, enough energy being utilized to haul one hundred pounds of freight or one passenger up and down a ``road'' two hundred feet long. All the work prior to the development of the dynamo as a source of current was sporadic and spasmodic, and cannot be said to have left any trace on the art, though it offered many suggestions as to operative methods.

  The close of the same decade of the nineteenth century that saw the electric light brought to perfection, saw also the realization in practice of all the hopes of fifty years as to electric traction. Both utilizations depended upon the supply of current now cheaply obtainable from the dynamo. These arts were indeed twins, feeding at inexhaustible breasts. In 1879, at the Berlin Exhibition, the distinguished firm of Siemens, to whose ingenuity and enterprise electrical development owes so much, installed a road about one-third of a mile in length, over which the locomotive hauled a train of three small cars at a speed of about eight miles an hour, carrying some twenty persons every trip. Current was fed from a dynamo to the motor through a central third rail, the two outer rails being joined together as the negative or return circuit. Primitive but essentially successful, this little road made a profound impression on the minds of many inventors and engineers, and marked the real beginning of the great new era, which has already seen electricity applied to the operation of main lines of trunk railways. But it is not to be supposed that on the part of the public there was any great amount of faith then discernible; and for some years the pioneers had great difficulty, especially in this country, in raising money for their early modest experiments. Of the general conditions at this moment Frank J. Sprague says in an article in the Century Magazine of July, 1905, on the creation of the new art: ``Edison was perhaps nearer the verge of great electric-railway possibilities than any other American. In the face of much adverse criticism he had developed the essentials of the low-internal-resistance dynamo with high-resistance field, and many of the essential features of multiple-arc distribution, and in 1880 he built a small road at his laboratory at Menlo Park.''

  On May 13th of the year named this interesting road went into operation as the result of hard and hurried work of preparation during the spring months. The first track was about a third of a mile in length, starting from the shops, following a country road, passing around a hill at the rear and curving home, in the general form of the letter ``U.'' The rails were very light. Charles T. Hughes, who went with Edison in 1879, and was in charge of much of the work, states that they were ``second'' street-car rails, insulated with tar canvas paper and things of that sort-- ``asphalt.'' They were spiked down on ordinary sleepers laid upon the natural grade, and the gauge was about three feet six inches. At one point the grade dropped some sixty feet in a distance of three hundred, and the curves were of recklessly short radius. The dynamos supplying current to the road were originally two of the standard size ``Z'' machines then being made at the laboratory, popularly known throughout the Edison ranks as ``Longwaisted Mary Anns,'' and the circuits from these were carried out to the rails by underground conductors. They were not large--about twelve horse-power each--generating seventy-five amperes of current at one hundred and ten volts, so that not quite twenty-five horse-power of electrical energy was available for propulsion.

  The locomotive built while the roadbed was getting ready was a four-wheeled iron truck, an ordinary flat dump-car about six feet long and four feet wide, upon which was mounted a ``Z'' dynamo used as a motor, so that it had a capacity of about twelve horsepower. This machine was laid on its side, with the armature end coming out at the front of the locomotive, and the motive power was applied to the driving-axle by a cumbersome series of friction pulleys. Each wheel of the locomotive had a metal rim and a centre web of wood or papier-mâché, and the current picked up by one set of wheels was carried through contact brushes and a brass hub to the motor; the circuit back to the track, or other rail, being closed through the other wheels in a similar manner. The motor had its field-magnet circuit in permanent connection as a shunt across the rails, protected by a crude bare copper-wire safety-catch. A switch in the armature circuit enabled the motorman to reverse the direction of travel by reversing the current flow through the armature coils.

  Things went fairly well for a time on that memorable Thursday afternoon, when all the laboratory force made high holiday and scrambled for foothold on the locomotive for a trip; but the friction gearing was not equal to the sudden strain put upon it during one run and went to pieces. Some years later, also, Daft again tried friction gear in his historical experiments on the Manhattan Elevated road, but the results were attended with no greater success. The next resort of Edison was to belts, the armature shafting belted to a countershaft on the locomotive frame, and the countershaft belted to a pulley on the car-axle. The lever which threw the former friction gear into adjustment was made to operate an idler pulley for tightening the axle-belt. When the motor was started, the armature was brought up to full revolution and then the belt was tightened on the car-axle, compelling motion of the locomotive. But the belts were liable to slip a great deal in the process, and the chafing of the belts charred them badly. If that did not happen, and if the belt was made taut suddenly, the armature burned out--which it did with disconcerting frequency. The next step was to use a number of resistance-boxes in series with the armature, so that the locomotive could start with those in circuit, and then the motorman could bring it up to speed gradually by cutting one box out after the other. To stop the locomotive, the armature circuit was opened by the main switch, stopping the flow of current, and then brakes were applied by long levers. Matters generally and the motors in particular went much better, even if the locomotive was so freely festooned with resistance-boxes all of perceptible weight and occupying much of the limited space. These details show forcibly and typically the painf
ul steps of advance that every inventor in this new field had to make in the effort to reach not alone commercial practicability, but mechanical feasibility. It was all empirical enough; but that was the only way open even to the highest talent.

  Smugglers landing laces and silks have been known to wind them around their bodies, as being less ostentatious than carrying them in a trunk. Edison thought his resistance-boxes an equally superfluous display, and therefore ingeniously wound some copper resistance wire around one of the legs of the motor field magnet, where it was out of the way, served as a useful extra field coil in starting up the motor, and dismissed most of the boxes back to the laboratory; a few being retained under the seat for chance emergencies. Like the boxes, this coil was in series with the armature, and subject to plugging in and out at will by the motorman. Thus equipped, the locomotive was found quite satisfactory, and long did yeoman service. It was given three cars to pull, one an open awning-car with two park benches placed back to back; one a flat freight-car, and one box-car dubbed the ``Pullman,'' with which Edison illustrated a system of electric braking. Although work had been begun so early in the year, and the road had been operating since May, it was not until July that Edison executed any application for patents on his ``electromagnetic railway engine,'' or his ingenious braking system. Every inventor knows how largely his fate lies in the hands of a competent and alert patent attorney, in both the preparation and the prosecution of his case; and Mr. Sprague is justified in observing in his Century article: ````The paucity of controlling claims obtained in these early patents is remarkable.'' It is notorious that Edison did not then enjoy the skilful aid in safeguarding his ideas that he commanded later.

 

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