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"I reported at the office of Mr. Edison on Fifth Avenue and told him I had seen Johnson. He looked me over and said: 'What did he promise you?'
I replied: 'Twenty-five hundred dollars a year.' He did not say much, but looked it. About that time Mr. Andrews and I came together. On July 2d of that year we were ordered to Sunbury, and to be ready to start the station on the fourth. The electrical work had to be done in forty-eight hours! Having travelled around the world, I had cultivated an indifference to any special difficulties of that kind. Mr. Andrews and I worked in collaboration until the night of the third. I think he was perhaps more appreciative than I was of the discipline of the Edison Construction Department, and thought it would be well for us to wait until the morning of the fourth before we started up. I said we were sent over to get going, and insisted on starting up on the night of the third. We had an Armington & Sims engine with sight-feed oiler. I had never seen one, and did not know how it worked, with the result that we soon burned up the babbitt metal in the bearings and spent a good part of the night getting them in order. The next day Mr. Edison, Mr. Insull, and the chief engineer of the construction department appeared on the scene and wanted to know what had happened. They found an engine somewhat loose in the bearings, and there followed remarks which would not look well in print. Andrews skipped from under; he obeyed orders; I did not. But the plant ran, and it was the first three-wire station in this country."
Seen from yet another angle, the worries of this early work were not merely those of the men on the "firing line." Mr. Insull, in speaking of this period, says: "When it was found difficult to push the central-station business owing to the lack of confidence in its financial success, Edison decided to go into the business of promoting and constructing central-station plants, and he formed what was known as the Thomas A. Edison Construction Department, which he put me in charge of. The organization was crude, the steam-engineering talent poor, and owing to the impossibility of getting any considerable capital subscribed, the plants were put in as cheaply as possible. I believe that this construction department was unkindly named the 'Destruction Department.' It served its purpose; never made any money; and I had the unpleasant task of presiding at its obsequies."
On July 4th the Sunbury plant was put into commercial operation by Edison, and he remained a week studying its conditions and watching for any unforeseen difficulty that might arise. Nothing happened, however, to interfere with the successful running of the station, and for twenty years thereafter the same two dynamos continued to furnish light in Sunbury. They were later used as reserve machines, and finally, with the engine, retired from service as part of the "Collection of Edisonia"; but they remain in practically as good condition as when installed in 1883.
Sunbury was also provided with the first electro-chemical meters used in the United States outside New York City, so that it served also to accentuate electrical practice in a most vital respect--namely, the measurement of the electrical energy supplied to customers. At this time and long after, all arc lighting was done on a "flat rate" basis. The arc lamp installed outside a customer's premises, or in a circuit for public street lighting, burned so many hours nightly, so many nights in the month; and was paid for at that rate, subject to rebate for hours when the lamp might be out through accident. The early arc lamps were rated to require 9 to 10 amperes of current, at 45 volts pressure each, receiving which they were estimated to give 2000 c.p., which was arrived at by adding together the light found at four different positions, so that in reality the actual light was about 500 c.p. Few of these data were ever actually used, however; and it was all more or less a matter of guesswork, although the central-station manager, aiming to give good service, would naturally see that the dynamos were so operated as to maintain as steadily as possible the normal potential and current. The same loose methods applied to the early attempts to use electric motors on arc-lighting circuits, and contracts were made based on the size of the motor, the width of the connecting belt, or the amount of power the customer thought he used--never on the measurement of the electrical energy furnished him.
Here again Edison laid the foundation of standard practice. It is true that even down to the present time the flat rate is applied to a great deal of incandescent lighting, each lamp being charged for individually according to its probable consumption during each month. This may answer, perhaps, in a small place where the manager can gauge pretty closely from actual observation what each customer does; but even then there are elements of risk and waste; and obviously in a large city such a method would soon be likely to result in financial disaster to the plant. Edison held that the electricity sold must be measured just like gas or water, and he proceeded to develop a meter. There was infinite scepticism around him on the subject, and while other inventors were also giving the subject their thought, the public took it for granted that anything so utterly intangible as electricity, that could not be seen or weighed, and only gave secondary evidence of itself at the exact point of use, could not be brought to accurate registration. The general att.i.tude of doubt was exemplified by the incident in Mr. J. P. Morgan's office, noted in the last chapter. Edison, however, had satisfied himself that there were various ways of accomplis.h.i.+ng the task, and had determined that the current should be measured on the premises of every consumer. His electrolytic meter was very successful, and was of widespread use in America and in Europe until the perfection of mechanical meters by Elihu Thomson and others brought that type into general acceptance. Hence the Edison electrolytic meter is no longer used, despite its excellent qualities. Houston & Kennelly in their Electricity in Everyday Life sum the matter up as follows: "The Edison chemical meter is capable of giving fair measurements of the amount of current pa.s.sing. By reason, however, of dissatisfaction caused from the inability of customers to read the indications of the meter, it has in later years, to a great extent, been replaced by registering meters that can be read by the customer."
The principle employed in the Edison electrolytic meter is that which exemplifies the power of electricity to decompose a chemical substance.
In other words it is a deposition bath, consisting of a gla.s.s cell in which two plates of chemically pure zinc are dipped in a solution of zinc sulphate. When the lights or motors in the circuit are turned on, and a certain definite small portion of the current is diverted to flow through the meter, from the positive plate to the negative plate, the latter increases in weight by receiving a deposit of metallic zinc; the positive plate meantime losing in weight by the metal thus carried away from it. This difference in weight is a very exact measure of the quant.i.ty of electricity, or number of ampere-hours, that have, so to speak, pa.s.sed through the cell, and hence of the whole consumption in the circuit. The amount thus due from the customer is ascertained by removing the cell, was.h.i.+ng and drying the plates, and weighing them in a chemical balance. a.s.sociated with this simple form of apparatus were various ingenious details and refinements to secure regularity of operation, freedom from inaccuracy, and immunity from such tampering as would permit theft of current or damage. As the freezing of the zinc sulphate solution in cold weather would check its operation, Edison introduced, for example, into the meter an incandescent lamp and a thermostat so arranged that when the temperature fell to a certain point, or rose above another point, it was cut in or out; and in this manner the meter could be kept from freezing. The standard Edison meter practice was to remove the cells once a month to the meter-room of the central-station company for examination, another set being subst.i.tuted.
The meter was cheap to manufacture and install, and not at all liable to get out of order.
In December, 1888, Mr. W. J. Jenks read an interesting paper before the American Inst.i.tute of Electrical Engineers on the six years of practical experience had up to that time with the meter, then more generally in use than any other. It appears from the paper that twenty-three Edison stations were then equipped with 5187 meters, which were relied upon for billing the monthly current consumption of 87,856 lamps and 350 motors of 1000 horse-power total. This represented about 75 per cent. of the entire lamp capacity of the stations. There was an average cost per lamp for meter operation of twenty-two cents a year, and each meter took care of an average of seventeen lamps. It is worthy of note, as to the promptness with which the Edison stations became paying properties, that four of the metered stations were earning upward of 15 per cent.
on their capital stock; three others between 8 and 10 per cent.; eight between 5 and 8 per cent.; the others having been in operation too short a time to show definite results, although they also went quickly to a dividend basis. Reports made in the discussion at the meeting by engineers showed the simplicity and success of the meter. Mr. C. L.
Edgar, of the Boston Edison system, stated that he had 800 of the meters in service cared for by two men and three boys, the latter employed in collecting the meter cells; the total cost being perhaps $2500 a year.
Mr. J. W. Lieb wrote from Milan, Italy, that he had in use on the Edison system there 360 meters ranging from 350 ampere-hours per month up to 30,000.
In this connection it should be mentioned that the a.s.sociation of Edison Illuminating Companies in the same year adopted resolutions unanimously to the effect that the Edison meter was accurate, and that its use was not expensive for stations above one thousand lights; and that the best financial results were invariably secured in a station selling current by meter. Before the same a.s.sociation, at its meeting in September, 1898, at Sault Ste. Marie, Mr. C. S. Shepard read a paper on the meter practice of the New York Edison Company, giving data as to the large number of Edison meters in use and the transition to other types, of which to-day the company has several on its circuits: "Until October, 1896, the New York Edison Company metered its current in consumer's premises exclusively by the old-style chemical meters, of which there were connected on that date 8109. It was then determined to purchase no more." Mr. Shepard went on to state that the chemical meters were gradually displaced, and that on September 1, 1898, there were on the system 5619 mechanical and 4874 chemical. The meter continued in general service during 1899, and probably up to the close of the century.
Mr. Andrews relates a rather humorous meter story of those early days: "The meter man at Sunbury was a firm and enthusiastic believer in the correctness of the Edison meter, having personally verified its reading many times by actual comparison of lamp-hours. One day, on making out a customer's bill, his confidence received a severe shock, for the meter reading showed a consumption calling for a charge of over $200, whereas he knew that the light actually used should not cost more than one-quarter of that amount. He weighed and reweighed the meter plates, and pursued every line of investigation imaginable, but all in vain. He felt he was up against it, and that perhaps another kind of a job would suit him better. Once again he went to the customer's meter to look around, when a small piece of thick wire on the floor caught his eye.
The problem was solved. He suddenly remembered that after weighing the plates he went and put them in the customer's meter; but the wire attached to one of the plates was too long to go in the meter, and he had cut it off. He picked up the piece of wire, took it to the station, weighed it carefully, and found that it accounted for about $150 worth of electricity, which was the amount of the difference."
Edison himself is, however, the best repertory of stories when it comes to the difficulties of that early period, in connection with metering the current and charging for it. He may be quoted at length as follows: "When we started the station at Pearl Street, in September, 1882, we were not very commercial. We put many customers on, but did not make out many bills. We were more interested in the technical condition of the station than in the commercial part. We had meters in which there were two bottles of liquid. To prevent these electrolytes from freezing we had in each meter a strip of metal. When it got very cold the metal would contract and close a circuit, and throw a lamp into circuit inside the meter. The heat from this lamp would prevent the liquid from freezing, so that the meter could go on doing its duty. The first cold day after starting the station, people began to come in from their offices, especially down in Front Street and Water Street, saying the meter was on fire. We received numerous telephone messages about it.
Some had poured water on it, and others said: 'Send a man right up to put it out.'
"After the station had been running several months and was technically a success, we began to look after the financial part. We started to collect some bills; but we found that our books were kept badly, and that the person in charge, who was no business man, had neglected that part of it. In fact, he did not know anything about the station, anyway.
So I got the directors to permit me to hire a man to run the station.
This was Mr. Chinnock, who was then superintendent of the Metropolitan Telephone Company of New York. I knew Chinnock to be square and of good business ability, and induced him to leave his job. I made him a personal guarantee, that if he would take hold of the station and put it on a commercial basis, and pay 5 per cent. on $600,000, I would give him $10,000 out of my own pocket. He took hold, performed the feat, and I paid him the $10,000. I might remark in this connection that years afterward I applied to the Edison Electric Light Company asking them if they would not like to pay me this money, as it was spent when I was very hard up and made the company a success, and was the foundation of their present prosperity. They said they 'were sorry'--that is, 'Wall Street sorry'--and refused to pay it. This shows what a nice, genial, generous lot of people they have over in Wall Street.
"Chinnock had a great deal of trouble getting the customers straightened out. I remember one man who had a saloon on Na.s.sau Street. He had had his lights burning for two or three months. It was in June, and Chinnock put in a bill for $20; July for $20; August about $28; September about $35. Of course the nights were getting longer. October about $40; November about $45. Then the man called Chinnock up. He said: 'I want to see you about my electric-light bill.' Chinnock went up to see him. He said: 'Are you the manager of this electric-light plant?' Chinnock said: 'I have the honor.' 'Well,' he said, my bill has gone from $20 up to $28, $35, $45. I want you to understand, young fellow, that my limit is $60.'
"After Chinnock had had all this trouble due to the incompetency of the previous superintendent, a man came in and said to him: 'Did Mr. Blank have charge of this station?' 'Yes.' 'Did he know anything about running a station like this?' Chinnock said: 'Does he KNOW anything about running a station like this? No, sir. He doesn't even suspect anything.'
"One day Chinnock came to me and said: 'I have a new customer.' I said: 'What is it?' He said: 'I have a fellow who is going to take two hundred and fifty lights.' I said: 'What for?' 'He has a place down here in a top loft, and has got two hundred and fifty barrels of "rotgut" whiskey.
He puts a light down in the barrel and lights it up, and it ages the whiskey.' I met Chinnock several weeks after, and said: 'How is the whiskey man getting along?' 'It's all right; he is paying his bill. It fixes the whiskey and takes the shudder right out of it.' Somebody went and took out a patent on this idea later.
"In the second year we put the Stock Exchange on the circuits of the station, but were very fearful that there would be a combination of heavy demand and a dark day, and that there would be an overloaded station. We had an index like a steam-gauge, called an ampere-meter, to indicate the amount of current going out. I was up at 65 Fifth Avenue one afternoon. A sudden black cloud came up, and I telephoned to Chinnock and asked him about the load. He said: 'We are up to the muzzle, and everything is running all right.' By-and-by it became so thick we could not see across the street. I telephoned again, and felt something would happen, but fortunately it did not. I said to Chinnock: 'How is it now?' He replied: 'Everything is red-hot, and the ampere-meter has made seventeen revolutions.'"
In 1883 no such fittings as "fixture insulators" were known. It was the common practice to twine the electric wires around the disused gas-fixtures, fasten them with tape or string, and connect them to lamp-sockets screwed into attachments under the gas-burners--elaborated later into what was known as the "combination fixture." As a result it was no uncommon thing to see bright sparks snapping between the chandelier and the lighting wires during a sharp thunder-storm. A startling manifestation of this kind happened at Sunbury, when the vivid display drove nervous guests of the hotel out into the street, and the providential storm led Mr. Luther Stieringer to invent the "insulating joint." This separated the two lighting systems thoroughly, went into immediate service, and is universally used to-day.
Returning to the more specific subject of pioneer plants of importance, that at Brockton must be considered for a moment, chiefly for the reason that the city was the first in the world to possess an Edison station distributing current through an underground three-wire network of conductors--the essentially modern contemporaneous practice, standard twenty-five years later. It was proposed to employ pole-line construction with overhead wires, and a party of Edison engineers drove about the town in an open barouche with a blue-print of the circuits and streets spread out on their knees, to determine how much tree-tr.i.m.m.i.n.g would be necessary. When they came to some heavily shaded spots, the fine trees were marked "T" to indicate that the work in getting through them would be "tough." Where the trees were spa.r.s.e and the foliage was thin, the same cheerful band of vandals marked the spots "E" to indicate that there it would be "easy" to run the wires. In those days public opinion was not so alive as now to the desirability of preserving shade-trees, and of enhancing the beauty of a city instead of destroying it. Brockton had a good deal of pride in its fine trees, and a strong sentiment was very soon aroused against the mutilation proposed so thoughtlessly. The investors in the enterprise were ready and anxious to meet the extra cost of putting the wires underground. Edison's own wishes were altogether for the use of the methods he had so carefully devised; and hence that bustling home of shoe manufacture was spared this infliction of more overhead wires.
The station equipment at Brockton consisted at first of three dynamos, one of which was so arranged as to supply both sides of the system during light loads by a breakdown switch connection. This arrangement interfered with correct meter registration, as the meters on one side of the system registered backward during the hours in which the combination was employed. Hence, after supplying an all-night customer whose lamps were on one side of the circuits, the company might be found to owe him some thing substantial in the morning. Soon after the station went into operation this ingenious plan was changed, and the third dynamo was replaced by two others. The Edison construction department took entire charge of the installation of the plant, and the formal opening was attended on October 1, 1883, by Mr. Edison, who then remained a week in ceaseless study and consultation over the conditions developed by this initial three-wire underground plant. Some idea of the confidence inspired by the fame of Edison at this period is shown by the fact that the first theatre ever lighted from a central station by incandescent lamps was designed this year, and opened in 1884 at Brockton with an equipment of three hundred lamps. The theatre was never piped for gas!
It was also from the Brockton central station that current was first supplied to a fire-engine house--another display of remarkably early belief in the trustworthiness of the service, under conditions where continuity of lighting was vital. The building was equipped in such a manner that the striking of the fire-alarm would light every lamp in the house automatically and liberate the horses. It was at this central station that Lieutenant Sprague began his historic work on the electric motor; and here that another distinguished engineer and inventor, Mr. H.
Ward Leonard, installed the meters and became meter man, in order that he might study in every intimate detail the improvements and refinements necessary in that branch of the industry.
The authors are indebted for these facts and some other data embodied in this book to Mr. W. J. Jenks, who as manager of this plant here made his debut in the Edison ranks. He had been connected with local telephone interests, but resigned to take active charge of this plant, imbibing quickly the traditional Edison spirit, working hard all day and sleeping in the station at night on a cot brought there for that purpose. It was a time of uninterrupted watchfulness. The difficulty of obtaining engineers in those days to run the high-speed engines (three hundred and fifty revolutions per minute) is well ill.u.s.trated by an amusing incident in the very early history of the station. A locomotive engineer had been engaged, as it was supposed he would not be afraid of anything. One evening there came a sudden flash of fire and a spluttering, sizzling noise. There had been a short-circuit on the copper mains in the station. The fireman hid behind the boiler and the engineer jumped out of the window. Mr. Sprague realized the trouble, quickly threw off the current and stopped the engine.
Mr. Jenks relates another humorous incident in connection with this plant: "One night I heard a knock at the office door, and on opening it saw two well-dressed ladies, who asked if they might be shown through.
I invited them in, taking them first to the boiler-room, where I showed them the coal-pile, explaining that this was used to generate steam in the boiler. We then went to the dynamo-room, where I pointed out the machines converting the steam-power into electricity, appearing later in the form of light in the lamps. After that they were shown the meters by which the consumption of current was measured. They appeared to be interested, and I proceeded to enter upon a comparison of coal made into gas or burned under a boiler to be converted into electricity. The ladies thanked me effusively and brought their visit to a close. As they were about to go through the door, one of them turned to me and said: 'We have enjoyed this visit very much, but there is one question we would like to ask: What is it that you make here?'"
The Brockton station was for a long time a show plant of the Edison company, and had many distinguished visitors, among them being Prof.
Elihu Thomson, who was present at the opening, and Sir W. H. Preece, of London. The engineering methods pursued formed the basis of similar installations in Lawrence, Ma.s.sachusetts, in November, 1883; in Fall River, Ma.s.sachusetts, in December, 1883; and in Newburgh, New York, the following spring.
Another important plant of this period deserves special mention, as it was the pioneer in the lighting of large s.p.a.ces by incandescent lamps.
This installation of five thousand lamps on the three-wire system was made to illuminate the buildings at the Louisville, Kentucky, Exposition in 1883, and, owing to the careful surveys, calculations, and preparations of H. M. Byllesby and the late Luther Stieringer, was completed and in operation within six weeks after the placing of the order. The Jury of Awards, in presenting four medals to the Edison company, took occasion to pay a high compliment to the efficiency of the system. It has been thought by many that the magnificent success of this plant did more to stimulate the growth of the incandescent lighting business than any other event in the history of the Edison company. It was literally the beginning of the electrical illumination of American Expositions, carried later to such splendid displays as those of the Chicago World's Fair in 1893, Buffalo in 1901, and St. Louis in 1904.
Thus the art was set going in the United States under many difficulties, but with every sign of coming triumph. Reference has already been made to the work abroad in Paris and London. The first permanent Edison station in Europe was that at Milan, Italy, for which the order was given as early as May, 1882, by an enterprising syndicate. Less than a year later, March 3, 1883, the installation was ready and was put in operation, the Theatre Santa Radegonda having been pulled down and a new central-station building erected in its place--probably the first edifice constructed in Europe for the specific purpose of incandescent lighting. Here "Jumbos" were installed from time to time, until at last there were no fewer than ten of them; and current was furnished to customers with a total of nearly ten thousand lamps connected to the mains. This pioneer system was operated continuously until February 9, 1900, or for a period of about seventeen years, when the st.u.r.dy old machines, still in excellent condition, were put out of service, so that a larger plant could be installed to meet the demand. This new plant takes high-tension polyphase current from a water-power thirty or forty miles away at Paderno, on the river Adda, flowing from the Apennines; but delivers low-tension direct current for distribution to the regular Edison three-wire system throughout Milan.
About the same time that southern Europe was thus opened up to the new system, South America came into line, and the first Edison central station there was installed at Santiago, Chile, in the summer of 1883, under the supervision of Mr. W. N. Stewart. This was the result of the success obtained with small isolated plants, leading to the formation of an Edison company. It can readily be conceived that at such an extreme distance from the source of supply of apparatus the plant was subject to many peculiar difficulties from the outset, of which Mr. Stewart speaks as follows: "I made an exhibition of the 'Jumbo' in the theatre at Santiago, and on the first evening, when it was filled with the aristocracy of the city, I discovered to my horror that the binding wire around the armature was slowly stripping off and going to pieces. We had no means of boring out the field magnets, and we cut grooves in them.
I think the machine is still running (1907). The station went into operation soon after with an equipment of eight Edison 'K' dynamos with certain conditions inimical to efficiency, but which have not hindered the splendid expansion of the local system. With those eight dynamos we had four belts between each engine and the dynamo. The steam pressure was limited to seventy-five pounds per square inch. We had two-wire underground feeders, sent without any plans or specifications for their installation. The station had neither voltmeter nor ammeter. The current pressure was regulated by a galvanometer. We were using coal costing $12 a ton, and were paid for our light in currency worth fifty cents on the dollar. The only thing I can be proud of in connection with the plant is the fact that I did not design it, that once in a while we made out to pay its operating expenses, and that occasionally we could run it for three months without a total breakdown."
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 steams.h.i.+p 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.
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 a.s.sistant 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, s.h.i.+fted 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 pa.s.sengers. 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 appears 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 s.h.i.+pped 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 pa.s.sengers--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 Was.h.i.+ngton & 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 pa.s.senger 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 b.r.e.a.s.t.s. 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, pa.s.sing 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 c.u.mbersome series of friction pulleys. Each wheel of the locomotive had a metal rim and a centre web of wood or papier-mache, and the current picked up by one set of wheels was carried through contact brushes and a bra.s.s 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.