we have now seen the edison lighting system given a complete, convincing demonstration in paris, london, and new york; and have noted steps taken for its introduction elsewhere on both sides of the atlantic. the paris plant, like that at the crystal palace, was a temporary exhibit. the london plant was less temporary, but not permanent, supplying before it was torn out no fewer than three thousand lamps in hotels, churches, stores, and dwellings in the vicinity of holborn viaduct. there messrs. johnson and hammer put into practice many of the ideas now standard in the art, and secured much useful data for the work in new york, of which the story has just been told.

as a matter of fact the first edison commercial station to be operated in this country was that at appleton, wisconsin, but its only serious claim to notice is that it was the initial one of the system driven by water-power. it went into service august 15, 1882, about three weeks before the pearl street station. it consisted of one small dynamo of a capacity of two hundred and eighty lights of 10 c.p. each, and was housed in an unpretentious wooden shed. the dynamo-electric machine, though small, was robust, for under all the varying speeds of water-power, and the vicissitudes of the plant to which it, belonged, it continued in active use until 1899—seventeen years.

edison was from the first deeply impressed with the possibilities of water-power, and, as this incident shows, was prompt to seize such a very early opportunity. but his attention was in reality concentrated closely on the supply of great centres of population, a task which he then felt might well occupy his lifetime; and except in regard to furnishing isolated plants he did not pursue further the development of hydro-electric stations. that was left to others, and to the application of the alternating current, which has enabled engineers to harness remote powers, and, within thoroughly economical limits, transmit thousands of horse-power as much as two hundred miles at pressures of 80,000 and 100,000 volts. owing to his insistence on low pressure, direct current for use in densely populated districts, as the only safe and truly universal, profitable way of delivering electrical energy to the consumers, edison has been frequently spoken of as an opponent of the alternating current. this does him an injustice. at the time a measure was before the virginia legislature, in 1890, to limit the permissible pressures of current so as to render it safe, he said: "you want to allow high pressure wherever the conditions are such that by no possible accident could that pressure get into the houses of the consumers; you want to give them all the latitude you can." in explaining this he added: "suppose you want to take the falls down at richmond, and want to put up a water-power? why, if we erect a station at the falls, it is a great economy to get it up to the city. by digging a cheap trench and putting in an insulated cable, and connecting such station with the central part of richmond, having the end of the cable come up into the station from the earth and there connected with motors, the power of the falls would be transmitted to these motors. if now the motors were made to run dynamos conveying low-pressure currents to the public, there is no possible way whereby this high-pressure current could get to the public." in other words, edison made the sharp fundamental distinction between high pressure alternating current for transmission and low pressure direct current for distribution; and this is exactly the practice that has been adopted in all the great cities of the country to-day. there seems no good reason for believing that it will change. it might perhaps have been altogether better for edison, from the financial standpoint, if he had not identified himself so completely with one kind of current, but that made no difference to him, as it was a matter of conviction; and edison's convictions are granitic. moreover, this controversy over the two currents, alternating and direct, which has become historical in the field of electricity—and is something like the "irrepressible conflict" we heard of years ago in national affairs—illustrates another aspect of edison's character. broad as the prairies and free in thought as the winds that sweep them, he is idiosyncratically opposed to loose and wasteful methods, to plans of empire that neglect the poor at the gate. everything he has done has been aimed at the conservation of energy, the contraction of space, the intensification of culture. burbank and his tribe represent in the vegetable world, edison in the mechanical. not only has he developed distinctly new species, but he has elucidated the intensive art of getting $1200 out of an electrical acre instead of $12—a manured market-garden inside london and a ten-bushel exhausted wheat farm outside lawrence, kansas, being the antipodes of productivity—yet very far short of exemplifying the difference of electrical yield between an acre of territory in edison's "first new york district" and an acre in some small town.

edison's lighting work furnished an excellent basis—in fact, the only one—for the development of the alternating current now so generally employed in central-station work in america; and in the mcgraw electrical directory of april, 1909, no fewer than 4164 stations out of 5780 reported its use. when the alternating current was introduced for practical purposes it was not needed for arc lighting, the circuit for which, from a single dynamo, would often be twenty or thirty miles in length, its current having a pressure of not less than five or six thousand volts. for some years it was not found feasible to operate motors on alternating-current circuits, and that reason was often urged against it seriously. it could not be used for electroplating or deposition, nor could it charge storage batteries, all of which are easily within the ability of the direct current. but when it came to be a question of lighting a scattered suburb, a group of dwellings on the outskirts, a remote country residence or a farm-house, the alternating current, in all elements save its danger, was and is ideal. its thin wires can be carried cheaply over vast areas, and at each local point of consumption the transformer of size exactly proportioned to its local task takes the high-voltage transmission current and lowers its potential at a ratio of 20 or 40 to 1, for use in distribution and consumption circuits. this evolution has been quite distinct, with its own inventors like gaulard and gibbs and stanley, but came subsequent to the work of supplying small, dense areas of population; the art thus growing from within, and using each new gain as a means for further achievement.

nor was the effect of such great advances as those made by edison limited to the electrical field. every department of mechanics was stimulated and benefited to an extraordinary degree. copper for the circuits was more highly refined than ever before to secure the best conductivity, and purity was insisted on in every kind of insulation. edison was intolerant of sham and shoddy, and nothing would satisfy him that could not stand cross-examination by microscope, test-tube, and galvanometer. it was, perhaps, the steam-engine on which the deepest imprint for good was made, referred to already in the remarks of mr. f. j. sprague in the preceding chapter, but best illustrated in the perfection of the modern high-speed engine of the armington & sims type. unless he could secure an engine of smoother running and more exactly governed and regulated than those available for his dynamo and lamp, edison realized that he would find it almost impossible to give a steady light. he did not want his customers to count the heart-beats of the engine in the flicker of the lamp. not a single engine was even within gunshot of the standard thus set up, but the emergency called forth its man in gardiner c. sims, a talented draughtsman and designer who had been engaged in locomotive construction and in the engineering department of the united states navy. he may be quoted as to what happened: "the deep interest, financial and moral, and friendly backing i received from mr. edison, together with valuable suggestions, enabled me to bring out the engine; as i was quite alone in the world—poor—i had found a friend who knew what he wanted and explained it clearly. mr. edison was a leader far ahead of the time. he compelled the design of the successful engine.

"our first engine compelled the inventing and making of a suitable engine indicator to indicate it—the tabor. he obtained the desired speed and load with a friction brake; also regulator of speed; but waited for an indicator to verify it. then again there was no known way to lubricate an engine for continuous running, and mr. edison informed me that as a marine engine started before the ship left new york and continued running until it reached its home port, so an engine for his purposes must produce light at all times. that was a poser to me, for a five-hours' run was about all that had been required up to that time.

"a day or two later mr. edison inquired: 'how far is it from here to lawrence; it is a long walk, isn't it?' 'yes, rather.' he said: 'of course you will understand i meant without oil.' to say i was deeply perplexed does not express my feelings. we were at the machine works, goerck street. i started for the oil-room, when, about entering, i saw a small funnel lying on the floor. it had been stepped on and flattened. i took it up, and it had solved the engine-oiling problem—and my walk to lawrence like a tramp actor's was off! the eccentric strap had a round glass oil-cup with a brass base that screwed into the strap. i took it off, and making a sketch, went to dave cunningham, having the funnel in my hand to illustrate what i wanted made. i requested him to make a sheet-brass oil-cup and solder it to the base i had. he did so. i then had a standard made to hold another oil-cup, so as to see and regulate the drop-feed. on this combination i obtained a patent which is now universally used."

it is needless to say that in due course the engine builders of the united states developed a variety of excellent prime movers for electric-light and power plants, and were grateful to the art from which such a stimulus came to their industry; but for many years one never saw an edison installation without expecting to find one or more armington & sims high-speed engines part of it. though the type has gone out of existence, like so many other things that are useful in their day and generation, it was once a very vital part of the art, and one more illustration of that intimate manner in which the advances in different fields of progress interact and co-operate.

edison had installed his historic first great central-station system in new york on the multiple arc system covered by his feeder and main invention, which resulted in a notable saving in the cost of conductors as against a straight two-wire system throughout of the "tree" kind. he soon foresaw that still greater economy would be necessary for commercial success not alone for the larger territory opening, but for the compact districts of large cities. being firmly convinced that there was a way out, he pushed aside a mass of other work, and settled down to this problem, with the result that on november 20, 1882, only two months after current had been sent out from pearl street, he executed an application for a patent covering what is now known as the "three-wire system." it has been universally recognized as one of the most valuable inventions in the history of the lighting art. [13] its use resulted in a saving of over 60 per cent. of copper in conductors, figured on the most favorable basis previously known, inclusive of those calculated under his own feeder and main system. such economy of outlay being effected in one of the heaviest items of expense in central-station construction, it was now made possible to establish plants in towns where the large investment would otherwise have been quite prohibitive. the invention is in universal use today, alike for direct and for alternating current, and as well in the equipment of large buildings as in the distribution system of the most extensive central-station networks. one cannot imagine the art without it.

[footnote 13: for technical description and illustration of

this invention, see appendix.]

the strong position held by the edison system, under the strenuous competition that was already springing up, was enormously improved by the introduction of the three-wire system; and it gave an immediate impetus to incandescent lighting. desiring to put this new system into practical use promptly, and receiving applications for licenses from all over the country, edison selected brockton, massachusetts, and sunbury, pennsylvania, as the two towns for the trial. of these two brockton required the larger plant, but with the conductors placed underground. it was the first to complete its arrangements and close its contract. mr. henry villard, it will be remembered, had married the daughter of garrison, the famous abolitionist, and it was through his relationship with the garrison family that brockton came to have the honor of exemplifying so soon the principles of an entirely new art. sunbury, however, was a much smaller installation, employed overhead conductors, and hence was the first to "cross the tape." it was specially suited for a trial plant also, in the early days when a yield of six or eight lamps to the horse-power was considered subject for congratulation. the town being situated in the coal region of pennsylvania, good coal could then be obtained there at seventy-five cents a ton.

the sunbury generating plant consisted of an armington & sims engine driving two small edison dynamos having a total capacity of about four hundred lamps of 16 c.p. the indicating instruments were of the crudest construction, consisting of two voltmeters connected by "pressure wires" to the centre of electrical distribution. one ammeter, for measuring the quantity of current output, was interpolated in the "neutral bus" or third-wire return circuit to indicate when the load on the two machines was out of balance. the circuits were opened and closed by means of about half a dozen roughly made plug-switches. [14] the "bus-bars" to receive the current from the dynamos were made of no. 000 copper line wire, straightened out and fastened to the wooden sheathing of the station by iron staples without any presence to insulation. commenting upon this mr. w. s. andrews, detailed from the central staff, says: "the interior winding of the sunbury station, including the running of two three-wire feeders the entire length of the building from back to front, the wiring up of the dynamos and switchboard and all instruments, together with bus-bars, etc.—in fact, all labor and material used in the electrical wiring installation—amounted to the sum of $90. i received a rather sharp letter from the new york office expostulating for this extravagant expenditure, and stating that great economy must be observed in future!" the street conductors were of the overhead pole-line construction, and were installed by the construction company that had been organized by edison to build and equip central stations. a special type of street pole had been devised by him for the three-wire system.

[footnote 14: 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.]

supplementing the story of mr. andrews is that of lieut. f. j. sprague, who also gives a curious glimpse of the glorious uncertainties and vicissitudes of that formative period. mr. sprague served on the jury at the crystal palace exhibition with darwin's son—the present sir horace—and after the tests were ended left the navy and entered edison's service at the suggestion of mr. e. h. johnson, who was edison's shrewd recruiting sergeant in those days: "i resigned sooner than johnson expected, and he had me on his hands. meanwhile he had called upon me to make a report of the three-wire system, known in england as the hopkinson, both dr. john hopkinson and mr. edison being independent inventors at practically the same time. i reported on that, left london, and landed in new york on the day of the opening of the brooklyn bridge in 1883—may 24—with a year's leave of absence.

"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 attitude 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 accomplishing 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 passing. 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 glass 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 quantity of electricity, or number of ampere-hours, that have, so to speak, passed 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, washing and drying the plates, and weighing them in a chemical balance. associated 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 substituted. 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 institute 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 association 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 association, 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 nassau 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-trimming 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 sparse 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 illustrated 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, massachusetts, in november, 1883; in fall river, massachusetts, 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 spaces 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 sturdy 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 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.