He decided that it would be wise to make the trial operation of a second "Jumbo" on a Sunday, when business houses were closed in the district, thus obviating any danger of false impressions in the public mind in the event of any extraordinary manifestations. The circumstances attending the adding of a second dynamo are thus humorously described by Edison: "My heart was in my mouth at first, but everything worked all right.... Then we started another engine and threw them in parallel. Of all the circuses since Adam was born, we had the worst then! One engine would stop, and the other would run up to about a thousand revolutions, and then they would see-saw. The trouble was with the governors. When the circus commenced, the gang that was standing around ran out precipitately, and I guess some of them kept running for a block or two. I grabbed the throttle of one engine, and E. H. Johnson, who was the only one present to keep his wits, caught hold of the other, and we shut them off." One of the "gang" that ran, but, in this case, only to the end of the room, afterward said: "At the time it was a terrifying experience, as I didn't know what was going to happen. The engines and dynamos made a horrible racket, from loud and deep groans to a hideous shriek, and the place seemed to be filled with sparks and flames of all colors. It was as if the gates of the infernal regions had been suddenly opened."
This trouble was at once attacked by Edison in his characteristic and strenuous way. The above experiment took place between three and four o'clock on a Sunday afternoon, and within a few hours he had gathered his superintendent and men of the machine-works and had them at work on a shafting device that he thought would remedy the trouble. He says: "Of course, I discovered that what had happened was that one set was running the other as a motor. I then put up a long shaft, connecting all the governors together, and thought this would certainly cure the trouble; but it didn't. The torsion of the shaft was so great that one governor still managed to get ahead of the others. Well, it was a serious state of things, and I worried over it a lot. Finally I went down to Goerck Street and got a piece of shafting and a tube in which it fitted. I twisted the shafting one way and the tube the other as far as I could, and pinned them together. In this way, by straining the whole outfit up to its elastic limit in opposite directions, the torsion was practically eliminated, and after that the governors ran together all right."
Edison realized, however, that in commercial practice this was only a temporary expedient, and that a satisfactory permanence of results could only be attained with more perfect engines that could be depended upon for close and simple regulation. The engines that were made part of the first three "Jumbos" placed in the station were the very best that could be obtained at the time, and even then had been specially designed and built for the purpose. Once more quoting Edison on this subject: "About that time" (when he was trying to run several dynamos in parallel in the Pearl Street station) "I got hold of Gardiner C. Sims, and he undertook to build an engine to run at three hundred and fifty revolutions and give one hundred and seventy-five horse-power. He went back to Providence and set to work, and brought the engine back with him to the shop. It worked only a few minutes when it busted. That man sat around that shop and slept in it for three weeks, until he got his engine right and made it work the way he wanted it to. When he reached this period I gave orders for the engine-works to run night and day until we got enough engines, and when all was ready we started the engines. Then everything worked all right.... One of these engines that Sims built ran twenty-four hours a day, three hundred and sixty-five days in the year, for over a year before it stopped." [12]
[Footnote 12: We quote the following interesting notes of
Mr. Charles L. Clarke on the question of see-sawing, or
"hunting," as it was afterward termed:
"In the Holborn Viaduct station the difficulty of 'hunting' was not experienced. At the time the 'Jumbos' were first operated in multiple arc, April 8, 1882, one machine was driven by a Porter-Allen engine, and the other by an Armington & Sims engine, and both machines were on a solid foundation. At the station at Milan, Italy, the first 'Jumbos' operated in multiple arc were driven by Porter-Allen engines, and dash-pots were applied to the governors. These machines were also upon a solid foundation, and no trouble was experienced.
"At the Pearl Street station, however, the machines were supported upon long iron floor-beams, and at the high speed of 350 revolutions per minute, considerable vertical vibration was given to the engines. And the writer is inclined to the opinion that this vibration, acting in the same direction as the action of gravitation, which was one of the two controlling forces in the operation of the Porter-Allen governor, was the primary cause of the 'hunting.' In the Armington & Sims engine the controlling forces in the operation of the governor were the centrifugal force of revolving weights, and the opposing force of compressed springs, and neither the action of gravitation nor the vertical vibrations of the engine could have any sensible effect upon the governor.">[
The Pearl Street station, as this first large plant was called, made rapid and continuous growth in its output of electric current. It started, as we have said, on September 4, 1882, supplying about four hundred lights to a comparatively small number of customers. Among those first supplied was the banking firm of Drexel, Morgan & Company, corner of Broad and Wall streets, at the outermost limits of the system. Before the end of December of the same year the light had so grown in favor that it was being supplied to over two hundred and forty customers whose buildings were wired for over five thousand lamps. By this time three more "Jumbos" had been added to the plant. The output from this time forward increased steadily up to the spring of 1884, when the demands of the station necessitated the installation of two additional "Jumbos" in the adjoining building, which, with the venous improvements that had been made in the mean time, gave the station a capacity of over eleven thousand lamps actually in service at any one time.
During the first three months of operating the Pearl Street station light was supplied to customers without charge. Edison had perfect confidence in his meters, and also in the ultimate judgment of the public as to the superiority of the incandescent electric light as against other illuminants. He realized, however, that in the beginning of the operation of an entirely novel plant there was ample opportunity for unexpected contingencies, although the greatest care had been exercised to make everything as perfect as possible. Mechanical defects or other unforeseen troubles in any part of the plant or underground system might arise and cause temporary stoppages of operation, thus giving grounds for uncertainty which would create a feeling of public distrust in the permanence of the supply of light.
As to the kind of mishap that was wont to occur, Edison tells the following story: "One afternoon, after our Pearl Street station started, a policeman rushed in and told us to send an electrician at once up to the corner of Ann and Nassau streets—some trouble. Another man and I went up. We found an immense crowd of men and boys there and in the adjoining streets—a perfect jam. There was a leak in one of our junction-boxes, and on account of the cellars extending under the street, the top soil had become insulated. Hence, by means of this leak powerful currents were passing through this thin layer of moist earth. When a horse went to pass over it he would get a very severe shock. When I arrived I saw coming along the street a ragman with a dilapidated old horse, and one of the boys told him to go over on the other side of the road—which was the place where the current leaked. When the ragman heard this he took that side at once. The moment the horse struck the electrified soil he stood straight up in the air, and then reared again; and the crowd yelled, the policeman yelled; and the horse started to run away. This continued until the crowd got so serious that the policeman had to clear it out; and we were notified to cut the current off. We got a gang of men, cut the current off for several junction-boxes, and fixed the leak. One man who had seen it came to me next day and wanted me to put in apparatus for him at a place where they sold horses. He said he could make a fortune with it, because he could get old nags in there and make them act like thoroughbreds."
So well had the work been planned and executed, however, that nothing happened to hinder the continuous working of the station and the supply of light to customers. Hence it was decided in December, 1882, to begin charging a price for the service, and, accordingly, Edison electrolytic meters were installed on the premises of each customer then connected. The first bill for lighting, based upon the reading of one of these meters, amounted to $50.40, and was collected on January 18, 1883, from the Ansonia Brass and Copper Company, 17 and 19 Cliff Street. Generally speaking, customers found that their bills compared fairly with gas bills for corresponding months where the same amount of light was used, and they paid promptly and cheerfully, with emphatic encomiums of the new light. During November, 1883, a little over one year after the station was started, bills for lighting amounting to over $9000 were collected.