by Jane Brox
Within, Edison's "invention factory" was peopled with blacksmiths, electricians, mechanics, machinists, model makers, a glassblower, and a mathematician. "His iron ideas, in tangled shapes, are scattered and piled everywhere; turning lathes are thickly set on the floor and the room is filled with the screech of tortured metal," one reporter wrote. "Upstairs ... is walled with shelves of bottles like an apothecary shop, thousands of bottles of all sizes and colors.... On benches and tables are batteries of all descriptions, microscopes, magnifying glasses, crucibles, retorts, an ash-covered forge, and all the apparatus of a chemist."
As the New York Herald reported, work there went on all through the night:
At six o'clock in the evening the machinists and electricians assemble in the laboratory. Edison is already present, attired in a suit of blue flannel, with hair uncombed and straggling over his eyes, a silk handkerchief around his neck, his hands and face somewhat begrimed.... The hum of machinery drowns all other sounds and each man is at his particular post. Some are drawing out curiously shaped wires so delicate that it would seem an unwary touch would demolish them. Others are vigorously filing on queer looking pieces of brass; others are adjusting little globular shaped contrivances before them. Every man seems to be engaged at something different from that occupying the attention of his fellow workman.
Edison focused a good deal of attention on the search for the best material for the filament, having concluded that the filament for the bulb had to be constructed of high-resistance material. "The more resistance your lamp offers to the passage of the current," he explained, "the more light you can obtain with a given current." In the course of many months, his crew tried and abandoned materials—carbon, platinum, silicon, boron—and then returned to carbon, which offered high resistance, although it was difficult to stabilize. They carbonized fishing line, rosewood, hickory, spruce, coconut fibers, and countless other substances. They shaped filaments as boxes, spirals, circles, horseshoes, and fanciful sprouts and curlicues, recording every experiment in a series of notebooks. To glance at even a few of the entries is to begin to comprehend the breadth and detail of their attempts:
(April 29) Wood loop cut from the thin worked holly milled by Force and cut after manner and in same former used for cardboard, carbonized by Van Cleve, were measured and put in lamps ready for pump, resistance 125 and 194 ohms.
(May 14) Carbonization. Several moulds of Bast fibers were carefully prepared and formed around wood for carbonization, but the wood proved very detrimental, every one having been broken in the moulds during the process. Van Cleve is preparing some more for trial.
(May 20) Carbonization. Van Cleve carbonized three moulds of bent wooden loops by securing the strips in slotted nickel plates; he got them out very nicely and in good shape. Bast fiber. Four of the Bast fiber lamps were measured and tested with current of 103 volts[;]they gave 30 to 32 candles and about six per horse power. They were connected to main wires in Laboratory and during the first hours three of them broke in the clamps and glass but the fiber in each instance remained in the globe unbroken. Showing the fiber to make strong carbon but difficult to form good contact with.
On October 22, 1879, Charles Batchelor, Edison's most trusted associate, placed a horseshoe-shaped filament of carbonized cotton thread in an evacuated handblown glass bulb and attached it to a series of batteries. The bulb began to glow at 1:30 A.M. and glowed through the rest of the night and the following morning. At 3:00 in the afternoon, he added more battery cells for additional power, and Batchelor noted that the bulb became as bright as three gas jets of the time, or four kerosene lamps: the brilliance of about thirty candles. An hour later, in the waning of a late-fall afternoon, the glass bulb cracked. It had burned for more than fourteen hours.
Everyone working at Menlo Park knew that all aspects of the system needed further improvement before the light would be commercially viable—the dynamo, the switches, the bulb, and the filament, for which they would eventually turn to bamboo. Still, by December Edison was able to display his system to his financial backers. At the same time, he showed it to his friend, reporter Edwin Fox, who took notes for a long article intended to be printed after the official public display of the system, which was planned for New Year's Eve. But when news leaks began appearing in other papers, Fox's newspaper, the New York Herald, decided to print a full-page story on December 21. "Edison's electric light, incredible as it may appear, is produced from a tiny strip of paper [actually carbonized thread] that a breath would blow away," wrote Fox. "Through this little strip of paper passes an electric current, and the result is a bright, beautiful light."
Upon publication of the story, thousands traveled to see Edison's invention for themselves. Wealthy New Yorkers, accustomed to the glow of gas lamps, arrived from their city in horse-drawn carriages. Others traveled by trains that steamed through the short, cold afternoons. Farmers who lived solely by the light of kerosene lamps rode in from the dark countryside, hauling wagonloads of children riding atop bales of hay. In the Menlo Park lab, they jostled one another to look at the light of the future, which would arrive for the wealthy in a handful of years. The farmers—and the farmers' children—might never live to see it in their homes, but perhaps for the moment, before its history unfolded, they were all equal in their wonder. Here was a little click that meant light was contained in a glass vacuum and need never again be linked with a flame or coaxed forth and adjusted; light that did not waver, tip, drip, stink, or consume oxygen and would not spontaneously ignite cloth dust in factories or hay in the mow. A child could be left alone with it.
Surely, a measure of its beauty and brilliance was linked to the Menlo Park setting, a place that must have been both familiar and strange: with its blacksmiths and glass blowers, but also its mathematicians and electricians, notebooks in hand. And a place remote and apart in the deep heart of winter, the time when light holds its greatest meaning. The contrast between the greater dark and the glowing "strip of paper" could only have reinforced how those present were witness to something they had never imagined, something that would change the quality of shadows as well as the quality of light, and change the atmosphere of their household nights.
The crowds continued to arrive by day and by night, so many that after a few days, Edison was forced to close his lab to them. But he kept the lamps burning so that those who came could view them from the grounds. When he opened up the laboratory again on New Year's Eve to officially display his lighting system, thousands more arrived at Menlo Park to see the twenty-five lamps in the lab, the eight in the counting room and office, the twenty on the street and in neighboring houses. The New York Herald reported:
The light was subjected to a variety of tests. Among others the inventor placed one of the electric lamps in a glass jar filled with water and turned on the current, [and] the little horseshoe filament when thus submerged burned with the same bright steady illumination as it did in the air.... Another test was turning the electric current on and off on one of the lamps with great rapidity and as many times as it was calculated the light would be turned on and off in actual house illuminations in a period of thirty years, and no perceptible variation either in the brilliancy, steadiness or durability of the lamp occurred.
By the following winter, Edison, having successfully expanded his electric system around Menlo Park by means of underground conduits, shifted his operations to Pearl Street in Manhattan, with the intention of developing a practical and workable central station that would deliver power to the surrounding neighborhood. During the several years it took him to complete the Pearl Street station, he installed incandescent lights as isolated direct current (DC) systems, first on the cruise ship Columbia and then in factories throughout the country. Manufacturers whose businesses were prone to fire, such as sugar refineries, were immediately interested in Edison's system—this light without flame or sparks—as were textile manufacturers, lithographers, and paint manufacturers. In their factories, better light would make
quality work much easier to accomplish.
A reporter who visited the Merrimack Mills in Lowell, Massachusetts, where Edison had installed a system in early 1882, described the palpable difference the light made:
Standing at one end of the room and glancing down the long rows of looms, each with its own little light placed three feet above the fabric being woven, one is first struck by the agreeable quality of the light, and next by its perfect steadiness.... The absence of heat is another valuable quality.... The temperature of the room, which would be raised ten or twelve degrees by the lighting of the gas, is not influenced by the 262 electric lights. Upon approaching the loom and examining the work in process, it appears that every thread, every line of pattern in fancy plaid goods, is remarkably clear and distinct; imperfections are quickly noticed and as quickly remedied, and it would seem that the operatives could desire no more perfect light.
Machines are most economical when they run all the time, and electric lights proved so efficient that their use extended the workday, which had been gradually losing its dependence on natural daylight since the introduction of the mechanical clock in the sixteenth century. Edison's success helped to fully establish the three-shift day and the final erasure of natural time in the factory.
A few months after Edison outfitted the Merrimack Mills, he wired the first private home for incandescent light, banker and financier J. P. Morgan's Madison Avenue brownstone. What was a boon to business was still overwhelmingly complicated for a house and—costing as much as 28 cents per kilowatt hour—only for the very wealthy. "It was a great deal of trouble to install it," recalled Morgan's son-in-law and biographer, Herbert Satterlee. "A cellar was dug underneath the stable ... and there the little steam engine and boiler for operating the generator were set up.... The gas fixtures in the house were wired, so that there was one electric light bulb substituted for a burner in each fixture. Of course there were frequent short circuits and many breakdowns on the part of the generating plant." Edison's engine, fueled by coal, belched. It was noisy. It sent up foul smoke and fumes. The neighbors complained that their houses shuddered when the boiler started up in the afternoon. It wasn't self-starting or self-maintaining. Sometimes, the house was plunged into darkness when a generator broke down or the wires short-circuited. In addition, the generator
had to be run by an expert engineer who came on duty at three P.M. and got up steam, so that any time after four o'clock on a winter's afternoon the lights could be turned on. This man went off duty at 11 P.M. It was natural that the family should often forget to watch the clock, and while visitors were still in the house, or possibly a game of cards was going on, the lights would die down and go out. If they wanted to give a party, a special arrangement had to be made to keep the engineer on duty after hours.
Morgan proved to be a patient customer: even after a renovation in which an electric cord running under the rug in his study started a fire that destroyed the room, he stood by the system. But not every wealthy client of Edison's was so intrepid or comfortable with the industrial obviousness of it. Gaslight involved no boilers or burners in the home, removed as it was from its grimy source of power by miles of pipe. The wife of railroad magnate William H. Vanderbilt refused to use the electricity in her newly wired home because she feared living over the boiler.
Meanwhile, Edison's plans for the central power station on Pearl Street in Manhattan made slow progress, in part because of the laborious task of digging subways to lay underground wires for the system. Edison insisted on buried wires, not only to follow the example of gas lines but also for one of the same reasons he favored low-voltage direct current over higher-voltage alternating current (AC): safety. In the commercial districts of Manhattan, even before the advent of electric arc streetlights in 1880, numerous small companies had strung wires for telegraphs, telephones, alarms, and stock tickers along poles down city streets. Wires sagged across avenues, weighed down top-heavy crossbars, and were tautly anchored down to the sides of buildings. Each company was responsible for the upkeep of its own lines, and not uncommonly, through neglect or storm damage, loose wires sagged or dangled from poles. Companies went out of business but failed to take down their wires, which simply deteriorated in place. The lines, at first, were problematic but not deadly, as most services ran their operations off batteries. But as historian Jill Jonnes observes,
All that changed with the coming of the new outdoor arc lighting.... The extremely high voltage alternating current required to operate these lights—as high as 3,500 volts—made their outdoor wires truly perilous. The Brush Electric Company ... built three central power stations and transmitted its high-power electricity—typically 2,000 to 3,000 volts—on wires strung among the existing low-voltage tangle. Edison wanted nothing to do with these mangled nests of live and abandoned wires.
So he worked on his subways, while a competing, unorganized lighting market grew throughout the city. Arc light companies illuminated streets, large public buildings, theaters, and hotel lobbies, while incandescent light companies built isolated systems for the interiors of buildings. Hiram Maxim, for instance, had successfully wired incandescent lights in the Mercantile Safe Deposit Company in Manhattan by late 1880. Gas companies responded to electric light by attempting to create more powerful, efficient gas lamps, an effort that would culminate in the development of the Welsbach lamp, which consisted of a burner—essentially a Bunsen burner—surrounded by a mantle composed of finely woven cotton fabric that had been impregnated with a solution of oxides and then dried. Although the burner consumed oxygen and overheated rooms just like traditional gas burners, the mantle, first advertised in 1890, glowed incandescently. It gave off impressive light, although it was also fragile. The lamp was marketed as the "electric light without the electricity."
Finally, Edison completed enough of his system by the summer of 1882 to partially light the neighborhood around Pearl Street, which included the offices of the New York Times. On September 4 of that year, he turned on his system, and those working in the newspaper office seemed particularly grateful:
It was a light that a man could sit down under and write for hours without the consciousness of having any artificial light about him.... The light was soft, mellow, and grateful to the eye, and it seemed almost like writing by daylight to have a light without a particle of flicker and with scarcely any heat to make the head ache. The electric lamps in THE TIMES Building were as thoroughly tested ... as any light could be tested in a single evening, and tested by men who have battered their eyes sufficiently by years of night work to know the good and bad points of a lamp, and the decision was unanimously in favor of the Edison electric lamp as against gas.
Those on the street at first hardly noticed the modest light. The New York Herald reported:
In the stores and business places throughout the lower quarters of the city there was a strange glow last night. The dim flicker of gas, often subdued and debilitated by grim and uncleanly globes, was supplanted by a steady glare, bright and mellow, which illuminated interiors and shone through windows fixed and unwavering. From the outer darkness these points of light looked like drops of flame suspended from jets and ready to fall at every moment. Many scurrying by in preoccupation of the moment failed to see them, but the attention of those who chanced to glance that way was at once arrested.... The test was fairly stood and the luminous horseshoes did their work well.
Direct current also did its work well in sending low voltages over short distances, but it had limitations. First, after a half mile or so, the current quickly diminished and could not be bolstered without costly outlay for thick copper wiring. Second, although direct current could adequately serve electric light customers by delivering a steady 110 volts, more powerful currents to run motors couldn't travel over the same lines. In addition to these intrinsic problems, negotiations for central stations were often complex, since many parties with differing interests would have to come to an agreement. For all of the initial success of Pearl S
treet, by the end of 1884 Edison had built only eighteen central stations (compared with hundreds of isolated systems that electrified individual homes and businesses).
The true threat to Edison's system proved to be alternating current stations, which sent high-voltage current over wires to transformers that stepped down the power to a lower voltage before delivering it to individual homes and businesses. Alternating current could accommodate different voltages, so the system could power both lights and motors, and the stations could send, via thin copper wires, a steady, strong power supply farther than the half-mile radius of direct current systems. Alternating current systems could expand outward as growth warranted.
Perhaps no one understood the advantages of alternating current more than George Westinghouse, who formed Westinghouse Electric Company in Pittsburgh in 1886 and subsequently contracted with inventor Nikola Tesla to help develop alternating current systems for his company. Tesla: tall and lean, possessing intense blue eyes, hypersensitive to the sun and to the experience of passing under a bridge, which caused pressure on his skull. "I would get a fever from looking at a peach, and if a piece of camphor was anywhere in the house, it caused me the keenest discomfort," he once said. "When a word was spoken to me, the image of the object it designated would present itself vividly to my vision and sometimes I was quite unable to distinguish whether what I saw was tangible or not." He seemed to live in a fever and quieted his mind by counting his own footsteps during his frequent walks. However much this fever might have been a burden, it was also essential to his creations. He could build machines entirely in his head, down to the smallest details, understand how they worked, and know how they needed to be improved. He could revise them without ever setting them down on paper or making a model.
