So, steam power had by the last third of the nineteenth century wrought revolutions in mining, manufacturing, and transportation on land, the rivers, and the oceans. That would seem to be enough. But the inventors of the nineteenth century would wrest yet one more revolution from steam, by generating from it electric light, and then electric power.
The dream of electric power began in the 1830s. A fever for electricity and its marvels swept Europe in response to the discoveries and demonstrations of the likes of William Sturgeon and Michael Faraday. The electric battery had existed already for decades; it could amuse and amaze, but had not found much practical use. The appearance of electromagnets and electric motors promised to change all that, by converting the electrical power of the battery cell into mechanical work. Enthusiasts painted a phantasmagorical picture of a coming electric age that would supplant belching steam power with the quiet whirr of electricity.[1] Nicholas Callan, an Irish professor of natural philosophy and regular contributor to Sturgeon’s Annals of Electricity, argued that with zinc batteries and electromagnetic engines,
…an electro-magnetic engine as powerful as any of the steam engines on the Kingstown Railway, may be constructed for the sum of £250 ; secondly, that the weight of such an engine will not exceed two tons ; thirdly, that the annual expense of working and repairing it will not be more than £300. If my calculations be correct, the expense of propelling the railway carriages by electro-magnetism, will be scarcely one fourth of the cost of steam.[2]
James Joule, later famous for as one of England’s most prominent physicists, but employed at the time as the manager of his family’s brewery, initially shared these enthusiasms. He wrote in 1839,
I can hardly doubt that electro-magnetism will ultimately be substituted for steam to propel machinery. If the power of the engine is in proportion to the attractive force of its magnets, and if this attraction is as the square of the electric force, the economy will be in the direct ratio of the quantity of electricity, and the cost of working the engine may be reduced ad infinitum.[3]
Yet it fell to Joule himself to burst this bubble decisively with the sharp tools he and his contemporaries had developed within the newly burgeoning science of energy. By realizing that in making electric power a battery must consume some metal, and measuring the amount of work that could be produced a given amount of that metal (typically zinc at the time), it was possible to show decisively that the batteries of the time could never supplant coal. A given mass of zinc generated less work than the same mass of coal, despite costing twenty times more.[4]
There still remained, however, the possibility that the electric circuit could do something wholly new, that had no steam-powered equivalent. The first such application to come to light was electro-plating, the use of an electric current to induce a metal in solution (such as gold or silver) to coat another metal object. The Italian chemist Luigi Brugnatelli was the first to demonstrate that this could be done, but the technique did not become widely known and used until the end of the 1830s. The second was electric light.
Arc
In 1808, Humphrey Davy—poet, philosopher, inventor, and showman—then at the height of his fame as a public lecturer at the Royal Institution, gave a lecture in which he demonstrated the power of electricity to create a bright and persistent light:
When small pieces of charcoal from the willow, that had been intensely ignited, were acted upon by Voltaic electricity in a Torricellian vacuum… from the charcoal a flame seemed to issue of a most brilliant purple, and formed, as it were, a conducting chain of light of nearly an inch in length…[5]
The flow of electricity created a glowing arc as it leapt the gap between the two pieces of charcoal. A year later he repeated the experiment in air, not a vacuum, with a battery four times larger (consisting of 2,000 cells). According to one observer, “[t]he spark, the light of which was so intense as to resemble that of the sun, struck through some lines of air, and produced a discharge through heated -air of nearly three inches in length, and of a dazzling splendour.”[6]
The phenomenon made for a brilliant demonstration; Davy’s audiences, eager for sensible displays of the power of science, loved this kind of electrical parlor trick. But no one thought of it as a practical form of artificial light. The battery drew down its charge quickly and the charcoal burned itself away under the heat of the arc. Soon enough, between the weakening current and the shrinking charcoal, the gap grew too large to be bridged by the current, and the arc failed. Even were that not the case, a battery with hundreds or thousands of cells, each with its own four-inch-square metal plates, was far too costly for everyday use.
Real progress towards electric light did not begin until the 1840s. Inventors in France and Britain developed lamps with hard coke rods that burned more slowly and evenly than charcoal, and regulator mechanisms using an electromagnet to force the rods closer together whenever the current weakened, maintaining the correct gap. With these features, as well as improved battery cells, arc lights could burn continuously for hours, and found use as novelty lighting for hotel lobbies and theater special effects; the rising sun for the opera “Le Prophète,” for example.[7]
Other inventors developed still better regulators in the 1850s, but the expense and short life of the batteries remained as insurmountable barriers to wider use.
Dynamo
The answer lay with steam power. Far from striking down coal and inaugurating a new era of clean energy, electric power would become successful only by partnering with steam. The fact that motion could create an electric charge had been known for millennia. The very concept of electricity was named after amber (elektron in Greek), because that material would attract objects after being rubbed. But to create a machine that could efficiently transform the motion of a steam engine into a usable current, an effective generator, was another matter.
In 1820, Hans Oersted showed that an electric current could create mechanical force via a magnet. In the early 1830s, Michael Faraday then showed the reverse; that a magnet could induce a current. His generator, consisting of a metal disk spinning between the arms of a magnet, produced a weak current across the disk, capable of little more than making the needle of a galvanometer jump. Similar generators, called magnetos, went through years of incremental improvements over the next twenty years, without seeing much use outside the laboratory, except for a few sold to the electroplating industry. But they did demonstrate that rotary motion (such as from a steam engine) could be used to generate a current.[8]
In the mid-1850s, Frederick Holmes, a London chemistry professor, constructed a magneto with an armature of six disks each mounted with coils of wire on its perimeter that spun between seven banks of magnets, and showed that it could power an arc lamp. Holmes believed that his new device could replace oil lamps in England’s lighthouses, and petitioned Trinity House, the organization responsible for the oversight of the houses, to try it out. With the encouragement of Faraday, their scientific advisor, the Elder Brethren of that house agreed to trial an arc light powered by a magneto of Holmes’ design weighing more than five tons, which was driven in turn by a three-horsepower steam engine. The expensive, bulky, and sometimes balky apparatus did not take the lighthouse world by storm, but it provided the first glimpse of the potential for a fruitful union between steam and electricity.[9]
In France, a company formed to develop arc lighting, the Société l’Alliance, made further advances. A researcher at the Conservatoire National des Arts et Métiers discovered through experimentation that the magneto wasted much of its output in sparks from the commutator (typically a metal brush) that converted the alternating current of the spinning magneto into the familiar unidirectional current of a battery-powered circuit. By removing the commutator to make an alternating current generator, Alliance achieved much greater efficiency and had more success in selling their instruments to French lighthouses than Holmes had to British ones. An Alliance arc light shone forth from Port Said at the Mediterranean entrance of the Suez Canal when it opened in 1869.[10]
But the true leap forward for practical arc lighting—and practical electric power more generally—came with the self-exciting dynamo, created independently in 1866 by Charles Wheatstone and Samuel Varley in England and Werner von Siemens in Berlin. Up to this point, magnetos had spun their moving element within the field of one or more permanent magnets to induce a current. But the dynamo used permanent magnets only as a pilot light to ignite much more powerful electromagnets: it diverted some of the current generated by the spinning armature to electromagnetic coils in the surrounding stator, which in turn induced a far stronger current in the main circuit. Tests by England’s Trinity House in the 1870s showed that a Siemens dynamo weighed almost thirty times less than a Holmes magneto, while producing four times as much light per horsepower.[11]
System
Two obstacles still stood in the way of the widespread use of arc lighting. First, because they relied on an electromagnet wired into the circuit to regulating the spacing of the arc, only one lamp could be placed in the circuit from one generator; otherwise, variations in the current caused by one lamp would disrupt the control mechanisms on the others. Second, the lights simply didn’t last long enough; they could not last an entire night without shutting off the circuit to replace the carbons. Pavel Yablochkov, a retired Russian Army engineer living in Paris, solved the first of these problems with his “candles.” Rather than placing the carbons vertically he set them side by side, with an insulator in between to prevent an electric connection except at the tip where the arc was produced. This eliminated the need for a regulator to maintain spacing and therefore allowed wiring many lamps together. Yablochkov (or Jablochkoff) candles were used for public illumination in Paris and London in the late 1870s, powered by a further refinement to the dynamo devised by Belgian Zénobe Gramme.[12]
Charles Brush, an American, combined the improved generators coming out of Europe with a long-lasting and reliable arc lamp design that finally bring electric lighting into widespread commercial use. Brush worked a day job in Cleveland trading iron ore on the Great Lakes while inventing in his spare time in the workshop of his friend’s telegraph supply company. Like others had decades before him, he used an electromagnet to regulate the distance between the electrodes of the arc, but he added a “ring-clutch” which could feed out these long carbon rod in small increments each time the current weakened, like the lead of a mechanical pencil. He also found that rods made of a different kind of coke, derived from petroleum refining, and then electro-plated with copper, could be drawn longer and thinner than traditional carbon rods, for a longer burn. This allowed his lamps to provide about eight hours of steady light, then sixteen when he created a dual-carbon lamp.[13]
A key early client was Philadelphia businessman John Wanamaker, who operated the Grand Depot, of one of the first “department stores,” which would sell you almost everything under a single roof. On Christmas Day 1878, he threw the switch on twenty-eight new Brush lamps, powered by six generators. Three years later, he collaborated with other Philadelphia grandees to bring Brush lighting to the city’s streets. A brick-built power station near City Hall equipped with eight forty-five horsepower steam engines, each with its own dynamo, powered forty-nine arc lights set on red-painted iron poles along Chestnut Street from the Delaware to the Schuylkill.[14]
Brush’s electric light provides an opportunity to reflect on how much the steam engine’s technological role had changed over the previous century. From a free-standing power source for simple mechanical pumps, it had evolved into an embedded component of complex technological systems consisting of many interconnected and interdependent innovations: steamships, factories, railroads, and now city lighting, with still more complex electrical power systems to come. The steam engine had become a kind of mechanical mitochondrion, a life form captured and put to use to drive the workings of a still more complex organism, in many cases a pre-existing one (water-powered textile factories and horse-drawn railways, for example). These organisms could not succeed without the evolution of their component parts (engines, dynamos, lamps and circuits, in the case of Brush’s electric light) to a point where they could work in harmony with sufficient economy and simplicity to make the integrated whole of practical use.
Having achieved that point, electric arc lighting systems spread across the public spaces of the cities of North America, Europe, and even as far away as India and Australia, and everywhere it went it dazzled the public with its brilliant white light. When the town of Wabash, Indiana mounted Brush lights atop its courthouse in 1880, a correspondent from the Chicago Tribune reported a nigh-religious response:
[p]eople stood overwhelmed with awe, as if in the presence of the supernatural… Men fell on their knees, groans were uttered at the sight and many were dumb with amazement. We contemplated the new wonder in science as lightning brough down from the heavens.[15]
Gas
This was not the first time in living memory that the public had witnessed the dawn of a new era in public illumination. Prior to electricity, coal gas lamps had been the cutting-edge lighting technology of the nineteenth century. Gas lamps burned the fumes emitted from coal when it was cooked in air-free retorts: a toxic but flammable mix of methane, carbon monoxide, hydrogen and other gases. Natural philosophers had discovered that coal could be distilled into a flammable gas as early as the seventeenth century, but it was first developed it into a commercial light source in the first decade of the nineteenth.[16]
Factories were early adopters of the technology, which allowed them to operate long into the night, especially in the short days of a Northen European winter, and thus get more use out of their expensive machinery. Just as the steam engine had worn down the distinctions between seasons that determined the ebb and flow of water power, gas illumination eroded the ancient and powerful distinction between night and day more rapidly than any event since the taming of fire. We may to some degree consider the demand for artificial light as a natural result of humanity’s aversion to darkness, yet to some degree it was also a byproduct of modernity: the rise of capital-intensive, indoor industry and office work that depended on reading and writing created more work that could be done after sunset and more financial incentive to do it.
Among the earliest uses was at the cotton mill of George Lee in Salford, near Manchester, lit in 1805 by fifty gas lamps installed by Boulton and Watt, under the supervision of the same William Murdoch who had developed the sun-and-planet gear for that firm over twenty years earlier.[17] By mid-century, gas fumes were being stored in tanks and then piped out to factories, stores, street lights, offices, and wealthier homes in most of the major cities of the West. A gas mantle provided brighter light than a candle or oil lamp at lower marginal cost (once the original installation cost was defrayed) and with less risk of fire (since it was attached to a fixed pipes which could not tip over).
By the early 1880s, however, arc lighting was rapidly supplanting gas for public and commercial illumination: city streets, department stores, amusement parks, factories, and more. A reporter present at the lighting of Chestnut Street in Philadelphia noted that the existing public lighting appeared “yellow, dim, and sickly” by comparison, and the electric light could be cheaper even than gas.[18] Brush’s success drew competitors who copied and improved upon his creation, making gas still less attractive. Most notable was Elihu Thomson of Philadelphia, who figured out how to make a highly-efficient self-regulating dynamo that would maintain a steady current regardless of the number of working lamps, allowing individual lamps to fail or be switched off without the need for bypass circuits or some other compensating resistor.[19]
For all of its impressive advantages in brightness, clarity, and cost, however, arc lighting created a spectacle that was entirely unsuited to homes and offices. No one wanted a glaring, hot two-thousand candlepower arc lamp (about twenty times as bright as a typical modern light bulb) next to their desk or sofa. A different path to electric light would have to be taken in order to domesticate it.
Incandescence
The phenomenon of electric incandescence had also been known for many decades. An electric current sent through certain materials, such as a strip of platinum or rod of carbon, would cause that material to glow with a warm, mild light, of an entirely different character from the dazzling arc. Dozens of inventors throughout the nineteenth century tried to turn this effect into a practical electric light, but all suffered from the same basic limitation: the incandescent material burned or melted far too quickly to make a useful light source.
By 1878, several inventors had made some basic progress toward a practical system of incandescent electric light: Moses Farmer had developed a dynamo and incandescent bulbs that he used to light his own home in Cambridge, Massachusetts in the 1860s. Moses made little effort to commercialize his home experiment, but his partner William Wallace continued to manufacture Farmer’s dynamo design. In early 1879, Joseph Swan, an English industrial chemist, demonstrated a bulb with a filament of carbonized thread in a vacuum (to prevent the carbon from burning up). Sawyer, another native Yankee like Farmer, also developed a carbon incandescent lamp in a nitrogen-filled bulb, and plans for an electrical distribution system, but his excessive love of alcohol and rash temper made it impossible for him to secure steady partnerships and funding.[20]
Thomas Edison, inspired by a demonstration of arc lamps lit by dynamos at Wallace’s factory, launched his own electric light company in 1878. Already a successful and famous inventor due to his work on the telegraph, telephone, and phonograph, Edison’s reputation alone sufficed to tank the price of gas company stocks when he announced that he had entered the fray. He brought to bear both profound energy and far more capital than any of his rivals, with financial backing from the Western Union telegraph company and J.P. Morgan’s sprawling banking empire.[21]
At his “invention factory” in Menlo Park, New Jersey, he and his employees made an exhaustive search of materials to find an ideal filament. Everyone knew that long life was crucial, but Edison, already looking beyond the bulb (which he called a “burner,” by analogy to the gas light) to the complete electric system, had a further insight: he wanted a filament of high resistance. Swan and Sawyer had created low-resistance filaments to minimize loss of energy in the circuit to heat, but Edison realized that to effectively distribute electricity across a city, it was more important to minimize the cost of the copper wiring and generators: due to Ohm’s Law, high resistance meant low current, which meant thin and inexpensive wires.[22] Francis Upton and Charles Batchelor, two of Edison’s most trusted employees, carried out a series of experiments on a wide variety of materials: paper, fishing line, cotton thread, lampblack, cardboard, wood shavings of all kinds (from boxwood to spruce), cork, coconut shells, and more before finally settling on carbonized bamboo as the most effective. It resisted current at hundreds of ohms and proved capable of burning for hundreds of hours without failing.[23]
Then, like Brush but at an even more ambitious scale, Edison’s lab built a complete electrical system around his successful bulb. Out of Menlo Park came a new dynamo with a drum-shaped armature, a new vacuum pump design to remove the air from the bulb’s glass envelope as efficiently as possible, screw sockets for securely installing bulbs at any angle, meters, and switches. Newly designed conduits and junction boxes distributed of electricity along a “feeder-and-main” system which reduced the cost of copper by sending multiple thin feeder circuits out from the generator to the main circuits that powered the lights, rather than using a single thick trunk line.[24]
All of this ingenuity fed into the famous Pearl Street station in downtown New York, chosen because of its proximity to over one thousand existing gas customers whom Edison hoped to convert to electric light. When the station switched on in September 1882, among its initial customers were the offices of the New York Times, whose pages praised the light as a vastly superior alternative to gas:
…more brilliant than gas and a hundred time steadier… As soon as it is dark enough to need artificial light, you turn the thumbscrew and the light is there, with no nauseous smell, no flicker, and no glare… 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.[25]
In fact, generating the magical glow of the electric lamps required heat, glare, and noxious fumes aplenty, but they were hidden away from the customers in the lower floors of the Pearl Street station, where Babcock & Wilcox boilers fed steam to Armington & Sims engines which, in turn, spun Edison Electric’s “Jumbo” dynamos, named after P.T. Barnum’s famous elephant.[26] In the 1930s, historian cultural critic Lewis Mumford identified a divide between the grim steam-and-iron regime of the “paleotechnic” and the clean, bright, and electric “neotechnic.”[27] But to some extent this was a false distinction. Electricity distributed and subdivided steam power, it made it invisible, but, contrary to the dreams of the early electric enthusiasts, it did not replace it.[28]
Yet this is still not the whole of the truth of the relation between electricity and steam. Edison explicitly designed his lighting system as a one-to-one replacement for gas illumination. But his dreams extended far beyond an electrified equivalent of gas lighting to an all-encompassing system of power: “The same wire that brings the light to you,” Edison proclaimed in 1878, long before he even had a working incandescent bulb, “will also bring power and heat. With the power you can run an elevator, a sewing machine or any other mechanical contrivance that requires a motor, and by means of the heat you may cook your food.”[29]
Though far from reality in 1878, this vision did indeed come true, and it placed new demands on steam power that would require its reinvention, and the replacement of the century-old reciprocating steam engine with something altogether new.
