The Most Powerful Idea in the World

by William Rosen

  … yesterday we proceeded32 on our journey with the engine, and we carried ten tons of iron in five wagons, and seventy men riding on them the whole of the journey … the engine, while working, went nearly five miles an hour; there was no water put into the boiler from the time we started until our journey’s end … the coal consumed was two hundredweight.

  And, sort of, it didn’t. The problem lay less with the locomotive than with the rails, which cracked like twigs. The engine, whose five and a half tons were distributed over only four wheels, and with only two of them driving, put an unanticipated lateral strain on the railway. Though Trevithick would try again, on a coal railway in Newcastle in 1805, the rail problem remained unsolved; even in 1808, when Trevithick demonstrated his “Catch-Me-Who-Can” locomotive on a half-mile oval near Gower Street in London for a shilling a head, it was regarded more as a circus act than as any useful industrial advance.

  Trevithick’s engine, the first driven by high-pressure steam, earned him a considerable claim on the title “father of railways,” but the birth of steam locomotion was still a decade or so in the future. More important, though less romantic, was another of Trevithick’s innovations, one that was nearly as large an improvement over the first high-pressure design as that had been over the Boulton & Watt separate condensing engine—indeed, as big an improvement as Watt’s separate condenser was over Newcomen’s original atmospheric engine.

  For nearly a decade, Trevithick’s high-pressure engines had been making significant inroads into the dominant position of Boulton & Watt in Cornwall’s mines. By 1812, he determined to displace them once and for all. In a pump built for the Wheal Prosper mine in Cornwall, Trevithick modified his existing high-pressure steam design so that instead of exhausting the condensed steam directly to the atmosphere, as with the Penydarren and Camborne Hill engines, he allowed it to expand into a lower-pressure chamber first. In the new engine, the pressure on the piston came from both the expansive property of high-pressure steam on top of the piston and the atmospheric pressure on the chamber once the steam has been condensed. Steam flowed into the top half of the cylinder and pushed the piston down some distance, at which point a valve closed and the steam expanded to fill the now smaller volume. Trevithick, in comparing an early model to a Boulton & Watt atmospheric engine, discovered that he could produce 40 psi using one-third the coal that the atmospheric engine needed to produce 4 psi. Even more innovative, the new engine’s boiler lay horizontally, which allowed the fire tube to run through its middle, heating the water both efficiently and to high pressure. “My predecessors,” Trevithick said, “put their boilers in the fire;33 I have put the fire in the boiler.” The result, in 1812, was the first really successful “Cornish engine.”

  It was certainly successful as measured by the still-in-use benchmark of “duty,” which measured the pounds of water raised one foot by a bushel of coal. A high-performing Newcomen-style engine typically performed in the neighborhood of 5,000 pounds; Smeaton’s many improvements nearly doubled that number—to 9,600 pounds—without changing the basic design, and a 1778 Watt engine, with separate condenser, achieved a duty of 18,900 pounds. By 1812, Trevithick was boasting34 of 40,000 pounds, which is likely an exaggeration, but an objective report of three Cornish engines at the Dolcoath mine reported 21,400, 26,800, and 32,000 pounds in 1814. By 1835, another Cornish engine achieved a duty of 100,000 pounds.

  However, efficiency, as measured in duty, was not everything. The price of the Cornish engine’s dramatic achievement was that its multiple chambers and valves demanded an unforgiving level of both precision and maintenance. Without either, they were more subject to breakdowns—and to the purchaser of a steam engine trying to make delivery of a scheduled amount of cotton, produce a quantity of iron, or pump water, it mattered little to have the most efficient steam engine if it was out of commission for two days a week. As a result, it is the last advance in steam power with Trevithick’s name attached to it.

  Instead, like a homing pigeon, he returned to his origins: precious metals mining. Trevithick became obsessed with reopening the silver mines of Cerro de Pasco in Peru, which had once been among the richest of Spain’s possessions in the New World. Trevithick convinced himself that he would be able to make the Peruvian mines profitable once again, and he left Britain planning to do so in October 1816, arriving in February of the following year.

  His timing could have been better. By 1817, most of South America was in rebellion against Spain; the month before Trevithick arrived in Peru, the Argentine general José de San Martín had crossed the Andes into Chile and was preparing to head north. A month before that, Simón Bolívar had returned to Venezuela from Haiti. Though Peru would remain under Spanish control for another five years, Trevithick’s engines (he had shipped four pumping engines and four winding engines ahead of his arrival) were still in their crates when his romantic soul got the better of him and he joined the rebellion. While in Caxatambo, Peru, he even designed a new carbine for Bolívar’s army, but when the city was occupied by the Spaniards in 1818, Trevithick was forced to flee north35 to Costa Rica, leaving an estimated £5,000 in ore and uncounted more pounds’ worth of lost equipment.

  Trevithick’s South American adventure carries an almost unwieldy tonnage of symbolism: a representative of the dominant world power of the nineteenth century caught in the collapse of the dominant one of the sixteenth. Even more pointedly, it offers a high-contrast picture comparing history’s two longest-lasting approaches to the very idea of wealth: wealth as technology versus wealth as precious metals. Whatever meaning is retrospectively poured into it, however, the experience as Trevithick lived it seems to be less about the metaphorical war between two notions of political economy than about the real thing. Evading Spanish patrols in the Nicaraguan jungles, which the Cornish inventor was forced to traverse on foot, destroyed whatever romance the rebellion still offered. Trevithick’s journey, which included a dozen hair’s-breadth escapes, the deliberate capsizing of his boat by an offended traveling companion, and bouts of illness too frequent to count, found him arriving at last in Cartagena, Colombia, exhausted, sick, and broke—in his own words, “half-drowned, half-dead, and the rest devoured by alligators.”36

  There his story took an unlikely turn. In Cartagena, he met the son of an old friend, who lent him £50 for his fare home. When Trevithick finally returned in 1827, he had nothing on his person to show for a decade in South America but two compasses—one for drafting, the other for navigating—a pair of silver spurs, and his gold watch.

  Aficionados of dramatic coincidences could, however, take some comfort in the name of the man who paid for Richard Trevithick’s ticket home. He was Robert Stephenson, of Newcastle, and along with his father, George, is Trevithick’s only serious competitor for the title of “father of railways.”

  THE DEPICTION OF GEORGE STEPHENSON by Samuel Smiles, the prolific biographer and self-help author* who did more than anyone else to establish the heroic archetype for British inventors, is a textbook example of self-discipline and deferred gratification. His first job was as a picker: a laborer whose entire job was separating coal from the stones that accompanied it from mineshaft to colliery. Soon enough he was working as an assistant fireman, then as the “plugman” operating a set of valves on the steam-driven pump at another collier’s. When he turned twenty, he was appointed as the brakeman, responsible for maintaining the winding mechanism that pulled the coal-filled buckets from the work area of the mine.

  None of this permitted much time for education, even of the practical sort, and in a previous century, Stephenson might have simply become a superbly reliable artisan. By the end of the eighteenth century, however, Britain—particularly outside London—had spent decades making heroes out of onetime laborers who had become wealthy by acquiring and producing useful knowledge. So inspired, Stephenson taught himself to read and write and hired someone to teach him the rudiments of arithmetic. By 1801, the ambitious twenty-two-year-old brakeman to
ok on additional work moonlighting as a watch repairman; two years later, now a father, he took charge of the Boulton & Watt steam engine driving the wheels of a Scottish spinning factory that had grown prosperous making cloth for the military uniforms needed for the war against Napoleon. This did not exempt Stephenson from service himself, nor did the birth of his son, Robert, in 1803; the following year he was drafted for the militia, and went into debt paying for a substitute to serve in his place. The same year, he returned to the Killingworth pit mine, where he taught himself mechanical engineering by spending his one day off each week dismantling and reassembling the colliery’s steam engine.

  In 1811, Stephenson, like Watt thirty years before, made his first real mark on the world repairing a Newcomen engine, this one an old model at one of the Killingworth pits. For the job he was paid £10, and far better, was hired to manage all the engines owned and operated by the collieries of the so-called “grand allies,” a group of aristocratic investors that owned the Killingworth pit, at the impressive salary of £100 per year—the equivalent of more than $100,000 in current dollars.37 Stephenson’s salary was an insurance policy for the stationary engines on which the colliers depended; it rapidly turned into an investment in an entirely new industry. In 1814, Stephenson built his first locomotive to transport coal at Killingworth: the Blucher, a giant step toward practical steam locomotion.

  • • •

  THE TWO GREAT PROBLEMS in harnessing steam power for transportation were, broadly speaking, both a function of weight. The first one—increasing the engine’s power-to-weight ratio—was addressed, if not solved, by the realization, by both Evans and Trevithick, that more heat meant more pressure and therefore more work. That notion, which is obvious in retrospect but was revolutionary at the time, practically demanded a whole series of “micro-inventions” intended to turn up the dial on steam boilers: return flues, for example, which not only “put the fire in the boiler” but increased exponentially the area heating the water. Even more important, exhausting the steam through a chimney located above the furnace created a draft—a “steamblast”—that raised the heat even further.

  The other weight problem was the one that licked Trevithick at Penydarren: The tracks on which the locomotive ran were just not able to survive the tonnage traveling over them. Driving a five-ton steam locomotive over rails designed for horse-drawn carts was only slightly more sensible than driving a school bus over a bridge made of wet ice cubes. In both cases, it’s a close call whether the vehicle will skid before or after the surface collapses.

  This is why all of the dozens of inventors attempting to put steam on the move were obsessed with the durability and traction of the surface holding their vehicles; for centuries, the rails originally designed for horse transport had been made of wood, occasionally reinforced with iron edging. Not until 1767 did the Darbys of Coalbrookdale begin casting iron rails for wagonways, which made them far stronger; within twenty years some unknown innovator had added an arched rim, or lip, to prevent wheels from slipping off.

  The rims, or flanges, were fine for keeping the wheels from moving laterally, but they did nothing to increase traction—a real challenge for smooth iron wheels on smooth iron rails. In 1811, John Blenkinsop, an employee of another collier located in the city of Leeds, patented a Trevithick-style engine with a cogged driving wheel, and accompanied this with a new sort of track, this one made of cast iron with an edge rail carrying a toothed rack. The cog-and-rack not only eliminated any possibility of skidding, it transmitted five times the force of Trevithick’s original engine, and Blenkinsop-style engines remained popular through the 1820s, despite the enormous cost of producing miles of what were essentially horizontal iron gears.

  Two years later, a civil engineer named William Chapman applied for and received a patent for an engine that propelled itself by hauling itself along a chain; even odder, William Brunton also managed to patent his “Brunton Mechanical Traveler” that “walked” the locomotive along by operating mechanical feet driven via a complicated series of levers and linkages. Slightly less eyebrow-raising,38 in 1815, William Hedley’s “Wylam Dylly” engine tried to solve the excess weight problem by doubling the axles from two to four, thus distributing the weight over a larger area.

  Stephenson’s locomotive, which made its maiden journey on July 25, 1814, took a different approach. The engine driving the Blucher (named for the Prussian general who would pull the Duke of Wellington’s chestnuts out of the fire at Waterloo almost exactly a year hence) incorporated an early version of the blastpipe: a vertical tube with a narrowed exit that carried the exhaust into the chimney, creating a draft, just as Trevithick had more or less accidentally discovered a decade before. It also ran on a reversed version of the most popular track design, putting a flanged wheel on a smooth rail. Two years later, Stephenson, in collaboration with the ironmonger William Losh of Newcastle, produced, and in September 1816 jointly patented, a series of improvements in wheels, suspension, and—most important—the method by which the rails and “chairs” connected one piece of track to another. Stephenson’s rails seem mundane next to better-known “eureka” moments, but as much as any other innovation of the day they underline the importance of such micro-inventions in the making of a revolution. For it was the rails that finally made the entire network of devices—engine, linkage, wheel, and track—work.

  Stephenson’s working life* marks the point in the development of steam technology when the value of what economists call “network effects” finally overtook the importance of any individual invention, however brilliant. Setting the distance between the smooth tracks on which the Blucher traveled at four feet eight and a half inches was arbitrary—that was the width of the Killingworth Colliery wagonway—but its specific width was irrelevant. The value of any standard is not its intrinsic superiority, but the number of people using it. Like the famous example of the QWERTY keyboard, the Stephenson gauge became the world standard, and it is still the width used on more than 60 percent of the world’s railroads.

  Of course, simply laying rails a particular distance apart does not make for a monopoly unless others follow. And others weren’t about to follow Stephenson’s lead until they were persuaded that there was some advantage to it, in the form of either increased revenue or lower costs. To a proprietary line, such as the ones that connected coal mines with ports, the advantage of a standard wasn’t all that obvious; as at Killingworth, it was frequently more economical to use existing wagonways and roads than to redesign them to a new standard. The same didn’t apply to so-called “common carriers,” who needed, by definition, to accommodate rolling stock they didn’t own, or to travel on railways they didn’t build. The first common carrier to realize this,39 the Stockton and Darlington Railway, was, not at all coincidentally, one of George Stephenson’s employers. But by far the most important one was the one intended to connect the cities of Manchester and Liverpool.

  It is almost indecently tempting to place the Liverpool & Manchester Railway at the climax of the entire history of British industrialization. The first temptation is posed by Manchester itself, which was, when George Stephenson took on the job as chief engineer of the proposed railway in 1825, the most “industrial” spot in all England, with all that implied: “a town of red brick,” in the words of Charles Dickens, “or of brick that would have been red if the smoke and ashes had allowed it.”

  The reason, of course, that those bricks were covered by smoke and ash was that the city was home to the world’s largest textile manufacturers, factories that used coal to turn cotton into clothing. Richard Arkwright’s mills, which gave the city its nineteenth-century nickname of “Cottonopolis,” had become so successful that the choke point for the industry’s growth was no longer technological imbalance (the difference between efficient spinners and inefficient weavers, for example) but transportation. Manchester was making cotton faster than it could ship it, and Britain’s canal system, even with its sophisticated locks, was less and less a
ble to handle the load, which was easily exceeding a thousand tons of cargo daily: raw cotton in, finished goods out. So much cloth was being made in Manchester, in fact, that by 1800, the port of Liverpool on the River Mersey was the world’s most important; less than eighty years old, it handled more than a third of all the world’s trade. The need for a railway to connect Manchester’s mills with the port city had become urgent.

  It is metaphorically satisfying to talk about threads being woven together when talking about cotton, but the thread that mattered to the Liverpool & Manchester Railway was made of iron: thirty miles of it, smelted, forged, and wrought in ironworks like Coalbrookdale on the Severn, and laid down as rails between the two cities that were now producing, in their mundane way, more wealth in a year than the entire Roman Empire could in a century.

  But while there were clearly massive financial incentives for building some kind of railway between the factory and the port, the railway’s directors were uncertain that a locomotive railway was the best option. Some of the investors and directors in the enterprise were promoting the use of rope cables to haul boxcars full of cotton the entire thirty miles, using stationary engines roughly every mile and a half. Others wanted different kinds of locomotives (though no one, happily, was arguing on behalf of Brunton’s mechanical “walker”). After much to-ing and fro-ing, it was decided to settle the problem with a contest.

  On May 1, 1829, the Liverpool & Manchester Railway ran an advertisement in the Liverpool Mercury inviting “engineers and iron founders” to submit plans for locomotives to compete for the winning design. The offer of a £500 prize, the equivalent in average earnings of more than $500,000 in 2010, brought the crackpots out in force. The treasurer of the Liverpool & Manchester, Henry Booth, described the applications: