Читать книгу Exactly: How Precision Engineers Created the Modern World - Simon Winchester, Simon Winchester - Страница 10
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Extremely Flat and Incredibly Close
It is to the exactitude and accuracy of our machine tools that our machinery of the present time owes its smoothness of motion and certainty of action.
—SIR WILLIAM FAIRBAIRN, BT. (1862), REPORT OF THE BRITISH ASSOCIATION FOR THE ADVANCEMENT OF SCIENCE
On the north side of London’s Piccadilly, overlooking Green Park and sandwiched between the quarters of the aged and imperturbable Cavalry Club to the west and a rather more ephemeral Peruvian-style ceviche restaurant on its eastern side, stands Number 124, these days an elegant but somewhat anonymous structure providing offices for the discreet and service apartments for the wealthy.
Since 1784, when this far-western end of the great boulevard was still ripe for development, the address had been the home and atelier of a cabinet, engine, and lock maker named Joseph Bramah. On fair-weather days some six years after its opening, when Bramah and Company was an established and familiar small firm, modest gatherings of curious passersby would assemble outside to peer into the front bow window, puzzling at a challenge so difficult that it went unanswered for more than the sixty subsequent years.
There was just a single object on view in the window, placed on a velvet cushion like a religious icon. It was a padlock, oval shaped, of modest size, and with a smooth and uncomplicated external appearance. On its face was written, in a small script legible only to those who pressed their faces close to the window glass, the following words: THE ARTIST WHO CAN MAKE AN INSTRUMENT THAT WILL PICK OR OPEN THIS LOCK SHALL RECEIVE 200 GUINEAS THE MOMENT IT IS PRODUCED.
Joseph Bramah, locksmith extraordinaire, also invented the fountain pen, a device for keeping beer cool and under pressure in a pub basement, and a machine for counting banknotes.
The designer of this boastfully unbreakable lock was the firm’s principal, Joseph Bramah. Its maker, however, was not Bramah but a then-nineteen-year-old former blacksmith’s apprentice named Henry Maudslay, whom Bramah had taken on the previous year, entirely because of Maudslay’s reputation for having a formidable skill in delicate machining.
It would not be until 1851 that the Bramah lock was successfully—although, as we shall see in a later chapter, controversially—picked and the very handsome pledge* redeemed. And in the years leading up to this event (which only their descendants would survive to witness), these two men, Bramah and Maudslay, proved themselves to be engineers supreme. They invented all manner of intriguing new devices, and they effectively and independently wrote the rule books for the precise world that was beginning to emerge as a consequence of (or, at least, in the wake of) John Wilkinson’s achievements with his cylinder-boring machine at Bersham. Some of the two men’s inventions have faded away into history; some others, however, have survived as the foundations on which much of today’s most sophisticated engineering achievements would eventually be built.
Though Maudslay remains today the better-known figure, with a legacy recognized by most engineers, Bramah was at the time perhaps the more showily ingenious of the pair. His first invention was dreamed up while he lay in bed after a fall, and must rank as the least romantic: for a London population that sorely needed an improvement in public hygiene, he built water closets, and he patented his ideas for a system of flaps and a float and valves and pipes that made the device both self-cleansing (flushing, indeed, for the first time) and free from the usual risk of freezing in winter that created unpleasant results for all. He made a small fortune from this creation, selling six thousand in the first twenty years of production, and a Bramah WC was still the centerpiece of the civilized English middle-class bathroom right up until Victoria’s Jubilee, a hundred years later.
Bramah’s interest in locks, which required far more intricacy and precise workmanship than a toilet, of course, seems to have started when he was elected in 1783 a member of the newly formed (and still there, in its original home) Royal Society for the Encouragement of Arts, Manufactures and Commerce.* What is now simply the Royal Society of Arts, the RSA, back in the eighteenth century had six divisions: Agriculture, Chemistry, Colonies and Trade, Manufactures, Mechanicks (spelled thus), and most quaintly, the Polite Arts. Bramah not unnaturally opted to attend most of the Mechanicks meetings and, soon after joining, rocketed to prominence by the simple act of picking a lock. Not so simply, actually: in September 1783, a Mr. Marshall had submitted for consideration what he declared was a formidably unpickable lock, and had a local expert named Truelove worry away at it with a quiverful of special tools for an hour and a half, before accepting defeat. Then, from the back of the audience stepped Joseph Bramah, who quickly fashioned a pair of instruments and opened the lock in fifteen minutes flat. A buzz of excitement went around the room: they were clearly in the presence of a most Mechanickal man.
Locks were a British obsession at the time. The social and legislative changes that were sweeping the country in the late eighteenth century were having the undesirable effect of dividing society quite brutally: while the landed aristocracy had for centuries protected itself in grand houses behind walls and parks and ha-has, and with resident staff to keep mischief at bay, the enriched beneficiaries of the new business climate were much more accessible to the persistent poor. They and their possessions were generally both visible and, especially in the fast-growing cities, nearby; they tended to live in houses and on streets within earshot and slingshot of the vast armies of the impoverished. Envy was abroad. Robbery was frequent. Fear was in the air. Doors and windows needed to be bolted. Locks had to be made, and made well. A lock such as Mr. Marshall’s, pickable in fifteen minutes by a skilled man, and by a desperate and hungry man maybe in ten, was clearly not good enough. Joseph Bramah decided he would design and make a better one.
He did so in 1784, less than a year after picking the Marshall lock. His patent made it almost impossible for a burglar with a wax-covered key blank, the tool most favored by the criminals who could use it to work out the position of the various levers and tumblers inside a lock, to divine what was beyond the keyhole, inside the workings. Bramah’s design, which he patented that August, had the various levers inside a lock rise or fall to different positions when the key was inserted and turned to release the bolt, but then had those same levers return to their initial positions once the bolt had been shot. The effect of this was to make the device almost burglar-proof, for no amount of foraging with a wax key blank would ever allow a picklock to work out where the levers needed to be (as they weren’t there anymore) in order to free the bolt.
Once Bramah had come up with this basic mechanical premise, it remained for him, with great cleverness and elegance, to form the entire lock into a cylindrical shape, with its levers not so much rising and falling under the influence of gravity as moving in and out along the radii of the cylinder under the impress of the key’s various teeth, and then moving back to their original positions with the aid of a spring, one for each lever. The entire lock could thus be rendered as a small tube-shaped brass barrel, which could be easily fitted into a tube-shaped cavity in a wooden door or an iron safe, and with the deadbolt flush to the door’s outer edge (when the lock was open) or settled into its brass cavity in the door frame (when securely closed).
Joseph Bramah would go on to invent many more contraptions and concepts during his life, many of them having nothing to do with locks, but involving his particular other fascination with the behavior of liquids when subjected to pressure. He invented the hydraulic press, for example, with its vast importance in industry worldwide. More trivially, he launched onto the market a primitive form of fountain pen* and drew designs for a propelling pencil; more lastingly, he made the beer engine, which is still employed by the more traditionally minded innkeepers, and which would allow beer kept cool in a cellar to be pressure-delivered to thirsty customers in the bar above. (This invention obviated the need for the bartender to stagger up and down the cellar stairs, lugging fresh barrels of ale.) Draft beer drinkers today have little cause to remember the name “Bramah,” though there is a pub in Lancashire named for him. Likewise, few banknote printers know that it was Joseph Bramah who made the first machine that could cleverly ensure that their thousands of identical bills each bore a different sequential number. He also made an engine for planing large wooden planks, another for making paper, and he forecast that, one day, large screws would be used to propel big ships through the water.
Yet it is really only by way of his lock making that Bramah’s name has now formally entered the English language. True, one can still find in literature references to a Bramah pen and a Bramah lock—the Duke of Wellington wrote admiringly of each, as did Walter Scott and Bernard Shaw. Yet when the word is used alone—and Dickens did on numberless occasions, in The Pickwick Papers, in Sketches by Boz, in The Uncommercial Traveller—it is a reminder that at least for the Victorian citizenry, his was an eponym: one used a Bramah to open a Bramah, one’s home was secured with a Bramah, one gave a Bramah to a favored friend so he or she might visit at all hours, come what may. Only when Mr. Chubb and Mr. Yale arrived on the scene (noted by the Oxford English Dictionary as first making it into the language in 1833 and 1869, respectively) did Joseph Bramah’s lexical monopoly hit the buffers.
What made a Bramah lock so good was its vastly complicated internal design, of course, but what made it so lastingly good was the precision of its manufacture. And that was less the work of its inventor than of the man—the boy, really—whom Bramah hired to make copious numbers of his device and to make them well, to make them fast, and to make them economically. Henry Maudslay was eighteen years old when Bramah lured him away as an apprentice: he would go on to become one of the most influential figures in the early days of precision engineering, his influence being felt to this day both in his native Britain and around the world.
The very young Maudslay, “a tall, comely young fellow” by the time Bramah hired him, cut his teeth in the Woolwich Royal Arsenal in East London. Working first as a twelve-year-old powder monkey—small boys, fleet of foot, were used by the Royal Navy to bring gunpowder down from the ships’ magazines to the gun deck—he was then moved to the carpenter’s shop, only to pronounce himself bored by the inaccuracy of wood. It was starkly clear to all who employed him that the youngster much preferred metal. They looked away when he smuggled himself into the dockyard smithy, and they said nothing when he developed a sideline in making a range of useful and very handsome trivets out of cast-off iron bolts.
IN 1789, JOSEPH Bramah cut an anxious figure. The political situation across the Channel was causing an influx of terrified French refugees, most of them bound for London, where the more nervously xenophobic residents of England’s capital suddenly started to demand ever more security for their homes and businesses. Bramah, with his patent-protected monopoly, was caught in a bind: he alone could make his locks, but neither he nor any engineer he could find had the ability to make them in sufficient numbers at a low enough price. Most men who called themselves engineers may have been adept at the cruder crafts—at thumping ingots of heat-softened iron with heavy hammers and then working to shape the crudely formed results with anvils, chisels, and, most especially, files—but few had a great feel for delicacy, for the construction of (and the word had only recently been adopted) mechanisms.
Change was coming, though. Workers at the smithies of eighteenth-century London were a close-knit group, and word eventually did reach Bramah that a particular youngster at Woolwich was startlingly unlike his older peers and, rather than bashing hunks of iron, was apparently crafting metal pieces of an unusual, fastidious daintiness. Bramah interviewed the teenage Maudslay. Though taking to him immediately, the former was only too well aware that the custom was for any would-be entrant to the trade to serve a seven-year apprenticeship. However, commercial need trumped custom: with would-be patrons beating down his door back on Piccadilly, Bramah had no time to spare for the niceties, decided to take a chance, and hired the youngster on the spot. His decision was to change history.
Henry Maudslay turned out to be a transformative figure. First of all, he solved Bramah’s supply problems in an inkling—but not by the conventional means of hiring workers who would make the locks one by one through the means of their own craftsmanship. Instead, and just like John Wilkinson two hundred miles west and thirteen years earlier, Maudslay created a machine to make them. He made a machine tool: in other words, a machine to make a machine (or, in this case, a mechanism). He built a whole family of machine tools, in fact, that would each make, or help to make, the various parts of the fantastically complicated locks Joseph Bramah had designed. They would make the parts, they would make them fast and well and cheaply, and they would make them without the errors that handcrafting and the use of hand tools inevitably bring in their train. The machines that Maudslay made would, in other words, make the necessary parts with precision.
Three of his lock-making devices can be seen today in the Science Museum in London. One is a saw that cut the slots in the barrels; another—perhaps less a machine tool than a means of ensuring that production went along at high speed, with every part made exactly the same—is a quick-grip, quick-release vise, a fixture that would hold the bolt steady while it was milled by a series of cutters mounted on a lathe; and the third is a particularly clever device, powered by a foot-operated treadle, that would wind the lock’s internal springs and hold them under tension as they were positioned and secured in place until the outer cover, a well-shined brass plate with the flamboyant signatures of the Bramah Lock Company of 124 Piccadilly, London, inscribed on its face, was bolted on to finish the job.
A fourth and, some would argue, most supremely important machine tool component also started to make its widespread appearance around this time. It would shortly become an integral part of the lathe, a turning device that, much like a potter’s wheel, has been a mechanical aid to the betterment of human life since its invention in pharaonic Egypt. Lathes evolved very slowly indeed over the centuries. Perhaps the biggest improvement came in the sixteenth century, with the concept of the leadscrew. This was a long and (most often, in early times) wooden screw that was mounted under the main frame of the lathe and could be turned by hand to advance the movable end of the lathe toward or away from the fixed end. It could do so with a degree of precision; one turn of the handle might advance the movable part of the lathe by an inch, say, depending on the pitch of the leadscrew. It gave wood turners working on a lathe a much greater degree of control, and allowed them to produce things (chair legs, chess pieces, handles) of great decorative beauty, symmetric loveliness, and baroque complexity.
Henry Maudslay then improved the lathe itself by many orders of magnitude—first by making it of iron, forging its structure stoutly and heavily, and at a stroke allowing it not merely to machine wooden items, but also to create symmetry out of shapeless billets of hard metal, which the flimsy lathes of old were incapable of doing. This alone might have been sufficient for us to remember the man, but then Maudslay employed one further component on his working lathes, a component whose origins are debated still, however, with the tenor of the debate pointing to an endless argument that complicates the historiography of precision and precision engineering.
Henry Maudslay, once a “tall, comely fellow,” machined the innards of Bramah’s locks and went on to become the founding father of precision toolmaking, mass production, and the key engineering concept of achieving perfect flatness.
Specifically, the device in question mounted on Maudslay’s lathes is known as a slide rest, a part that is massive, strongly made, and securely held but movable by way of screws, and is intended to hold any and all of the cutting tools. It is filled with gears that allow for the adjustment of the tool or tools to tiny fractions of an inch, to permit the exact machining of the parts to be cut. The slide rest is necessarily placed between the lathe’s headstock (which incorporates the motor and the mandrel that spins the workpiece around) and the tailstock (which keeps the other end of the workpiece secure). The leadscrew—Maudslay’s was made of metal, not wood, and with threads much closer together and with a more delicate pitch than was possible for a wooden version—advances the workpiece. The tools held on the slide rest can then be moved across the path of travel dictated by the leadscrew, thereby allowing the tools to make holes in the workpiece, or to chamfer it or (in due course, once milling had been invented, a process related in the next chapter) mill it or otherwise shape it to the degree that the lathe operator demands. So the leadscrew moves the workpiece longitudinally, and the slide rest that holds the tools that cut or chamfer or make holes in the workpiece moves transversely, or in all sorts of directions that are across the path made by the leadscrew.
Metal pieces can be machined into a range of shapes and sizes and configurations, and provided that the settings of the leadscrew and the slide rest are the same for every procedure, and the lathe operator can record these positions and make certain they are the same, time after time, then every machined piece will be the same—will look the same, measure the same, weigh the same (if of the same density of metal) as every other. The pieces are all replicable. They are, crucially, interchangeable. If the machined pieces are to be the parts of a further machine—if they are gearwheels, say, or triggers, or handgrips, or barrels—then they will be interchangeable parts, the ultimate cornerstone components of modern manufacturing.
Of equally fundamental importance, a lathe so abundantly equipped as Maudslay’s was also able to make that most essential component of the industrialized world, the screw.
Over the centuries, there were many incremental advances in screw making, as we shall see, but it was Henry Maudslay (once he had invented or mastered or improved or in some other manner become intimately associated with the slide rest on his lathe) who then devised a means of cutting metal screws, efficiently, precisely, and fast. Much as Bramah had a lock in his workshop window on Piccadilly, for reasons of pride as much as for his famous challenge, so Maudslay, Sons and Field placed in the bow window of the firm’s first little workshop, on Margaret Street in Marylebone, a single item of which the principal was most proud—and that was a five-foot-long, exactly made, and perfectly straight industrial screw made of brass.
Technically, Maudslay was not the first to perfect a screw-making lathe. Twenty-five years earlier, in 1775, Jesse Ramsden, a scientific instrument maker in Yorkshire who was funded by the same Board of Longitude for which the clockmaker John Harrison had labored, and who was not allowed to patent his invention, had made a small and exquisite screw-cutting lathe. This could cut tiny screws with as many as one hundred twenty-five turns to the inch—meaning it would take one hundred twenty-five turns to advance the screw by one inch—and so would allow the tiniest adjustments to any device to which the screw was harnessed. But Ramsden’s was effectively a one-off machine, as delicate as a watch, meant for work with telescopes and navigational instruments, and in no way destined for the making of large-scale devices made of much metal and that could work at great speed and maintain accuracy and be durable. What Maudslay had done with his fully equipped lathe was to create an engine that, in the words of one historian, would become “the mother tool of the industrial age.”
Moreover, with a screw that was made using his slide rest and his technique, and with a lathe constructed of iron and not with the wooden frame he and Bramah had used initially, he could machine things to a standard of tolerance of one in one ten-thousandth of an inch. Precision was being born before all London’s eyes.
So, whoever did invent the slide rest can take the credit for the later precise manufacture of countless components of every conceivable size and shape and relevance to a million and one machined objects. The slide rest would allow for the making of myriad items, from door hinges to jet engines to cylinder blocks, pistons, and the deadly plutonium cores of atomic bombs—as well as, of course, the screw.
But just who did invent it? Not a few say Henry Maudslay, and that he did so in Joseph Bramah’s “secret workplace [which] contained several curious machines … constructed by Mr. Maudslay with his own hands.” Others say it was Bramah. Still others refute the idea of Maudslay’s involvement entirely, saying definitively that he did not invent it, nor ever claimed to have done so. Encyclopedias say the first slide rest was actually German, having been seen illustrated in a manuscript in 1480. Andrey Nartov, the Russian scientist who had the eighteenth-century title of personal craftsman to Tsar Peter the Great, was revered as the greatest teacher of lathe operation in Europe (and taught the methods to the then-king of Prussia) and is said to have made a working slide rest (and taken it to London to show it off) as early as 1718. And just in case the story from St. Petersburg has any doubters, a Frenchman named Jacques de Vaucanson quite provably made one in 1745.
Chris Evans, a professor in North Carolina who has written extensively about the early years of precision engineering, notes the competing claims, and cautions against the “heroic inventor” treatment of the story. Far better to acknowledge, he says, that precision is a child of many parents, that its advances invariably overlap, that there are a great many indeterminate boundaries between the various disciplines to which the word precision can be attached, and that it was, in its early days, a phenomenon that evolved steadily over three centuries of ever-lessening bewilderment. It is, in other words, a story far less precise than its subject.
That being said, Henry Maudslay’s principal legacy is a wholly memorable one, for other inventions and involvements followed his association with Joseph Bramah, from whose employ he left, in a huff, after his request for a raise—he was making thirty shillings a week in 1797—was turned down too curtly for his taste.
MAUDSLAY PROMPTLY PROCEEDED to free himself from the circumscribed world of West London lock making, and he entered—one might say, he inaugurated—the very different world of mass production. He created in the process the wherewithal for making, in truly massive numbers, a vital component for British sailing ships. He built the wondrously complicated machines that would, for the next one hundred fifty years, make ships’ pulley blocks, the essential parts of a sailing ship’s rigging that helped give the Royal Navy its ability to travel, police, and, for a while, rule the world’s oceans.
This all came about in a moment of the happiest chance, and just as with Bramah and the lock in Piccadilly, it involved a shopwindow (Henry Maudslay’s) and the proud public showroom display of the five-foot-long brass screw Maudslay had made on his lathe and which he had placed there, center stage, as an advertisement of his skills. Soon after he set up the screw display, so naval legend has it, came the serendipitous moment. It involved the two figures who were going to create the pulley block factory, and who vowed to do so properly, to fill an urgent and growing need.
A block-making factory of sorts had already been set up in the southern dock city of Southampton in the mid-eighteenth century, performing some of the sawing and morticing of the wooden parts, but much of the finishing work still had to be done by hand, and in consequence, the supply chain remained unreliable at best. And a reliable supply chain was seen to be vital for England’s survival.
Britain had been at war with France, on and off, for much of the late eighteenth century, and the arrival on the scene of Napoleon Bonaparte in the aftermath of the French Revolution convinced London that her forces needed to be at the ready for much of the early nineteenth century, too. Of the two British fighting forces, the army and the Royal Navy, it was the admirals who took the lion’s share of the war budget, and Britain’s docks were soon bristling with big ships ready to cast off at a moment’s notice to give any French opponents, Napoleon’s especially, a taste of the lash. Shipyards were busy building, dry docks were busy repairing, and the seas from the Channel to the Nile, from the Barbary Coast to Coromandel, were alive with great British men-o’-war, powerful and watchful, ceaselessly on the prowl.
These were, of course, all sailing vessels. Mostly they were enormous craft with wooden hulls and copper-sheathed keels, with three decks ranged with cannon, with enormous masts of Norfolk Island pine supporting equally vast acreages of canvas sailcloth. And all the sail ware of the time were bolts of canvas suspended, supported, and controlled by way of endless miles of rigging, of stays and yards and shrouds and footropes, most of which had to pass through systems of tough wooden pulleys that were known simply to navy men as blocks—pulley blocks, part of a warship’s arrangements known within and beyond the maritime world as block and tackle.
A large ship might have as many as fourteen hundred pulley blocks, which were of varying types and sizes depending on the task required. A block with a single pulley might be all that was needed to allow a sailor to hoist a topsail, say, or move a single spar from one location to another. The lifting of a very heavy object (an anchor, for example) might need an arrangement of six blocks, each with three sheaves, or pulleys, and with a rope passing through all six such that a single sailor might exert a pull of only a few easy pounds in order to lift an anchor weighing half a ton. Block-and-tackle physics, taught still in some good primary schools, shows how even the most rudimentary pulley system can offer the greatest of mechanical advantage, and combines this power with an equally great degree of simplicity and elegance.
Blocks for use on a ship are traditionally exceptionally strong, having to endure years of pounding water, freezing winds, tropical humidity, searing doldrums heat, salt spray, heavy duties, and careless handling by brutish seamen. Back in sailing ship days, they were made principally of elm, with iron plates bolted onto their sides, iron hooks securely attached to their upper and lower ends, and with their sheaves, or pulleys, sandwiched between their cheeks, and around which ropes would be threaded. The sheaves themselves were often made of Lignum vitae, the very same hard and self-lubricating wood that John Harrison used for the gear trains of some of his clocks: most modern blocks have aluminum or steel sheaves and are themselves made of metal, except where the desired look of the boat is old-fashioned, in which case there is much showy brassware and varnished oak.
Hence the early nineteenth-century Royal Navy’s acute concern. An increasingly fractious Napoleonic France lay just twenty miles away across the Channel, and countless maritime problems were demanding Britain’s maritime attentions elsewhere: what principally concerned the admirals was not so much the building of enough ships but the supply of the vital blocks that would allow the sailing ships, to put it bluntly, to sail. The Admiralty needed one hundred thirty thousand of them every year, of three principal sizes, and for years past, the complexity of their construction meant that they could be fashioned only by hand. Scores of artisanal woodworkers in and around southern England were originally bent to the task, a supply system that proved notoriously unreliable.
As hostilities at sea became ever more commonplace, as more and more ships were ordered, the drumbeat for a more efficient system became ever louder. The then–inspector general of naval works, Sir Samuel Bentham, finally decided he would act; he would sort things out. And in 1801, Bentham was approached by a figure named Sir Marc Brunel, who said he had in mind a specific scheme for doing so.*
Brunel, a royalist refugee from the very French instability currently so vexing the Lords of the Admiralty—though he had first immigrated to America and become New York’s chief engineer before returning to England to marry—had sized up the mechanics of the block-making problem. He knew the various operations that were necessary to make a finished block—there were at least sixteen of them; a block, simple though it might have looked, was in fact as complex to make as it was essential to employ—and he had roughed out designs for machines that he thought could perform them.* He sought and, in 1801, won a patent: “A New and Useful Machine for Cutting One or More Mortices Forming the Sides of and Cutting the Pin-Hole of the Shells of Blocks, and for Turning and Boring the Shivers, and Fitting and Fixing the Coak Therein.”
His design was, in more ways than one, revolutionary. He had one machine perform two separate functions—a circular saw, for example, could perform the duties of a mortice cutter as well. He had the surplus motion of one machine drive its neighbor, maintaining a kind of mechanical lockstep. The necessary coordination of the machines one with the other required that the work each machine performed be accomplished with the greatest precision, for a wrong dimension passed into the system by one wrongly set machine would act much as a computer virus does today, amplifying and worsening by the minute, ultimately infecting the entire system, and forcing it to shut own. And rebooting a system of enormous iron-made steam-powered machines with flailing arms and whirling straps and thundering flywheels is not just a matter of pressing a button and waiting half a minute.
Given the complexity of the system he had sold to the navy, it was essential only for Brunel to find an engineer who would and could construct such a set of never-before-made machines, and ensure that they were capable of the repetitious making, with great precision, of the scores of thousands of the wooden pulley blocks the navy so keenly needed.
This is where Henry Maudslay’s window comes in. An old friend of Brunel’s from his French days, another migrant, named M. de Bacquancourt, happened to pass by the Maudslay workshop on Margaret Street and saw, prominent in the bow window, the famed five-foot-long brass screw that Maudslay himself had made on his lathe. The Frenchman went inside, spoke to some of the eighty employees in the machine shop, and then to the principal himself, and came away firm in the belief that if one man in England could do the work Brunel needed, here he was.
So Bacquancourt told Brunel, and Brunel met Maudslay out at Woolwich. As part of the interview, Brunel then showed the youngster an engineering drawing of one of his proposed machines—whereupon Maudslay, who was able to read drawings in the same way that musicians can read sheet music with the facility that others read books, recognized it in an instant as a means of making blocks. Models of the proposed engines were constructed to show the Admiralty just what was envisioned, and Maudslay set to work, with a formal government commission.
He was to devise and build, as specified in Brunel’s drawings, the first precision-made machines in the world that would be established for the sole purpose of manufacturing items. In this case it was pulley blocks, but the items could just as well have been guns, or clocks, or, in time to come, cotton gins or motorcars—en masse.
The project took him six years. The navy built an enormous brick structure in its dockyard at Portsmouth to accommodate the armada of engines they knew was coming. And one by one, first from his workshop back up on London’s Margaret Street and then, as the company expanded, from a site in Lambeth, south of the River Thames, Maudslay’s epoch-making machines started to arrive.
There would be forty-three of them in total, each performing one or another of the sixteen separate tasks that transformed a felled elm tree into a pulley block to be sent to the naval warehouse. Each machine was built of iron, to keep it solid and sturdy and able to perform its allotted task with the kind of accuracy the navy contract demanded. So there were machines that sawed wood, that clamped wood, that morticed wood, that drilled holes and tinned pins of iron and polished surfaces and grooved and trimmed and scored and otherwise shaped and smoothed the blocks’ way to completion. A whole new vocabulary was suddenly born: there were ratchets and cams, shafts and shapers, bevels and worm gears, formers and crown wheels, coaxial drills and burnishing engines.
And all inside the Block Mills, as the structure was named in 1808, which was soon set to thundering activity. Each of Maudslay’s machines was sent power by ever-rotating and flapping leather belts, which themselves were spinning by their connection to long iron axles mounted to the ceiling and that, in turn, were set eventually rotating by an enormous thirty-two-horsepower Boulton and Watt steam engine that roared and steamed and smoked outside the building, in its own noisy and dangerous three-story lair.
The Block Mills still stand as testament to many things, most famously to the sheer perfection of each and every one of the hand-built iron machines housed inside. So well were they made—they were masterpieces, most modern engineers agree—that most were still working a century and a half later; the Royal Navy made its last pulley blocks in 1965. And the fact that many of the parts—the iron pins, for example—were all made by Maudslay and his workers to exactly the same dimensions meant that they were interchangeable, which had implications for the future of manufacturing more generally—as we shall soon see, when the concept of interchangeability was recognized by a future American president.
But the Block Mills are famous for another reason, one with profound social consequences. It was the first factory in the world to have been run entirely from the output of a steam engine. True, earlier machines had been driven by water, and so the concept of mechanization itself was not entirely new. But the scale and the might of what had been built in Portsmouth were different, and stemmed from a source of power not dependent on season or weather or on any external whim. Providing there was coal and water, and an engine made to specifications demanding of the greatest precision, the factory powered by it would run.
The saws and the morticing devices and the drills of the future would thus be powered by engines. These engines would (both here in Portsmouth and then very soon thereafter in a thousand other factories elsewhere, making other things by other means) no longer be turned and powered and manipulated by men. The workers who in their various wood shops had hitherto cut and assembled and finished the navy’s pulley blocks had now become the first victims of machinery’s cool indifference. Where more than a hundred skilled craftsmen had once worked, and had filled, just, the navy’s insatiable appetite, now this thundering factory could feed it with ease, without ever breaking a sweat: the Portsmouth Block Mills would turn out the required one hundred thirty thousand blocks each year, one finished block every minute of every working day, and yet it required a crew of just ten men to operate it.
Precision had created its first casualties. For these were men who needed no special skills. They did no more than feed logs into the slicing machine hoppers and, eventually, take the finished blocks away and stack them inside the storehouses; or else they took their oilcans and their bunches of cotton waste and set to greasing and lubricating and polishing and keeping a weather eye on the clanging and clattering maelstrom of black-and-green and brass-trimmed behemoths, all endlessly mocking them, by revolving and spinning and belching and rocking and lifting and splitting and sawing and drilling, an immense orchestra of machinery that was crammed into the massive new building.
The social consequences were immediate. On the plus side of the ledger, the machines were precise; the machines did accurate work. The Lords of the Admiralty declared themselves content. Brunel received a check for the money saved in one year: £17,093. Maudslay received £12,000 and the acclaim of the public and of the engineering fraternity and became generally regarded as one of the most important figures in the early days of precision engineering and one of the prime movers of the Industrial Revolution. The Royal Navy shipbuilding program would now go ahead as planned, and with the new squadrons and flotillas and fleets that were able to be created so swiftly, the British saw to it that the wars with France were duly ended, and to Britain’s advantage.
Napoleon* was finally defeated, and was shipped off to Saint Helena in exile, traveling aboard a seventy-four-gun third-rate ship of the line, the HMS Northumberland, with as escort the smaller sixth-rate twenty-gun HMS Myrmidon. The rigging and other rope work of these two vessels were secured with about sixteen hundred wooden pulley blocks, almost all of them made in the Portsmouth Block Mills, sawed and drilled and milled with Henry Maudslay’s iron engines, all operating under the supervision of ten unskilled navy contract workers.
Still, the ledger had two sides, and on the minus side, a hundred skilled Portsmouth men had been thrown out of work. One imagines that over the days and weeks after they were handed their final pay and told to go, they and their families wondered just why this had happened, why it was that as the need for products demonstrably increased, the need for workers to construct these products began to shrink swiftly away. To this scattering of Portsmouth men, and to those who relied upon these men for security and sustenance, a sum total rather too few for any serious political consideration, the arrival of precision was not altogether welcome. It seemed to benefit those with power; it was a troubling puzzlement to those without.
There was a social consequence, a reaction, although the best known, mainly because of its intermittent and spectacular violence, took place some hundreds of miles to the north of Portsmouth and was specifically involved in another industry altogether. Luddism, as it is known today, was a short-lived backlash—it started in the northern Midlands in 1811—against the mechanization of the textile industry, with stocking frames being destroyed and mobs of masked men breaking factories to stop the production of lace and other fine fabrics. The government of the day* was spooked, and briefly introduced the death penalty for anyone convicted of frame breaking; some seventy Luddites were hanged, though usually for breach of other laws against riot and criminal damage.
By 1816, the steam† had gone out of the rioters, and movement generally subsided. It never entirely died, though, and the word Luddite (from the movement’s presumed leader, Ned Ludd) remains very much in today’s lexicon, mainly as a pejorative term for anyone who resists the siren song of technology. That it does so serves as a reminder that, from its very beginnings, the world of precision-based engineering had social implications that were neither necessarily accepted nor welcomed by all. It had its critics and its Cassandras then; it has them still today, as we shall see.
Henry Maudslay was by no means done with inventing. Once his forty-three block-making machines were all thrumming along merrily down in Portsmouth, once his contract with the navy had been completed, once his reputation (“the creator of the industrial age”) was secure, he came up with two further contributions to the universe of intricacy and perfection. One of them was a concept, the other a device. Both are essentials, even at this remove of two centuries, the concept most especially so.
It involves the notion of flatness. It involves the notion that a surface may be created that is, as the Oxford English Dictionary has it, “without curvature, indentation or protuberance.” It involves the creation of a base from which all precise measurement and manufacture can be originated. For, as Maudslay realized, a machine tool can make an accurate machine only if the surface on which the tool is mounted is perfectly flat, is perfectly plane, exactly level, its geometry entirely exact.
An engineer’s need for a standard plane surface is much the same as a navigator’s need for a precise timekeeper, as John Harrison’s, or a surveyor’s need for a precise meridian, such as that drawn in Ohio in 1786 to start the proper mapping of the central United States. The more prosaic matter of the making of a perfectly flat surface, a critical part of the machine-made world, required only a little ingenuity and a sudden leap of intuition—both these gifts combining in the late eighteenth century in the workshop of Henry Maudslay.
The process is simplicity itself, and the logic behind it flawless. The Oxford English Dictionary illustrates it nicely with a quotation from the James Smith classic Panorama of Science and Art, first published in 1815, that “to grind one surface perfectly flat, it is … necessary to grind three at the same time.” While it has to be assumed that this basic principle had been known for centuries, it is commonly believed that Henry Maudslay was the first to put it into practice, and create thereby an engineering standard that exists to this day.
So accurate was Henry Maudslay’s bench micrometer that it was nicknamed “the Lord Chancellor,” as no one would dare have argued with it.
Photograph courtesy of the Science Museum Group Collection.
Three is the crucial number. You can take two steel plates and grind them and smooth them to what is believed to be perfect flatness—and then, by smearing each with a colored paste and rubbing the two surfaces together and seeing where the color rubs off and where it doesn’t, as at a dentist’s, an engineer can compare the flatness of one plate with that of the other. Yet this is a less than wholly useful comparison—there is no guarantee that they will both be perfectly flat, because the errors in one plate can be accommodated by errors in the other. Let us say that one plate is slightly convex, that it bulges out by a millimeter or so in its middle. It may well be that the other plate is concave in just the same place, and that the two plates then fit together neatly—giving the impression that the flatness of one is the same as the flatness of the other. Only by testing both these planes against a third, and by performing more grinding and planing and smoothing to remove all the high spots, can absolute flatness (with the kind of near-magical properties displayed by my father’s gauge blocks) be certain.
AND THEN THERE was the measuring machine, the micrometer. Henry Maudslay is generally also credited with making the first of this kind of instrument, most particularly one that had the look and feel of a modern device. In fairness, it must be said that a seventeenth-century astronomer, William Gascoigne, had already built a very different-looking instrument that did much the same thing. He had embedded a pair of calipers in the eyeglass of a telescope. With a fine-threaded screw, the user was able to close the needles around each side of the image of the celestial body (the moon, most often) as it appeared in the eyepiece. A quick calculation, involving the pitch of the screw in inches, the number of turns needed for the caliper to fully enclose the object, and the exact focal length of the telescope lens, would enable the viewer to work out the “size” of the moon in seconds of arc.
A bench micrometer, on the other hand, would measure the actual dimension of a physical object—which was exactly what Maudslay and his colleagues would need to do, time and again. They needed to be sure the components of the machines they were constructing would all fit together, would be made with exact tolerances, would be precise for each machine and accurate to the design standard.
As with Gascoigne’s invention of a century before, the bench micrometer’s measurement was based on the use of a long and skillfully made screw. It employed the basic principle of a lathe, except that instead of having a slide rest with cutting or boring tools mounted upon it, there would be two perfectly flat blocks, one attached to the headstock, the other to the tailstock, and with the gap between them opened or closed with a turn of the leadscrew.
And the width of that gap, and of any object that fitted snugly between the two flat blocks, could be measured—the more precisely if the leadscrew was itself made with consistency along its length, and the more accurately if the leadscrew was very finely cut and could advance the blocks toward one another slowly, in the tiniest increments of measurable movement.
Maudslay tested his own five-foot brass screw with his new micrometer and found it wanting: in some places, it had fifty threads to the inch; in others, fifty-one; elsewhere, forty-nine. Overall, the variations canceled one another out, and so it was useful as a leadscrew, but because Maudslay was so obsessive a perfectionist, he cut and recut it scores of times until, finally, it was deemed to be wholly without error, good and consistent all along its massive length.
The micrometer that performed all these measurements turned out to be so accurate and consistent that someone—Maudslay himself, perhaps, or one of his small army of employees—gave it a name: the Lord Chancellor. It was pure nineteenth-century drollery: no one would ever dare argue with or challenge the Lord Chancellor. It was a drily amusing way to suggest that Maudslay’s was the last word in precision: this invention of his could measure down to one one-thousandth of an inch and, according to some, maybe even one ten-thousandth of an inch: to a tolerance of 0.0001.
In fact, with the device’s newly consistent leadscrew sporting one hundred threads per inch, numbers hitherto undreamed of could be achieved. Indeed, according to the ever-enthusiastic colleague and engineer-writer James Nasmyth, who so worshipped Maudslay that he eventually wrote a rather too admiring biography, the fabled micrometer could probably measure with accuracy down to one one-millionth of an inch. This was a bit of a stretch. A more dispassionate analysis performed much later by the Science Museum in London goes no further than the claim of one ten-thousandth.
And this was only 1805. Things made and measured were only going to become more precise in the years ahead, and they would do so to a degree that Maudslay (for whom an abstraction, the ideal of precision, was perhaps the greatest of his inventions) and his colleagues could never have imagined. Yet there was some hesitancy. A short-lived hostility to machines—which is at least a part of what the Luddite movement represented, a mood of suspicion, of skepticism—briefly gave pause to some engineers and their customers.
And then there was that other familiar human failing, greed. It was greed that in the early part of the nineteenth century played some havoc with precision’s halting beginnings across the water, to where this story now is transferred, in America.
