Exactly

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 headstock holds the spinning workpiece securely, and the slide rest that holds the tools that cut or chamfer or make holes in it moves longitudinally, pushed or pulled by the leadscrew, or transversely or in any other directions, along its path of travel.

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 from 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 Eastern White 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 down. 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 fast-moving and flapping leather belts, which were set to speeding 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 the 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.