(Published as the cover review in the Contemporary sometime in 2000)
I stole my first screwdriver from my grandfather when I was seven. We had been using it in the assembly of an Guillow wooden airplane (a Sopwith Camel), although how we had been using it escapes me, as I remember lathering the press-cut balsa pieces with sour-smelling Elmer’s dope. The screwdriver was squat, the handle pear-shaped and worn paintless to the stem where a blotch of deep brown circled the metal. The broad flat blade made up fully half the tool’s metal length.
I never used the stolen screwdriver. Thankfully, it was too wide to reach the recessed screws of my alarm clock, which soon fell victim to a hammer anyway. I remember, though, clutching the squat screwdriver, pressing the handle against my palm with outstretched fingers as I lay in bed at night listening to public radio.
For the next seven years, screwdrivers proliferated: a set from my mother, Craftsman, with blue and translucent yellow plastic handles; from my father’s tool cabinet chipped black-handled mongrels, paint-spattered and nicked round at the blades; sets and sets of miniatures, each asking the impossible of dexterity in the demolition of all unfortunately unscrewable electrical appliances; and the prized, if seldom-used, oddities – those of socket and square head, of absurdly-long shaft, or of other difference.
All these gradually migrated from our basement workshop into my bedroom, littering the floor amongst pieces of the partially dissembled. Some screwdriver was the key to any material curiosity; even screwless gewgaws could be pried apart with a levered thin flathead or, barring that, carefully smashed with one of the larger specimens.
Of all the hand tools of my youth, the screwdriver, in my hand, was the most destructive and, perhaps for that reason, the most pleasing. It was the most natural, transforming easily-given torque into linear force via threads effortlessly, thoughtlessly, or just gouging and bludgeoning.
The driver is as integral a part of any toolbox as a handsaw, plumber’s (or mechanic’s) wrench, pair of pliers, hammer, and drill. It is timeless, a design so simple as to defy invention. Yet unlike the others, the screwdriver (and, to a lesser extent, its counterpart, the screw) are of recent origin.
Hence essayist Witold Rybczynski’s interest in unraveling the anomaly of the screwdriver’s origin. His One Good Turn: A Natural History of the Screwdriver and the Screw originated as a New York Times Magazine article on “the best tool of the millennium.” Although Rybczynski initially wandered far from the toolbox (eyeglasses were his first choice, having been invented in the late 13th century), Magazine editor David Shipley, familiar with Rybczynski’s The Most Beautiful Home in the World, a book reminiscent of James Burke’s Connections in the loosely-connected tendrils that it draws from Rybczynski’s building of his own home, insisted on a stricter definition of tool. Shipley suggested that The Most Beautiful Home might make a good starting point. Rybczynski swallowed his disappointment and pressed on.
The choice of a best tool isn’t obvious. Rybczynski discounts power tools: their results “no different” than if a hand-tool had been used. “Increasing the productivity of carpenters does not seem to me in the same category as the invention of entirely new devices.” So then which hand tool? Rybczynski divides his tools into four classes: measurement, cutting and shaping, hammering, and drilling.
Quick research reveals that the basic tools of measurement predate the first millennium. Cutting and shaping tools are also disqualified: saws and chisels are of similar age as measures and levels. The Romans invented the plane. Hammers, likewise, are right out. Even improvements, such as the claw head, date back to ancient Rome’s forges. Finally, the drill, in bow-form, close cousin of fire-stick, has been attributed to the ancient Egyptians. The Romans claim the auger, hardly an interesting tool, and the brace, though likely of medieval European origin, has been largely supplanted in modern woodworking by equipment of wholly dissimilar (it’s so-interesting use in trephination notwithstanding).
With no topic and cursing the Romans, Rybczynski consults his wife. “Wherever I’ve lived I’ve always had a screwdriver in the kitchen drawer,” she says. “You always need a screwdriver for something.” Rybczynski is skeptical.
Still, he consults his library. Both Goodman’s History of Woodworking Tools and the Encyclopedia Britannica date the screwdriver to the Nineteenth century. Something’s up.
Rybczynski, searching standard references and tool histories, finds references to screws as early as 1750, but the earliest reference to the screwdriver he can find is 1779. Until, that is, Raphael Salaman’s Dictionary of Tools tips him off to an alternate naming: turnscrew, a literal translation of the French tournevis. Could the screwdriver be a French invention?
A 1772 French encyclopedia leads him off-track: the illustrated tournevis is a flat-bitted brace—the first screwdriver? Diderot and d’Alembert’s Encyclopédie, of 1765, illustrates a “short-bladed tool with a flat, oval wooden handle,” essentially “an ordinary modern screwdriver.” Was the screwdriver born full-grown?
Rybczynski shifts his focus to the screw, for the chance that it may be pictured or named in mid-millennium technical treatises. Almost immediately, this lark pays off: Agostino Ramelli’s Rube Goldberg-esque Le diverse et artificiose machine, published in Paris in 1588, includes plans for a hand-cranked flour mill, held to its wooden base with slotted screws.
A Dürer etching of 1518, of a cannon—but, alas, with no screws—leads Rybczynski in another direction: weaponry, the spur of technological development. A type of early French gun, called the petronel, used a matchlock, secured to the stock with screws, as nails would have loosened from the vibration of repeated firing. The match-locked petronel, quickly succeeded wheel-locked models, dates to the mid fifteenth century.
So what held the screwdriver up from popular use for at least 300 years? Although Rybczynski waffles on the premise, the screw, and not its driver, is the likely culprit. Early screws were difficult to manufacture and expensive. Their threads were filed by hand, both laborious and notoriously inaccurate. “The quality was also exceedingly bad, it being impossible to produce a well-cut thread by such means,” writes Joseph Chamberlain in his “Manufacture of Iron Wood Screws.”
Job and William Wyatt, of Staffordshire, England, patented the first mechanical screw manufacturing process in 1760 but were unable to commercialize their developments until 1776, converting a Birmingham corn-mill into what Rybczynski identifies as “the world’s first screw factory.” The business quickly failed.
The popularity of butt hinges for doors, though, drove demand for screws, necessary for the attachment of the hinges to the door as nails could not be clenched within the butt of the door and would quickly work loose. Capitalizing on the butt-hinge, new owner’s of the Wyatt’s factory finally brought manufactured screws successfully to market, for the first time selling regularly threaded screws at bulk prices.
Still, early manufactured screws had a damning deficiency: no means had yet been invented to taper the screw’s thread to its point. In fact, early manufactured screws were blunt, requiring a lead hole. The tapered thread was to be the first contribution of American ingenuity to the production of screws.
Patents issued in the 1830s and 1840s cemented Providence, Rhode Island, as the center of world screw production. Both Cullen Whipple and Thomas Sloan invented methods of tapering a screw’s thread to a point. Charles Rogers patented a method of tapering the thread to the screw’s core, towards the head. Whipple also devised an automatic machine for the production of screws, a replacement for the three or more machines required previously, thoroughly mechanizing the process. The American Screw Company and its Providence competitors grew to become the behemoths of screw manufacturing.
The screw would evolve further still. According to Canadian inventor Peter L. Robertson, “The big fortunes are in small inventions.” And Robertson’s invention was among the smaller, least-complicated of its time: the Robertson socket-head screw. “This is considered by many,” he wrote, “as the biggest little invention of the 20th century so far. Writing only seven years into the century, Robertson may well have been right.
The Robertson design was revolutionary: screws had always been slotted or polygonally headed—square or octagonal. Only slotted screws, though, could be countersunk, but slots, so easy to manufacture, brought with them three major problems: slotted screws needed to be held to screwdrivers (by hand, magnetic contraption, or otherwise) and guided explicitly; slipping was always a danger; and cam-out, the stripping of the screw’s head, was becoming more and more of a problem with automated screw-driving machinery, particularly in the manufacture of automobiles.
Hence Robertson’s genius: a recess, “square with chamfered edges, slightly tapering sides, and a pyramidal bottom.” Robertson’s genius, though, met its match in his arrogance. Refusing to license his design to Henry Ford, among other eager industrialists, Robertson doomed himself to a life of footnotability. Except in Canada and among certain craftsmen, the Robertson socket is unknown. His screw, however, sparked an explosion of derivatives.
Rybczynski’s research uncovered more than twenty American patents in 1936 alone for improved screwdrivers. Included in these were several to a middle-aged Oregonian, Henry F. Phillips, father of the Phillips head. Phillips’s design improved over Robertson’s in two interesting ways: first, the Phillips-headed screw could be driven effectively by a conventional screwdriver—an early stab at backwards-compatibility. Second, and surprisingly, Phillips screws, as anyone who’s used one knows, invariably cam-out as torque increases. While frustrating to the woodworker, high-torque cam-out was a benefit to the automobile industry, which could now rely on the screw, instead of precision manufacturing equipment, to prevent over-screwing and head twist-offs.
So, despite its relatively recent adoption, the screwdriver may still have been intuitively obvious, beyond invention, likely born in its present form. Even the basic shape of the screw, a helix, has a long history dating back at least to ancient Greece: Hero’s invention of the screw-press, as recorded early in the first millennium by Pliny. But screws were mostly impractical until the development of industrial machinery. The causality therein, however, gets complicated, as so much machinery uses screws, in the forms of lathes, presses, cams, and, of course, regular screws. Industrialization would have been impossible without the precisely machined screw, and vice-versa: the two are inseparably bound.
The screwdriver is simple if pleasing. But it’s the driver’s humble brother, the screw, which was the real workhorse of the last millennium. The screwdriver is a compromise, between a tool upon which must be born down, like the awl, and one that must be twisted. The fit in the hand of a screwdriver is deceptive once one actually begins screwing—given time, the driver tires, then blisters, then callusses the hand.
What a screwdriver can attach in seconds, the screw will hold forever, or, at least until it’s so-easily disengaged. In elegance, the screw is everything the nail is not: gently tapered on both ends, carefully machine-finished, precision-cut to unimaginable standards (those standards measurable with another screw: the micrometer), and able to be installed or removed nearly effortlessly.
Witold, how could you come so close and still miss the metallic gleam before your eyes: the screw, itself so simple and its development so complex.
Post a Comment