Longitude: The True Story of a Lone Genius Who Solved the Greatest Scientific Problem of His Time.

Dava Sobel Walker & Co., $19 By Gregg Easterbrook 

Writers have long been fascinated with the centuries of effort required to devise reliable clocks, and the attendant imposition of notions like "standard" time and the time-regulated workday. The recent intellectual fashion has been to depict the development of accurate timepieces not as a convenience, but as part of the plot to divest people of their mystic connection to the pretechnological rhythms of nature by substituting a regimented clock-consciousness that served the interests of the lords of commerce. Probably the best expression of this view is Ronald Wright's beguiling 1991 book Time Among the Maya, which implausibly, if captivatingly, depicts ancient Mayan culture as more human than Ours because the Mayans believed time was not linear (tick...tick...tick) but in some vague fashion "circular" (tick ... retick ... tick). In postmodern theory, the progression from timekeeping based on sundials to giant pendulums to water engines with thousands of pieces to cheap digital devices with no moving parts is one long horror story. [Not that any intellectual would want to be late to a symposium to enounce this view.]

Yet as science writer Dava Sobel points out in her engaging and delightful new book Longitude, the big breakthroughs in clock construction came in pursuit of seafaring, not social regulation. In the 15th century, when nations began to sail the world's oceans seriously, the greatest obstacle to navigation was the inability to determine longitude (position east-west) at sea. Latitude (position north-south) could be read by observing the apparent motion of the sun. But this technique did not apply to longitude, and as a result the fleets of Europe spent inordinate time and incurred constant loss of life essentially wandering the high seas, trying to figure out where they were.

Minds as famed as Galileo, Newton, and Halley applied themselves to the problem and believed its solution lay in observation of the moon or the satellites of Jupiter. Sobel's tale concerns John Harrison, an obscure English watchmaker from a merchant-class background who believed clocks held the answer. Harrison had to battle the budding English science establishment, which wanted the solution to be based on the glamorous, aristocratic pursuit of astronomy, not the tinkerings of a mere craftsman. Sobel's story is rich with fascinating details both of scientific investigation and the bureaucratic politics of 18th-century England. Longitude is well-timed too, as the new Umberto Eco novel The Island of the Day Before features a protagonist marooned on an 18th-century vessel stocked with bizarre longitude instruments.

Serious pursuit of a means of fixing longitude began in 1707, after four British frigates ran aground in fog near their home port owing to total east-west disorientation, with the loss of nearly 2,000 men. Sobel recounts, in a horrifying passage, how after the vessels became lost in a week-long mist, a sailor approached Admiral Sir Clowdisley Shovell to declare that a private navigational logbook he had been keeping indicated the squadron was about to founder on the dangerous rocks of Scilly Isles southwest of England. British fleet rules then forbade any study of navigation by non-officers, because navigators had a wizard's status no enlisted personnel were allowed to challenge. Sir Clowdisley immediately had the sailor hanged for questioning the judgement of an Officer. Shortly afterward, his flagship plowed into the Scilly rocks, the three following ships faithfully smashing in as well.

Sadly, Sobel does not know the name of this lost sailor, who seemingly hit upon a significant idea and might himself have become an important figure had he not lived in a society that discriminated ruthlessly against the low-born. At any rate, the English government's response to the event was not to redress the outrage of executing a common man for telling an officer the truth, but to create a new bureaucracy--the Board of Longitude, which was to supervise research and award a prize of [pounds]20,000 (equivalent then to $12 million now) for the first reliable means of longitude fixation. In a manner that Washington Monthly readers are likely to find hauntingly familiar, die Board served mainly to suppress the most promising inventions, channel funds to the politically favored, and then remained in existence for 50 years after the problem of longitude was solved.

Harrison, an odd, reclusive man, proceeded on the assumption that a highly accurate clock would crack the nut. If a clock could show precisely the moment of noon at a ship's home port and sightings of the sun were employed at sea to determine the local noon, differences between the two could be employed to determine degrees east or west, roughly by calculating how many time zones the ship had passed through. This idea was generally known in the 18th century, but most scientists assumed clocks could never be made reliable enough for the task. Pocket watches of die era gave only an approximation of the hour; even vast clock-tower assemblies had to be readjusted daily. Friction between knurled parts, humidity changes, and the rolling of vessels at sea wiped out the accuracy of aH navigation clocks the navies of the Renaissance attempted to build.

Undeterred, Harrison spent his entire adult life locked away in a modest workshop pursuing an accurate clock, abandoning the pendulum in favor of gears. By 1722, he had produced a remarkably low-friction tower clock for an English manor house: The clock has now run continuously for more than 250 years. From 1737 to 1759, Harrison built three fantastic-looking naval chronometers, devices the size of desks that contained hundreds of gears and thousands of hours worth of intricate metalwork. Sent to sea on a trial, one of the clocks allowed nearly perfect longitude readings. But Harrison's attempt to claim the longitude prize was denied, as factions of die Board tried to channel the prize money to favorites. The Board kept stipulating that Harrison's clocks pass tests more strict than required in the original prize definition, while reducing the test requirements on solutions proposed by aristocrats.

In 1760, Harrison produced a device as revolutionary in its time as the silicon chip has been in ours--namely, the first timepiece to bear the name watch. A fraction of the size or cost of his previous inventions, the watch kept near perfect time no matter how harshly it was bounced around. The success of this British invention in enabling accurate timekeeping at sea is a reason the English were able to enforce establishment of zero longitude as passing through the old Royal Observatory on the Thames River town of Greenwich, and to deem Greenwich Mean Time the world's basis for time accounting.

For Harrison, the invention of the watch led to an incessant, Dickensian legal case over attempts to claim the longitude prize. By 1773, Harrison was 80, in failing health, and still not the recipient of the award, which the Board of Longitude steadfastly refused to confer upon him, in order to justify its previous resistance to timekeeping over astronomy. George III developed an interest in Harrison's cause; yet even the king was unable to make the Board of Longitude waver. Finally, Parliament bestowed a cash prize and deed of thanks on Harrison directly, so at least the inventor died with the knowledge of his vindication. The Board of Longitude was so incensed by this challenge to its authority that ultimately it never awarded the original [pounds]20,000 to anyone. When the HMS Beagle set sail in 1831, its intended purpose to map the longitude of Pacific islands, its primary equipment a complement of 22 chronometers, the Board of Longitude was still in existence, still arguing about who should have gotten its prize in the previous century. Gregg Easterbrook is a contributing editor of The Atlantic Monthly and author of the recent A Moment on the Earth.