Longitude

Like Gutenberg, and unlike some of the other self-taught inventive geniuses who spring to mind (like Franklin, Edison and Tesla), John Harrison was not a catholic inventor: his speciality was time. He did, though, draw from the fields of metallurgy, cabinetry and mechanics to find unconventional materials and techniques, and with what can be seen either as impossible optimism or sheer stubbornesss, Harrison managed to solve a problem which had killed thousands of his countrymen. By applying and extending the time-keeping technology of his time, he invented a means by which ships at sea could reliably determine their own longitude, and the story of how he did it ranks with any of the great dramas of science. Dava Sobel tells that story in Longitude: The True Story of a Lone Genius Who Solved the Greatest Scientific Problem of His Time.

Longitude author Dava Sobel pages 184 publisher Penguin rating 8.5 reviewer timothy ISBN 0140258795 summary Inventive genius rethinks the calculation of time and revolutionizes navigation.

A vexing problem, a golden fleece Specifically, from the age of around 30 (though Sobel points out that the time of his birth is only known within a few years), Harrison devised a series of time-keeping devices designed to keep time with accuracy orders of magnitude more accurate than the water, spring and pendulum-driven clocks of the day. The ferocity and diligence with which he wore down the technical gremlins conspiring to throw clocks off by seconds or minutes a day demonstrates a personal dedication as intense as those of the Las Alamos scientists laboring to forge the atomic bomb. Like those men, Harrison had something else in mind besides the joy of invention -- he was determined to win a prize which in modern money would mean millions of dollars, not to mention the prestige of royal recognition.

That prize (in the amount of 20,000 pounds) was set forth in a 1714 act of Parliament for anyone who could provide a practical method for ships at sea to determine their latitude to within half a degree.

With a clear sky and a sextant, finding latitude is relatively easy. Once it was widely accepted that the earth was a globe spinning about an axis perpindicular to the equator, the rest was (to our modern viewpoint) a piece of cake: locate a star (Polaris, at least in the Northern Hemisphere) which approximates an extension of that axis of spin, note the apparent angle from an observer's horizon, and perform some simple trigonometry. The problem with finding longitude is that no such simple trick exists.

By constructing elaborate star charts which correlate observed lunar and stellar positions, it was hypothesized (and eventually demonstrated in practice) that longitude could be determined using a complicated process of observing the sky (only at night, and only on a clear enough night to observe, of course), then comparing the stellar observations with a log of previous observations compiled by astronomers over a lunar-orbit cycle of 18 years. Though cumbersome, the amazine thing is that enough observations were compiled for this method of longitude determination to not only catch on, but for the charts to remain in continuous repair and revision until 1907. So desperate were navigators of the time to know where on the globe they sailed, even this tricky means was better than none at all.

Earthly contention A deftly-woven substory -- and perhaps really the main story -- is of the rivalry between the astronomers and the clockmakers, both in general and specifically in the case of Harrison and the man who turns out to be in parts both his competitor and his his judge, astronomer Nevil Maskelyne. For the early years of the race for a longitude method, the star-watchers held favor, as their methods were seen as purer and more reliable than those of the craftsmen whose tiny mechanisms were subject to mishandling as well as corrosion and other seagoing inevitabilities. Of all the entrants in this high-stakes race, Maske and Harrison represented probably the best (or at least the best-positioned) of each camp, so their struggles and the eventual outcome are particularly significant.

The culmination of Harrison's work came after 4 generations of refinement, a pocket-sized device, the appearance of which is at once antique and surprisingly modern. And (what should come no surprise), the Harrison chronometer keep startlingly accurate time -- good enough to comfortably meet the requirements of sought-after practicable longitude system. For reasons that make the book worth reading, collecting on that prize was anything but simple.

Reactions: As I read this book on the subway, I found myself nodding and grinning, and at times frowning obediently at the evil-landlord melodrama of Harrison vs. Maskelyne. The story of the unschooled inventor toppling the expectations and machinations of a well-connected science establishment isn't just interesting -- it's positively inspiring. It's hard not to know the eventual outcome just a few pages in, but Sobel keeps the story interesting by loosing the particulars slowly, revealing in turn setbacks and triumphs.

Though Sobel doesn't address this issue explicitly, the magnitude of the longitude prize and the thoroughly bureaucratic, arbitrary behavior of at least some of its keepers also raise the issue of state-funded science in general, and made me think of the moon race, mass immunizations and and everyone's favorite giant global network, no matter who invented it.

Longitude is also interesting for what it says about the transfer of information and ideas (if not technolgy itself) which went on in the time before today's Information Age.

Some more praise dressed up as complaint: The only gripe I have with this book is hardly fair, given it's brevity. But here it is: a few pages of illustrations and more detailed annotations (even an associated Web site) would make the book as much a starting point as a destination. While the reader-friendly avoidance of picayune detail is probably a wise compromise -- I know I appreciated it!, I do wish the book had a few pages at least of additional technical information. The glossy illustrations on and inside the front cover are some consolation at least, since they're good photographs (if small) on a nice glossy surface. That such an ommision is noticeable speaks well of this book -- most books leave me wishing they were shorter, not longer.

You can order this book from ThinkGeek.

Comments

Re:Nit

[Kotetsu]

Actually, no it isn't. To quote from Webster's Collegiate Dictionary:

catholic 1: Comprehensive; Universal; broad in sympathies, tastes or interests

For once, a Slashdot editor does something literate and he gets flamed for it by those who miss it. BTW - I'm replying to your post because your the only one who obthered to log in. Why waste time replying to AC's.

John Harrison: 1st Open Source Inventor?

[multipartmixed]

You can read more about John Harrison here.

Anyhow, to make a long story short, I found it interesting that the British government required him to explain the workings of H4 to a panel of scientists (etc) in order to pass the knowledge of how it worked on to the public.

The article I've quoted mentions that his endowment made him the first recepient of a government research grant -- and the government had the sense to make sure he published the inner workings before paying him.

--

Re:Eh?

[MikeBabcock]

Catholicism, the religion, is indeed capitalised. The name "Catholic" was chosen by the Catholic Church because it meant "universal". They were thus stating "We are the universal Church".

The word catholic, on the other hand, is just a word that means universal or complete.