Thursday, 6 December 2012

Longitude by Dava Sobel

From The Week of November 26th, 2012

Though our world is, for the most part, advanced by slow and steady progress that is too esoteric and individually insignificant for humanity to recognize, there can be no doubt that there are colossal moments in the history of human knowledge which have spilled entire revolutions of thought and understanding. From the realization that the Earth is round to the discovery that there do not be dragons at the edges of the world, the revelations of individuals have reshaped the fortunes of kingdoms and continents, all while laying the groundwork for the discoveries to come. It is an awesome notion, to think that ones own genius may live on for centuries, long after ones own bones are dust. And yet, Copernicus and Galileo, Newton and Einstein are proof of its truth. It would be a shame to exclude John Harrison from this honored list. For, as Ms. Sobel demonstrates, he too changed the world.

For much of recorded history, accurately measuring longitude while at sea, or on the move generally, was maddeningly difficult. Compelled to rely upon flawed methods like Dead Reckoning -- using a previous known position to calculate direction and speed --, or Lunar Navigation -- measuring the moon against another celestial body --, voyagers were often profoundly mislead by their results. This practice proved particularly lethal at sea where accurately fixing ones position could mean the difference between striking land or starving at sea. In a world where journeying between continents was rare, this was a vexing problem only for that small subset of adventurers fixed upon the exploration of the globe. However, with the advent of widespread mercantile trade in the last 500 years, it became a problem of much greater societal import, leading to prizes being extended by various bodies for a proper solution.

Enter John Harrison. A self-taught watchmaker, he defied conventional wisdom, that the longitude problem would be solved through an improved understanding of astronomy, and endeavored, instead, to rectify it through the proper keeping of time. For if a captain could set a ship-board clock to local time at the beginning of their voyage, and trust that said clock could keep accurate time through the whole of their journey, then they could compare local time with high noon wherever they were in the world and use the difference between the two to calculate their distance from home. On paper, this seems a simple enough problem, but how could someone in the 18th century create a clock whose mechanisms for time-keeping would be perfectly immune against storms and waves, dryness and humidity, vibrations and oscillations? Through trial and error, across decades of effort, Mr. Harrison sought to make such a perfect clock. His efforts would prove to be as successful as they were underappreciated.

From the exploits of the Harrisons to the shameful machinations of those who sought to deny them credit, Longitude is a brief but delightful contemplation of what, today, is a trivial pursuit. Not so 300 years ago, when life and death rode on knowing where one was in relation to the world around one. Ms. Sobel demonstrates how Mr. Harrison's solution to this problem was as brilliant as it was poorly received by the brightest minds of his day, their biases leading them to throw in his path every roadblock, every impediment to the achievement of his proper recognition. Professional jealousy veritably drips from these 150 pages, the envy of frustrated men coming to naught in the face of a fix far to clever for them. Ms. Sobel's account of this most interesting historical development is lovely but for its length. Devoted to keeping her work brief, her biography of john Harrison and his time necessarily suffers, curtailed far too much for this reader's liking. Certainly, it is better, especially with non-fiction, to err on the side of brevity over long-windedness, but there's brevity and then there's Longitude which seems, at times, like a rushed tour of something great and yet half-hidden from view, its mysteries left to the sands of time. I was left eager for more, both of Harrison himself and his competitors and foes. But alas, such knowledge will have to come from other sources.

Fine work... Ms. Sobel invariably delivers with her micro histories and Longitude is no exception. However, look not here for the whole story. That must be found in weightier volumes. (3/5 Stars)

No comments:

Post a Comment