Lessons From the Past: Longitude and the BP Oil Spill (part 1)

What parallels, if any can be drawn from history and brought to light with relevance to our current predicament. I speak of the BP oil spill now ravaging the Gulf of Mexico; a problem seemingly with little in the way of an obvious solution, and even less in the way of hope for the unlucky wildlife entrenched in the muck. This is without even mentioning the far-reaching economic consequences that are sure to follow such a catastrophe. BP and the authorities involved have tried various solutions, all for naught at this point, with the recent temporary remedy of collecting the oil by siphoning it into boats on the water’s surface. This is, of course, a “band-aid” solution at best, and BP knows it. With this in mind, they have turned their search for a definite solution outwards and have started asking the public at large for any assistance they might be able to offer. When I first heard this I was both irritated and astounded. How could they just give up? If they could not figure it out, what hope would anyone on Facebook have of coming up with an original, practicable solution? Ridiculous! Or is it?

I have recently begun reading Longitude by Dava Sobel. In her book, she details the quest to discover a workable means for assessing an ocean-going vessel’s longitude at sea. This necessary measurement, though commonplace and an afterthought today, was all but impossible in the early 18th century. Why? I mean, they had magnetic compasses and could measure their latitude using only a sextant and the heavens, so why was the accurate measurement of longitude so elusive? The answer is clearly described by Sobel, who states that the measurement of longitude is tempered by time. In other words, and very much unlike latitude, measuring longitude accurately requires that the persons aboard the vessels know their current time (in whatever timezone they might be in) and also the time at a specific place of known longitude (say their home port) at that very point in time. By knowing these, the sailor can deduce the number of hours difference and pinpoint his longitude. We must use a bit of math to make this clear (hold back the nausea). If the earth spins a full 360 degrees in a 24 hour period, then dividing that number (360) by 24 gives us the number of degrees longitude that’s equivalent to one hour. This number is thus 15 degrees. So by having the two clocks and measuring say, a 3 hour difference in time, we could then know that that ship is 45 degrees to the east or west of the point of reference. Make sense? Of course it does, your a bright person! We do, however, run into a snag at this point. You see, unlike latitude, longitude does not stay a constant as we travel vertically (north to south) on the globe. In other words, since the Earth is a sphere, the lines of longitude converge as you come closer to the poles, causing one to lapse many degrees of longitude in a relatively short amount of time. As an aside, it was this fact that contributed to the innate difficulty in steering and navigating ships with accuracy at the poles, despite the use of ever more advanced compasses and equipment, for many centuries and thus postponing mankind’s ability to explore these areas with ease.
It is plain that having two clocks is absolutely necessary with respect to accurate ascertainment of longitude. As Sobel points out, a pair of wristwatches would suffice. An object so commonplace and almost an afterthought in this time was, at one point, the thing of legends. There were certainly clocks in use during the early 18th century, however, they were hardly as accurate as those now in use and often lost a number of minutes per day. Winding a clock every so often was absolutely commonplace, making it imaginable that utilizing these devices at sea might prove troubling. There was also the problem of the elements at sea. Clocks were temperamental where changes in climate were concerned. Heat would cause their internal parts to expand and the lubrication liquid to thin out, while cold would do the opposite and cause the metal to contract and the oil to congeal. The tossing and pitching of the boat would also cause the clock to often speed up, slow down, or completely stop. Even something as delicate as changes in the Earth’s gravity at certain latitudes might cause disturbances. Researchers toiled at finding a workable solution to this problem while many sailors, even some who were excellent navigators in their own right, were lost at sea.
Sobel gives the example from of Admiral Sir Clowdisley Shovell who, upon returning home in October, 1707 after proving victorious in skirmishes against the French forces in the Mediterranean Sea, was overcome by a fog that clouded his ability to navigate near the treacherous, rocky coast of Brittany. His navigators (keep in mind they had no way of assessing their longitude) judged their craft to be safely west of this coast. Much to their astonishment and horror, they had misjudged their longitude and were actually in the midst of the Isles of Scilly. The Isles form an archipelago off the southwestern tip of Great Britain, and those rocky waters tore their ships to shreds. Shovell’s flagship, the Association, was the first to strike the rocks and sink in short order; the Eagle and the Romney followed quickly behind. In total, four of the five ships in the small fleet met their ends. Miraculously, Shovell managed to wash up on shore; shaken to his very bones, but very much alive. In a strange twist of fate however, a starving and desperate woman combing the beach came upon his body and quickly noticed the rather large emerald ring on his finger. In his depleted state, she managed to murder him and steal the ring. She confessed her crime on her deathbed 30 years later (Sobel, 1995, pg. 11-13). Apparently, luck runs out for us all, though some quicker than others. Many other stories like Sir Clowdisley’s (minus the murder) made it all to apparent that an answer to the “longitude question” must be answered, and quickly.