judge the importance of a technological breakthrough is to examine how simple the problem seems in retrospect, after it is solved. We now accept the law of gravity, the theory of natural selection and evolution, the heliocentric model of the universe and scores of other technological and scientific breakthroughs without a thought about how difficult they were to develop because they seem so self-evidently true today. Indeed, it is difficult for us even to imagine what it would have been like to live in a world in which people conceived of the sun as going around the earth. The discovery of how to measure longitude accurately is another one of these highly significant technological breakthroughs that we now take entirely for granted even though it was an immensely difficult and complicated task. Dava Sobel's book Longitude: The True Story of a Lone Genius Who Solved the Greatest Scientific Problem of His Time along with the NOVA program "Lost at Sea: The Search for Longitude" remind us of the difficulty of meeting the particular technological challenge of how to determine longitude accurately. But more than that, these two works on the invention of navigational instruments help us understand in general the ways in which technological and scientific discoveries are brought about and how they are integrated into society to the point that they become entirely unremarkable. After examining Sobel's book and the NOVA program, this paper concludes by examining the how the mapping of the human genome is a scientific and technological breakthrough with important scientific, technological and cultural analogies to the discovery of the way to measure longitude.
Sobel's book and "Lost at Sea" both return us to the 18th century, a point in history in which latitude could be easily calculated but longitude was impossible to determine accurately. So important was this inability to determine longitude - most especially for those at sea - that the British government offered a prize to the first person able to deserve a technological answer to this burning navigational question and so keep Britain's ships (and thus her trade routes as well as her imperial designs) safe. The offered prize of 20,000 pounds was a fortune in its time.
Sobel's book focuses on John Harrison, who believed that the key to creating a highly accurate clock - or chronometer - was essential to allow those at sea to measure the longitude of their position.
For lack of a practical method of determining longitude, every great captain in the Age of Exploration became lost at sea despite the best available charts and compasses. From Vasco da Gama to Vasco Nunez de Balboa, from Ferdinand Magellan to Sir Francis Drake - they all got where they were going willy-nilly, by forces attributed to good luck or the grace of God.
Other inventors believed that more accurate stellar and lunar charts were the key to accurately measuring longitude. Sobel's book is in some ways the recounting of the contest not just amongst different individuals desirous of the acclaim and wealth that would accrue to the winner of the prize for discovering how to measure longitude but also a recounting of the struggle between two different ways of thinking. Both Sobel in her book and the contributors to the NOVA program (which of course includes comments by Sobel) suggest that Harrison was victorious not only because he was both smart and incredibly persistent but also because he was the most forward-thinking of those seeking to understand the technical problem of longitude. Those trying to come up with ever-more accurate stellar and lunar charts were in many ways clinging to the past: They were trying to fine-tune the ancient technology of navigating by the skies. Harrison, on the other hand, understood that any given technology can only be improved to a certain extent, and beyond that one has to develop an entirely new technology. This is what he set out to do.
Before examining Harrison's invention, we should take a moment to consider why it was that longitude was so difficult to measure to begin with. Sobel provides a compelling description of the difficulties involved:
Here lies the real, hard-core difference between latitude and longitude - between the superficial difference in line direction that any child can see: The zero-degree parallel of latitude is fixed by the laws of nature, while the zero-meridian of longitude shifts like the sands of time. This difference makes finding latitude child's play. And turns the determination of longitude, especially at sea, into an adult dilemma - one that stumped the wisest minds of the world for the better part of human history.
Harrison, who was self-trained as an inventor and as a clockmaker, became convinced that the technical key to the ability to measure longitude accurately was related to the ability to "know the time in two places at once."
However, knowing that the key to measuring longitude was a highly precise clock and actually constructing such an accurate timepiece are quite different things, and both the book and the NOVA program give us some real sense of the technological challenges faced by Harrison as he tried again and again to construct a clock that would not only be sufficiently accurate but that could maintain that level of accuracy on a ship with its humidity and constant motion.
There are enormous problems in trying to make a precision piece of clockwork performs accurately at sea. There's the humidity. There are changes in atmospheric pressure. There's different gravity and different latitudes. There are enormous variations in temperature, from the cold North Sea to the blazing suns of the Caribbean. These affect the materials out of which the timekeeper is made. And then, of course, the most obvious of all is the rocking of the ship, the tremendous shocks that the ship receives when it moves from one wave to the other. All these things made it virtually impossible for a timekeeper to keep time at sea, or so they though in the 18th century.
Harrison solved some of the technical problems of building a better clock because he addressed the problem in a different way than it had been addressed before, as the NOVA program notes. While others had worked on improvements in the metal parts of clocks as well as the lubricants used in those clocks, Harrison decided to try new kinds of woods. He looked at the problem of clock-making more as a carpenter would than in the way that a professionally trained horologist would, and his use of a different kind of wood was one of the improvements he made that led to his breakthroughs in measuring longitude.
Essential to the story as Sobel tells it is the social context of Harrison's work. His push for an accurate timepiece was never simply a question of gears. Rather, Sobel reminds us again and again that new technologies - especially ones that make major changes in society in the way that Harrison's invention did - are above all the result of new ways of thinking rather than simply improvements on existing tools. But just as important to change in human society as is the ability to think in new ways is the ability to overcome the resistance of those who are desperately clinging to old ways of seeing the world. Sobel makes it clear that Harrison's battle against the Board of Longitude (with its bias toward celestial navigation) was a far more difficult one in many ways than his battle against such natural enemies as friction.
We can see similar battles over new technologies being fought today. Just as Harrison was struggling to replace navigational dependence on the stars with the use of new ways of measuring time, the mapping of the human genome has allowed us to view human…