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valkyrie_rider
·Earlier this year I got from Amazon the book titled "Longitude: the true story of the genius that solved the greatest scientific problem of this time" by Dava Sobel.
It tells the story of John Harrison's watches (he was recently featured in a Google doodle, check: https://en.wikipedia.org/wiki/John_Harrison) and how they solved the practical and strategic problem of calculating the Longitude of ships back in the 18th century.
The book is literally a page turner: I started reading it in a Friday 22:00 and finished around 2:00 (with a few breaks for tea and looking in wikipedia for further information on a few of the mentioned historical figures).
After a terrible ship wreck that costed the lives of over 5000 soldiers, England's parliament offered a 20,000 pounds prize to whoever solved the problem of longitude calculation in 1714.
Harrison was a carpenter who self-learned watchmaking and worked for 30 years to make a watch that could resist the challenges of travelling in high latitudes facing changes in temperature while keeping a precision of less than 3s gain/loss per day (the book explains how anything less precise would yield a big longitude positioning error).
He presented to the Longitude Board (that had scientists like Isaac Newton in his ranks) a series of watches (H1, H2, H3) that were improvements in both precision and size/weight, building up to his master piece the H4:
The H4 took 6 years to construct and made his maiden journey aboard the 50-gun HMS Deptford from London to Jamaica under the care of Harrison's younger son William in 1761. After the 81 days of journey, the watch allowed the longitude calculation with an approximate precision of one nautical mile.
A clear winner, right? Well, the Greenwich astronomers that were part of the board didn't think so and would make more requirements and give Harrison years of trouble for him finally being able to receive (part) of the prize, only after interference by the King George.
I won't provide further spoilers, but this is a story that is really fascinating and worthy learning more (both from a historical point of view as also for anyone that appreciate mechanical watches).
It tells the story of John Harrison's watches (he was recently featured in a Google doodle, check: https://en.wikipedia.org/wiki/John_Harrison) and how they solved the practical and strategic problem of calculating the Longitude of ships back in the 18th century.
The book is literally a page turner: I started reading it in a Friday 22:00 and finished around 2:00 (with a few breaks for tea and looking in wikipedia for further information on a few of the mentioned historical figures).
After a terrible ship wreck that costed the lives of over 5000 soldiers, England's parliament offered a 20,000 pounds prize to whoever solved the problem of longitude calculation in 1714.
Harrison was a carpenter who self-learned watchmaking and worked for 30 years to make a watch that could resist the challenges of travelling in high latitudes facing changes in temperature while keeping a precision of less than 3s gain/loss per day (the book explains how anything less precise would yield a big longitude positioning error).
He presented to the Longitude Board (that had scientists like Isaac Newton in his ranks) a series of watches (H1, H2, H3) that were improvements in both precision and size/weight, building up to his master piece the H4:
The H4 took 6 years to construct and made his maiden journey aboard the 50-gun HMS Deptford from London to Jamaica under the care of Harrison's younger son William in 1761. After the 81 days of journey, the watch allowed the longitude calculation with an approximate precision of one nautical mile.
A clear winner, right? Well, the Greenwich astronomers that were part of the board didn't think so and would make more requirements and give Harrison years of trouble for him finally being able to receive (part) of the prize, only after interference by the King George.
I won't provide further spoilers, but this is a story that is really fascinating and worthy learning more (both from a historical point of view as also for anyone that appreciate mechanical watches).
