Spanish get Harrison's longitude chronometer H2

Hi! I just saw this on the Wiki page for John Harrison, the horologist who invented the chronometer:

Harrison moved on to develop H2[7], a more compact and rugged version. In 1741, after three years of building and two of on-land testing, H2 was ready, but by then Britain was at war with Spain in the War of Austrian Succession and the mechanism was deemed too important to risk falling into Spanish hands.

Suppose the British decide to test the chronometer anyway, thinking that its ability to provide accurate longitude calculations (assuming it works) could be an asset to fighting the Spanish and closing in on Spanish ports. It is placed on a warship with instructions on how to operate it (in encrypted English) and the captain is ordered to destroy it rather than let it fall into Spanish hands. Harrison is left in England and will be issued reports on how well H2 is doing.

Well, the Spanish attack the ship, shoot a cannonball into captain's quarters, and kill the captain before he can destroy the machine. They then board the ship and walk away with the machine. They assume it is some kind of fancy clock and take it home as booty. Eventually, they realize it's a marine chronometer and find that they can use it for longitude calculations (though they don't realize how accurate it is at first).

The net result is the Spanish have H2 and the British have H1 (which is still under development). H3 is still under development.

Assume that both H1 and H2 provide longitude values with double the error range of H4 (the oversized pocket watch that won the longitude prize). Harrison didn't like H2 all that much, but second-rate to him would likely be first-rate to anyone else.
 
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Of course having an example of the technology would allow them to instantly divine the production methods :rolleyes:.

Seriously, machiens back then generally required their developer to be around to tell you exactly what he did in order to produce a copy, especially such stuff like Harrisons bearings and bimetallic strips.
 
Of course having an example of the technology would allow them to instantly divine the production methods :rolleyes:.
It's at least a good place to start, and the OP seems to indicate that it takes a while for the Spaniards to even figure out what it is, much less how to rebuild it. It's not like the question's about Confederates trying to replicate AK-47s.
 
It's at least a good place to start...


No, it isn't and spending a few seconds on the Wiki page the OP referenced would have explained that to you. The H2 design was a developmental dead end which Harrison abandoned after he realized there were fatal design flaws.

As for H2 begin "rugged" and "compact", it's only those things relative to H1. The device was roughly the size of a picnic cooler.

As Dava Sobel neatly explains in her book Longitude - a book I cannot recommend more strongly to anyone wanting to understand how invention, design, and development occur outside of a video game - Harrison's first three chronometers were actually developmental dead ends. While H1, H2, and H3 proved the concept of using accurate time keeping for navigation, their physical design and construction led Harrison down the wrong development path for almost three decades. Harrison spent seventeen years alone trying, and failing, to get H3 to work.

It was the development of a certain type of steel by another man which allowed Harrison to build the prize winning H4. Despite having an "H" label and sharing the bimetallic strip and roller bearings of H1 through 3, that pocket chronometer was a wholly different device.

Capturing H2 doesn't help Spain at all because, even if Spain can instantly divine the production methods involved, H2 is a dead end.
 
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It's worth mentioning as well that Harrison's designs were a VERY careful balance of materials and spring tensions such that natural material expansion-contraction from temperature and element changes would counteract one another, leading to a near net-zero distortion of the inner workings, hense mitigating the environmentally-induced accuracy losses. It's not just knowing how to build the devise, but what materials to use, how to install them, etc. to achieve that careful balance--i.e. things that aren't visibly apparent when reverse-engineering a finished chronometer, particularly back then.

I'm afraid even if they had the H4 the Spaniards would have a very long way to go to duplicate it. And even knowing Longitude won't do much to help the systemic organizational problems with the Spanish fleet. Non-starter, to be blunt.

I'll reiterate what Don said: check out Longitude - it's a short, very straight forward book on the invention of the Chronometer.
 
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