Determining Longitude with a Clock - Watch and Learn #58

In today's Watch and Learn, I’ll discuss why the marine chronometer was just an important invention. With it, mariners could determine their longitude, making navigation much more precise.

For more in-depth knowledge of this truly unique topic, check out the literary work of Dava Sobel. I recommend reading the book called Longitude: The True Story of a Lone Genius Who Solved the Greatest Scientific Problem of His Time and Winner of British Book of The Year.

Thank you for watching.

[billcosgrave]

Love it! I actually own two old Hamilton marine chronometers from WW2. One of them, Hamilton model 22 with a Swiss lever escapement, keeps +/- 2 seconds a day and it is 75 years old and never been regulated. Although I did have to replace the main spring recently and to my complete surprise, parts are still available for these old instruments. The other one, Hamilton model 21, is a detent escapement with a chain and fusee. It was an observatory instrument but fell into disuse. It still functions well enough but needs to be serviced to bring it back into chronometer spec. The Dava Sobel book is one of my favorites, a great read.

[WalterDavidRiffmon]

I’m always amazed at how ingenious people where without technology. In some ways they possessed superior knowledge because they understood principles rather than relying on modern conveniences. Thanks so much for this video Marc.

[RogerMillerInVA]

I think this was your best video ever, Marc. Thank you.

[jefferyneu]

I can’t even imagine being smart enough to figure out that method with nobody teaching it to me. The person who figured it on his own was beyond brilliant! Thank you Marc. I really look forward to all of your content!

[triplesgood]

Great video. I love the watch and learn spots. Thanks Marc.

[jamesdunn]

Thank you for such a straightforward explanation.

[NagoyaT]

Thank you for taking the mystery out of longitude! Great job presenting a complex subject in understandable terms!

[JBFire]

John Harrison’s marine chronometers can be seen at Greenwich observatory, London. Outstanding timepieces. Thank you for the great video.

[ajones]

Nice watch and learn episode!!! Thanks for taking the time to explain this!!!

[android]

Hey Mark, just wanted to thank you again for taking your time to make these educational videos. Looking forward to the next one.

[StefaanVdV]

Nice and informative video, thanks for sharing Sir 👍

[generalmortars]

That is actually GENIUS.
I knew it had something to do with clocks but I never sat down to think it through until just now.

[drhall]

Great! Perfect simplified explanation! Thanks Mark!

[LA_Viking]

A pretty workmanlike presentation. The guys on the boat would be impressed.

[doctorhamburger]

This finally made it click for me. And it was entertaining. Thank you!

[Mike_Costello]

I read that book in 1999 and I knew as soon as I saw the title of this video you were going to bring it up. In a way its an awesome book.
Thanks for this video! For others here, the clock was made of wood and the natural oils in there lubricated it well enough for it to remain accurate. Plus the wood ( I can't recall which type) resisted expansion and contraction with temp and the oils helped it remain consistent in moisture content.

[ronblack]

Love the educational videos from time to time. So to speak. Be well!

[benmoeller]

Very interesting. I had often wondered why the chrono was so critical. Thanks Mark.

[profesordubiel]

I was wandering for years how it work. And now i know! Thanks

[RobbieCaptMilkboneBaxter]

Love it, Great simple lesson of a lost art. Kids need to learn the old ways so not to take for granted what we have... YAR!