Time and Navigation
204
post-template-default,single,single-post,postid-204,single-format-standard,ajax_fade,page_not_loaded,,select-theme-ver-4.1,menu-animation-underline,wpb-js-composer js-comp-ver-5.2,vc_responsive

Time and Navigation

Time and Navigation

I had the privilege recently to visit the Royal Observatory in Greenwich, England and see firsthand not only the demarcation of 0° longitude, known as the Prime Meridian or the Greenwich Meridian, but also John Harrison’ s revolutionary timepieces.  This visit is a rite of passage for mariners everywhere.

For the uninitiated to celestial navigation or maritime, this location and these timepieces are essential aspects of maritime history and, in turn, the history of the world.  It was not so long ago, as recently as the early parts of the 17th century that time could not be kept at sea.  Chronometer technology today is ubiquitous but it was not always that way.

The problem of keeping time was paramount because it is a necessary piece of celestial navigation calculations, allowing mariners to determine their position at sea.  Without it, sailors could not know for sure where in the ocean they were.  As a result, many ships were lost and investment in ocean voyages was limited because their outcomes were unpredictable.  World trade could not grow.

It is easy to determine latitude by using the sun but knowing longitude is dependent on knowing hours and minutes.  For every 15° that one travels eastward, the local time moves one hour ahead.  Similarly, travelling West, the local time moves back one hour for every 15° of longitude.  Therefore, if we know the local times on two points on Earth, we can use the difference between them to calculate how far apart those places are in longitude.

Sailors in the 17th century could determine the local time of their location by observing the sun but they also needed to know the time at a reference point, such as Greenwich, in order to calculate their longitude.  This required an accurate timepiece that could be carried aboard ship.  Although clocks existed in that day, building one that remained immune to the motions and effects of the sea and kept accurate time was an elusive challenge.

Enter John Harrison.  Harrison was a carpenter by trade and began building longcase clocks from wood with wooden mechanisms.  Over time his clock designs moved through numerous evolutions as he improved each subsequent design.  The challenges he overcame included building mechanical pieces immune to gravity, moisture, or temperature change.  His designs truly were original and revolutionized sea-going time keeping.  As a result of his work Harrison won the longitude prize, issued by the Board of Longitude, a body formed to promote finding a solution to the problem.  The secondary result was that navigation and world trade were changed forever.

A photo of Harrison’s H1, the first version of his marine chronometer, can be seen above.  The H4, which could be produced on a mass scale, is below.  There is much more to the story, which you can find in Dava Sobel’s best-selling work, Longitude: The True Story of a Lone Genius Who Solved the Greatest Scientific Problem of His Time.  I recommend it to anyone with a penchant for history, the sea, or the inner workings of clocks.

Tags:
15 Comments
  • gamefly free trial

    May 2, 2019 at 11:50 am

    We are a group of volunteers and starting a new scheme in our community.
    Your site offered us with valuable information to work on. You have done a
    formidable job and our entire community will be
    thankful to you.

  • gamefly free trial

    May 4, 2019 at 12:34 pm

    This is a very good tip especially to those new to
    the blogosphere. Simple but very accurate info… Thanks for sharing this
    one. A must read post!

  • gamefly

    May 4, 2019 at 6:06 pm

    Hello There. I found your blog the usage of msn. This is an extremely smartly written article.
    I’ll be sure to bookmark it and come back to learn extra of your helpful
    info. Thank you for the post. I’ll certainly return.

  • minecraft download pc

    May 8, 2019 at 7:10 pm

    Do you mind if I quote a couple of your articles as long as
    I provide credit and sources back to your website? My website is
    in the exact same niche as yours and my users would truly benefit from a lot
    of the information you provide here. Please
    let me know if this alright with you. Regards!

  • how to download minecraft free

    May 9, 2019 at 3:04 am

    I like the valuable info you provide in your articles. I’ll bookmark your weblog and check again here regularly.
    I am quite sure I’ll learn many new stuff right here!
    Good luck for the next!

  • g

    May 11, 2019 at 4:28 pm

    I am curious to find out what blog system you’re utilizing?
    I’m experiencing some small security issues with my latest blog and I would
    like to find something more safeguarded. Do you have any suggestions?

  • mojang minecraft download

    May 12, 2019 at 6:18 am

    I feel this is one of the so much vital information for me.

    And i am glad reading your article. However should statement on few common issues,
    The web site style is ideal, the articles is in reality nice : D.
    Just right activity, cheers

  • g

    May 13, 2019 at 7:25 pm

    This information is invaluable. How can I find out more?

  • minecraft free download pc

    May 14, 2019 at 1:30 am

    You’re so cool! I do not believe I’ve truly read through something like
    this before. So wonderful to discover somebody with a few genuine thoughts on this
    topic. Really.. many thanks for starting this up. This website is something that
    is needed on the web, someone with a bit of originality!

  • download minecraft for free

    May 15, 2019 at 7:27 am

    I have to thank you for the efforts you’ve put in writing this blog.
    I’m hoping to see the same high-grade content by you later
    on as well. In truth, your creative writing abilities has inspired
    me to get my own, personal blog now ;)

  • Randmig

    June 10, 2019 at 4:47 am

    Overnight Propranolol Cialis Generika Gunstig Kaufen cialis canada Cialis 10 Mg Erfahrung

  • Randmig

    June 22, 2019 at 3:02 pm

    Ciprofloxacine Teva 500 Mg viagra prescription Discount Cialis 24 Hour Shipment Discount Fedex Shipping Macrobid Furadantin Website Low Price

  • Randmig

    July 5, 2019 at 1:22 pm

    Levitra Sans Ordonnance Pharmacie cialis 5 mg best price usa Can Women Take Kamagra Viagra Ohne Rezept Kaufen Berlin Diclofenac Online Pharmacy Us No Rx

  • Randmig

    July 16, 2019 at 12:32 am

    Generic Isotretinoin buy generic cialis Generic Tab Bentyl Purchase Internet Online Free Doctor Consultation

  • Randmig

    July 25, 2019 at 3:06 am

    Beipackzettel Viagra Online levitra without rx in the united states Review Canadian Pharmacy Viagra Keflex For Staph

Post a Comment