The BBC today had story about John Harrison, who made the first really accurate watch. Parliament had offered £20,000 prize to developer of first really accurate timekeeper suitable for use at sea. At that time, there was no adequate means of determining
longitude at sea, and as a result
Admiral Sir Cloudsley Shovel and 2.000 men were drowned in a shipwreck in the Scilly Isles.http://www.allanstime.com/Publications/DWA/IONGPS95/
Here you go Dr. Bill...from AWAD Mail #71:
Dictionaries are like watches: the worst is better than none, and the best
cannot be expected to go quite true. -Samuel Johnson, lexicographer
(1709-1784)
Dear WO'N: but the most current OED could not have saved Admiral Sir Cloudsley Shovel (love that name) from losing four ships and two thousand men.
Isn't one the uninhabited rocks of the scilly island called the "the Devil" (it is 90% submurged at high tide)?
and it gave rise to being "between the devil and the deep blue sea" since Admiral Sir Cloudsley Shovel is just one of the more notable people/fleets to have bump into the scilly islands unexectedly, and with a none to favorable outcome.
does any one know for sure?
Dear of troy: I found a site with a lot about the phrase, but no mention of the Scillies:
http://phrases.shu.ac.uk/bulletin_board/7/messages/262.html
That's the one I'd heard, Dr. Bill, so it must be true.
Thanks for the site.
It's simple to figure latitude (the fist of an outstretched arm subtends about 10 degrees of arc), but longitude requires time (unless one is using a GPS). If the earth were not tilted on it's axis of rotation (with respect to the revolution about the sun), days would be of the same length, and longitude would also be simple to measure. Probably most people know this.
David Landes in [u] The Wealth and Poverty of Nations [/u] discusses the origins of attitudes towards time and the consequences those attitudes had on technological and economic development. History usually isn't something I find interesting, but I quite like this book (which I'm currently reading). I like it when someone draws sufficient dots that, after I connect them, I can discern some pattern other than a collection of randomly connected dots. (Some people can look at television snow and see messages from aliens or instructions from God.) The book is not "about" time, but time is a theme that is woven into the context of world economic history.
There should be more detail on the specific relationship between time and longitude in a book called "Longitude" by Dava Sobel." It's on my list, but I haven't gotten to it yet. The reviews I've read say it's pretty good and also short (less than 200 pages).
k
Wow, FF, I am really glad you're here!
F-Fiend, I confess ignorance. How could one easily measure longitude (if the axis of rotation were not tilted), without benefit of an acccurate chronometer as used in the current (pre-GPS) method?
Thanks -- feel free to PM if this isn't of general interest.
FF - I was going to post to mention Dava Sobel's Longitude - you beat me to it! Move it to the top of your list - it's a wonderful read. Has one of my favourite last lines ever - such a marvellous tribute to John Harrison. I'm soooo tempted to quote it here, but must resist - it wouldn't ruin the book to reveal it, it's just that it's worth waiting for.
Dear Fallible Fiend: Like Keiva, I doubt that polar tilt and the length of daylight is important for determining longitude.Sightings are done ideally at noon, and the time from noon to noon is twentyfour hours, regardless of latitude. Naturally, charts would be necessary, and distances found by spherical trigonometry.
At least that is what I believe. I promise to be cheerful if you prove me wrong.
As you well know, you and Keiva are correct. Thank you both for setting it straight. I didn't think it through. I was thinking (well, sort of) if one were at a known, fixed location in a non-tilted earth, one could use the constellations to tell the time. Even if this is true, the inference I drew would still be wrong.
Thanks,
k
Dear FF: I yield to no man in the boundlessness of my fallibility.
How could I not? Think I'll get a copy this weekend.
k