Author Topic: Amplitude my azimuth..what??  (Read 3151 times)

AvastMH

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Amplitude my azimuth..what??
« on: October 31, 2012, 07:18:09 pm »
Please could anyone let me know if the 'stuff' (sorry about the technical terms) in the middle of the page about amplitude and azimuth useful to note in events?

Janet Jaguar

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Re: Amplitude my azimuth..what??
« Reply #1 on: October 31, 2012, 07:32:59 pm »
To the best of my knowledge, amplitude and azimuth are compass corrections - critical to the ship's navigation that day, but quite useless to history thereafter.  Magnetic compasses in a steel ship always had trouble getting directions completely right.

I recommend to you the OWpedia thread - use your browser's search function for any questionable word.  Randi has accumulated quotes from all our sailor-members who were educating all of us landlubbers. :)

Thursday Next

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Re: Amplitude my azimuth..what??
« Reply #2 on: November 07, 2012, 06:00:53 pm »
Hmmm - I was at a planetarium show on Saturday and the term "azimuth" came up, together with "alt".  We were told that all we needed to know was that "alt" was up and "azimuth" was round.  Azimuth is such a lovely word, if only there was more opportunity to use it in conversation!

Janet Jaguar

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Re: Amplitude my azimuth..what??
« Reply #3 on: November 07, 2012, 06:28:41 pm »
You could try, next time someone on the street asks which way to walk to get to such-and-such a place. :)

I like seeing these pictures rather than trying to create a picture of word definitions.
http://www.bing.com/images/search?q=Azimuth&qpvt=Azimuth&FORM=IGRE

AvastMH

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Re: Amplitude my azimuth..what??
« Reply #4 on: November 07, 2012, 07:13:39 pm »
It'd be a corker in Scrabble if you could snatch a triple letter on 'Z', or the triple word score.

Janet Jaguar

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Re: Amplitude my azimuth..what??
« Reply #5 on: November 07, 2012, 07:53:25 pm »
I know - every time my dad pulled that off, we all got beat.  :)

AvastMH

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Re: Amplitude my azimuth..what??
« Reply #6 on: November 07, 2012, 11:07:38 pm »
I know - every time my dad pulled that off, we all got beat.  :)

 ;D ;D

Craig

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Re: Amplitude my azimuth..what??
« Reply #7 on: November 08, 2012, 01:00:27 pm »
You would have more luck using in in a French conversation. "Tous azimuths" is literally "in every direction" or "everywhere". Une guerre tous azimuths is all-out war. The dictionary says it can also mean "frenetically".

Another good reason to learn French  ;D

Kevin

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Re: Amplitude my azimuth..what??
« Reply #8 on: November 08, 2012, 03:20:15 pm »
Azimuth and amplitude can refer to two different methods of determining compass error, basically using bearings to the sun (most commonly) or other body. It is still in routine use today for determining gyro (compass) error at sea - where there are no natural ranges to 'swing' the compass on. I've used these techniques to reconstruct the compass card after the ship was struck by lighting. The strike - aside from blowing the HF radio antennas completely off the mainmast - completely magnetized the ship resulting in transient compass error of up to +/- 25 degrees. See also the chapter in Mody Dick about 'thunderstruck' - which was incidentally lifted from Scoresby's Account of the Arctic Regions.

AvastMH

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Re: Amplitude my azimuth..what??
« Reply #9 on: November 08, 2012, 06:04:55 pm »
that's fascinating - thanks Kevin.   The lightning sounds really a bit too exciting!