Imray chart c65...what does this mean?

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Matata

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Just looking at this chart and there is a rock approx 10 miles west of Colonsay. It reads LT HO Dubh Artach (14) Fl(2)30s44m20M. what does the (14) refer to? Fastest fingers first and a happy,safe and enjoyable New year to you and yours. Nik
 
Just had a look at South Stack Lighthouse, Anglesey on a "visit my harbour" chart. No mention of the height of the rock it is built on, although it can be deduced. i wonder why some have the number in brackets before the light characteristics, and some dont?
 
You will find that if a rock or small island etc is too small for a spot height to be placed on it, its height is shown as close as practicable and in brackets, so that it is not taken as a sounding etc. If Dubh Artach didn't have a lighthouse, it would still be shown as (14).
 
GHA said:
Interesting. Looks like the 14m 'just happens' to be part of the name, not part of the IMO(& admiralty) symbols and abbreviations? Or part of depths I-11?
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Heights of freestanding rocks in brackets are of course a perfectly standard notation, unrelated to any lights they might or might not have on top. I can’t see the chart in question, but is the spot height perhaps just placed next to the “Lt Ho” and light character, and not intended to be part of either of them?

Pete
 
Why would one want the height of the rock on which the light stands when there is already a system for indicating drying heights, independent of light characteristics.
 
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Those of you who find this confusing might be better using the BA Chart. It just says "Dubh Artach (14m)", and then goes on to give the characteristics of the lighthouse.
 
The VMH admiralty charts show this as being on two separate lines :

Dubh Artach (14)
Fl(2)30s44m20M

The OpenCPN Vector charts appear a little lacking here, all that's shown is "Dubh Artach" and the LtHo symbol.
 
Me culpe - still plastered yesterday. If it was a unlighted beacon it would be the height of the beacon. If lighted the small m is the height of light and the brackets is the height of the rock. The VMH has the right wording. I'm better now!
 
Twisterowner said:
Why would one want the height of the rock on which the light stands when there is already a system for indicating drying heights, independent of light characteristics.
Click to expand...

And the system for indicating heights, when there isn’t space to draw the height in its exact location, is to put it nearby with brackets around it. Which is what they have done.

It does seem a little superfluous to include the height when the thing has a dirty great lighthouse on top of it - you’re not going to struggle to identify it which is the normal reason for showing heights. But it’s not wrong.

Pete
 
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prv said:
And the system for indicating heights, when there isn’t space to draw the height in its exact location, is to put it nearby with brackets around it. Which is what they have done.

It does seem a little superfluous to include the height when the thing has a dirty great lighthouse on top of it - you’re not going to struggle to identify it which is the normal reason for showing heights. But it’s not wrong.

Pete
Click to expand...

Thnk you for explaining it
 
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