You mean you need to know you are looking for sixpence before you find what you are looking for? How odd, when it would be much better to find it when you don't know what you are looking for?
I think you mean that it is not like an associative memory - you would like to think, 'plus signs with....' and it would point you directly there? Actually, it almost does do that if you look at the book.
The associative bit is that the thing you are looking for is in the water and probably a hazard so you look on that page - UREKA !!
Or did you mean you don't go looking for it before you find it - at sea !! Nasty thought.
Something like that. You have to know enough to know that it is some form of Rock/Obstruction as opposed to a type of nav aid or buoy, or something to do with tides and currents, before you find it.
If you don't know that much, then trying to find it by starting at page one and working through would be a very tedious business.
I've got a symbol that took me ages to work out (It's logical but obscure). It's a compass needle in a circle. Now knowing what it means, I suppose that it's only necessary as long as you know what it means - But why do Imray need to show it on their charts as it has no relevence to yotties?
5011 p58. Pilot boarding place. Do I win a prize? It's shown on the Admiralty chart by the fairway for my home port of Fleetwood. As I've seen a pilot boat waiting there my guess was also correct.
BUT, if you take an Admiralty chart of Anglesey, it shows the pilot pick up point about 1 mile north west of Trwyn Du whereas the pilots out of Amlwch pick up about 2 miles east of Lynas - A difference of about 4 miles - Most stange.
Always thought the one of Tryn Du is for the Menai Strait (never seen one for the gravel ships going to Penrhyn) and as useful as the one off Caernafon Bar since the oil terminal at c'fon was closed...