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PostPosted: Tue May 29, 2018 10:53 am
by SJW1960
My copy of the South Pennines OL 21 map (2002 edition) clearly shows a trig-pillar at grid SD984429 (adjacent 'Wainman's Pinnacle'). However, during a brief visit, I was unable to find it 'on the ground' and no-one here seems to have logged it previously. Is this a cartographic error or am I missing something?

Re: SD984429

PostPosted: Tue May 29, 2018 12:50 pm
by ted

Wainmans Pinnacle *is* the trig station;
- its recorded in TPUK as an Intersected Station; a few more details on these pages:

So in this instance, the triangulation symbol on your map does not indicate that there
was ever a pillar at this location. It dates from a time when the OS would mark other
kinds of trig station with this symbol. But its unclear why it wasn't removed from later
editions of the map; maybe an oversight. Stoodley Pike is another example in the same area.


Re: SD984429

PostPosted: Wed May 30, 2018 11:55 am
by SJW1960
Thanks Ted.

Re: SD984429

PostPosted: Thu May 31, 2018 6:51 pm
by agentmancuso
... maybe an oversight...

Yes, undoubtedly an oversight. For a while pillar stations were marked in cyan but non-pillar stations like the one above were marked in black. When the OS decided to remove non-pillar stations, the process seems to have been manual, as quite a few were missed. Later, all remaining stations, pillar or otherwise, were printed in cyan, obscuring the difference.