Anyone have details on Plymouth Hoe sea wall trig (7586)?

[stripybadger]

Visited http://trigpointing.uk/trig/7586 today, but no flush bracket and couldn't see any evidence of a bolt, it's literally just the spider. So I'm wondering if anyone knows how this was actually used? Almost looks like it was relocated here? I couldn't find it on the OS passive stations search either.

Thanks.

[agentmancuso]

I presume the theodolite was mounted on the spider in exactly the same way as on a standard pillar. No sign that it should be in the Passive Stations Database either, unless you have further details?

[ted]

Hi Bernie,

I presume the theodolite was mounted on the spider in exactly the same way as on a standard pillar.

I was wondering if the plug was removable to reveal a centre pipe. The apparant lack of sighting holes
in the wall suggests not (and positioning a centre mark without demolishing the wall would have been
tricky )


Ted

[agentmancuso]

Hm, hadn't thought of that

I guess I assumed the process of verifying the levelness of the trig pillar itself was separate from the actual triangulation.