Duplicated trig(s)

General discussion about trigpoints, the TrigpointingUK website etc

Duplicated trig(s)

Postby peregrinus » Wed Jul 16, 2014 1:46 pm

I noticed that Masson Hill is down as a Pillar with condition = Converted http://trigpointing.uk/trig/4688
and also separately as a Surface Block http://trigpointing.uk/trig/8542

Perhaps there should be just the one trig here; meanwhile a few folk may be wickedly counting this one twice ;-)

I suspect there are other instances.

PS is there no hyperlink building tool on here?
peregrinus
 
Posts: 82
Joined: Tue Jun 03, 2014 6:33 pm

Re: Duplicated trig(s)

Postby ted » Thu Jul 17, 2014 3:57 pm

Hi Rob,


I noticed that Masson Hill is down as a Pillar with condition = Converted http://trigpointing.uk/trig/4688
and also separately as a Surface Block http://trigpointing.uk/trig/8542


I'm not sure that the condition of Converted is appropriate here. I think it would be better
for the Pillar to be logged as Destoyed. Then the Block is recorded separately with a condition of
Good. In the OS records, they are separate marks within a single OSGB36 statiion (SK 56/16). I don't
think its critical that one happens to have been adapted from the remains of another, such that they never existed
at the same time.

<pendant>OSGB36 never used Surface Block as a mark type; that name doesn't appear to have been
introduced until Passive Stations came along a while later. OSGB blocks are either 'Blocks' or
'Buried Blocks'</pedant>

Perhaps there should be just the one trig here; meanwhile a few folk may be wickedly counting this one twice ;-)


One trig station but two trig marks. Which takes us back to the thorny issue of which we should be counting.
:?

I suspect there are other instances.

Offhand, I can think of the same situation with Parson's Pulpit where
http://trigpointing.uk/trig/5320 is (I reckon) a destroyed pillar and
http://trigpointing.uk/trig/8431 is an OSGB36 block. Both are marks
within a single trig station SD 96/13


Regards
Ted
ted
 
Posts: 135
Joined: Sat Jun 07, 2014 8:39 am

Re: Duplicated trig(s)

Postby peregrinus » Fri Jul 18, 2014 12:21 am

ted wrote:Hi Rob,


I noticed that Masson Hill is down as a Pillar with condition = Converted http://trigpointing.uk/trig/4688
and also separately as a Surface Block http://trigpointing.uk/trig/8542


I'm not sure that the condition of Converted is appropriate here. I think it would be better
for the Pillar to be logged as Destoyed. Then the Block is recorded separately with a condition of
Good. In the OS records, they are separate marks within a single OSGB36 statiion (SK 56/16). I don't
think its critical that one happens to have been adapted from the remains of another, such that they never existed
at the same time.


Separate marks yes, but only in the sense of a destroyed marker replaced by another. As we wouldn't have a Destroyed flagstaff as well as its later replacement, and to avoid double counting, the Converted route seems neater to me. But given that both markers have logs, it's too late to go down that road and your proposed Destroyed for the original pillar seems the best way to proceed.

Offhand, I can think of the same situation with Parson's Pulpit where
http://trigpointing.uk/trig/5320 is (I reckon) a destroyed pillar and
http://trigpointing.uk/trig/8431 is an OSGB36 block. Both are marks
within a single trig station SD 96/13


Well spotted ted. I hadn't noticed that one's been duplicated too.

I've changed both to Destroyed and left the admin note visible
Changed from Converted to Destroyed as the SB is on as a separate trig mark and it doesn't seem reasonable to get two ticks for one piece of concrete...

Can be changed again if need be
peregrinus
 
Posts: 82
Joined: Tue Jun 03, 2014 6:33 pm

Re: Duplicated trig(s)

Postby ted » Fri Jul 18, 2014 3:54 pm

Separate marks yes, but only in the sense of a destroyed marker replaced by another. As we wouldn't have a Destroyed flagstaff as well as its later replacement,


In the case of replacing like for like I'd agree that it would not count as a 2nd entry in the T:UK records.
But in the case, of Masson Hill, where the type of mark has changed from pillar to block, that seems to
me that its a new mark that just happens to have been constructed from the remains of an old one.
But having said that I see that the coordinates for pillar and block are identical and have the
same levelling date; i.e OS simply re-used the old data for the block. So thats evidence in support of your case
that its a single mark. But then again they have different computing dates...

I'm confused! :roll:

Ted
ted
 
Posts: 135
Joined: Sat Jun 07, 2014 8:39 am


Return to TrigpointingUK Forum

Who is online

Users browsing this forum: No registered users and 3 guests