Northwich Berntsen

[ProSpec]

I have walked past this Berntsen many times over the years without knowing what it was but since joining this site and finding out what it is I haven't got round to logging it until now. However on looking at the database this doesn't appear to exist, I do not believe it is very old (10-15 years) and probably installed for the underpinning of Northwich (there are widespread salt mines all under this area and Northwich suffers from subsidence).
Perhaps someone could check this and add to the database.

Location: SJ 65892 741106

I would add photo's if I knew how.

I would ask on Trigonomy but have never managed to join, my requests are either not received or ignored?

Cheers, Steve Rennie

[ted]

Hi Steve,

Northwich Berntsen

I have walked past this Berntsen many times over the years without knowing what it was but since joining this site and finding out what it is I haven't got round to logging it until now. However on looking at the database this doesn't appear to exist, I do not believe it is very old (10-15 years) and probably installed for the underpinning of Northwich (there are widespread salt mines all under this area and Northwich suffers from subsidence).
Perhaps someone could check this and add to the database.

Location: SJ 65892 741106

As far as I know, the OS only used these markers for passive stations, sometimes as
a replacement for a bolt (for example, at South Cave, http://trigpointing.uk/trig/601)

But the nearest passive station to your grid ref is 10km away (Cranage). Are you sure its a Berntsen and
not perhaps something like a Fenomark, where non-OS examples are known to exist? Berntsens
have the inscription 'Survey Monument Do Not Disturb' on the metal lid with sometimes
extra lettering 'Ordnance Survey Benchmark' on the outer edge. See for example
http://trigpointinguk-photos.s3.amazona ... P42944.jpg

Berntsen is an international organisation; they have a web site http://www.berntsen.com
where you can buy your very own survey marker (starting at $56.93 with a discount for bulk purchase )


Regards
Ted

[ProSpec]

Looks like a Bernsten to me?

Its in the middle of a pavement so gets walked on a lot.

Regards, Steve

[agentmancuso]

Yes, it is. But Berntsen is a commercial company, so produce equipment for many private surveyors. So although a survey point of some sort, it has nothing to do with the OS, just like the numerous rivet/washer points placed by private companies all over the country.

[ted]

Hi Steve,

Thanks for the photo. Interesting that the Berntsen is set in tarmac. AFAIK, OS always placed
theirs in roadside verges. I think that, in the absence of evidence that this Berntsen was installed
by the OS, we have to conclude that it isn't one of theirs.

We perhaps could do with a wiki page for non-OS survey markers. This might include your Berntsen
along with EABM, NRA, non-OS Fenomarks, 'Post Office' benchmarks and other miscellaneous
marks frequently seen in pavements etc.


Regards
Ted

[ProSpec]

Thanks Ted,

I did not realize that other organisations installed Bernstens, etc.
It was probably installed when the salt mines under Northwich were being stabilised 10 years ago (to allow accurate measurements of any subsidence in the town centre?)

I think the extra section to the wiki would be a great idea and perhaps a separate database for the more substantial extra points (I have seen lots of the pavement type markers (yellow discs, etc and I would not expect those to be catalogued)

Regards, Steve

[spargazer]

The EA would never ever place a marker in tarmac but there could be solid concrete below. There is an outfit called "Cheshire Brine Subsidence Compensation Board" that used to carry out surveys, not sure now what they do. Lieca Smartnet is used a lot now.

[peregrinus]

I think the extra section to the wiki would be a great idea and perhaps a separate database for the more substantial extra points (I have seen lots of the pavement type markers (yellow discs, etc and I would not expect those to be catalogued)

Another possibility is to set up a Facebook group for non OS survey markers: easy to post photos there. Unless someone volunteers to set up a more formal database.

We could add a few Hydro board trigs...

[spargazer]

Network rail have a lot of reflector targets glued to platforms and walls, they are everywhere.

[Cootking]

I just found a Bernstein at Cogra Moss in the western Lake District. Moping along on a dismal, cloudy day and there it was. No outer lettering so not OS but a good find which brightened up my day.