Another Virginia Mystery

[+bicknell]

There's a series of missing marks that are interesting to me. I get the feeling they have been removed on purpose, but have no direct evidence.

 

The marks in question are:

 

HV9152

HV9153

HV9154

 

Note these were all set at the same approximate time by the same company. I've found a number of other MSI marks before, they generally do really good work. Note also all of these are "BERNSTEN MODEL W-1-B BREAK-OFF HIGHWAY MONUMENT", which I've never seen before. Descriptions are good for 9152 and 9154 so I'm sure we were in the right spot, 9153 is a little unsure.

 

Later the same day we found this mark:

 

HV8202

 

It's a bit southwest. It was set in 1986. Again, good description, good objects to measure from, but no mark at that location.

 

I almost wonder if there were a bunch of marks determined to be "wrong", and they were pulled up.

[Bill93]

For HV9152 I can't make sense of the NW direction

NORTHWEST OF THE SOUTHEASTERN CORNERPOST OF THE CEMETARY WALL

because that would put it inside the wall whereas everything else indicates outside. Or am I mixed up?

 

But that is pretty much moot if you had other measurements that agreed with the GPS on an adjusted horizontal location.

[holograph]

See Bernsten Break-off Monuments.

 

It could be that their life along a highway just makes them susceptible to damage from accidents, plows, brush clearing, etc.

 

It looks like they are designed so that a magnetic fragment remains in place underground so that they can be located in case the upper portion goes missing. Maybe some of the pros have had experience with them.

[+donbadabon]

I know nothing about benchmarks, so please excuse me if this is a dumb statement.

On those benchmark pages, they have the note:

1/29/1992 by MSI (GOOD)

RECOVERY NOTE BY MEASUREMENT SCIENCE INCORPORATED 1992 RECOVERED IN GOOD CONDITION.

Being a layperson, this sounds to me like it was removed (recovered) in 1992.

[holograph]

"Recovered" is just the surveying term for finding the station, it doesn't mean that the mark was removed. The note means that Measurement Science Inc. found the mark in good condition in 1992 (and left it there). If they had removed it, they would have noted that they destroyed the mark.

[+donbadabon]

Ahh, I see. Thanks!

[+Black Dog Trackers]

You'll find that you have to get used to understanding 'survey speak' when reading to-reach instructions and recovery notes.

[TerraVador]

 HV8202'THE STATION IS A WI-B BERNTSEN ALUMINUM DISK SET FLUSH WITH THE GROUND
HV8202'AND IS STAMPED---14 LITTLE BULL RUN 1986---. THE STATION IS 12.45
HV8202'FEET NORTHWEST OF THE WOODEN END POST OF WOODEN FENCE, 24.62 FEET EAST
HV8202'OF A SHINER IN THE CENTER OF ROUTE 705, 46.34 FEET SOUTH OF POWER POLE
HV8202'31.

 

Can someone please tell me what a "SHINER" is?

[+Black Dog Trackers]

I suspect it's one of those things called a cat eye that reflects back headlights at night. It reminds me of a picture of a funny highway sign I saw long ago. The sign said "CAT EYES REMOVED 1000 FEET".

 

I guess it could also be some temporary surveyors mark pounded into the asphalt, but I bet it's a cat eye.

[+jwahl]

A shiner is nothing but a shiny disk, much like a tin can lid attached to a pole or in the ground with a nail in the center. These are often used as surveying references in poles and sometime in asphalt.

 

A breakoff monument is designed to have the top part break off if struck with earth moving equipment, leaving behind a less disturbed subsurface part. Usually bernsten monuments had magnets in them. We should check the catalog and see if that model might still exist to get an idea. Most of the monument is probably aluminum and so that might affect some kinds of metal detectors. Surveying metal detectors work on magnetic fields and so need the magnet or a ferrous monumnet material.

 

Note that some of the NGS data sheets say there is a bar magnet.

 

Here are some modern models:

 

http://www.berntsen.com/products.aspx?c=41

 

I am pretty sure the model described W-1-B is a different design.

 

- jlw

[evenfall]

Here is a photo of the shiners we commonly use, when we use them

 

http://www.evanschristmas.com/evanss/produ...tail.asp?ID=152

 

There are many brands, we are apt to use what there is available.

 

I like to nail them down with a concrete nail, or a Mag Nail, which is also magnetized so it can be more easily found.

 

Rob

Edited September 19, 2005 by evenfall