When Compasses Misbehave

[blessmycottonsocks]

As a spin-off from the Tríbeč mountains thread, in which I mentioned compasses behaving anomalously, I referred to my own similar experience.

I already owned an antique brass compass, which is beautiful, but not the most practical device for hiking. I therefore treated myself to a modern military-style prismatic compass shortly after the first Covid lockdown.

My motives were quite simply the pleasure in using traditional navigation tools, rather than relying on Google maps, Strava or whatever.

I'd already used it for a few short hikes and had become comfortable with taking readings and map navigation.

After the 2nd lockdown I decided to hike the Devil's Punchbowl trail in Hindhead Surrey. It's only around 3 or 4 miles, but I extended it by doing part of the adjacent Gibbet Hill hike first. So, I took my first bearing from the National Trust carpark and set off.

On the second half of my hike, I was just past the lowest point of the punchbowl depression maybe a mile or so west of the carpark and stopped for a gulp of water and to check directions back towards the carpark. It was not strictly necessary, as the trails are fairly well marked, but I did it for my own satisfaction. I knew that the carpark should be due east of my current position and the compass duly showed north as being to my left. With the compass still open, I kept watching it as I continued walking straight along the trail eastwards.
Strangely, the compass' needle strayed away from north and flicked around towards east. I backtracked several paces and the reverse happened.
When I repeated my steps and checked my reading using Google Maps though, nothing unusual occurred.

A quick Google reveals that the geology of the Devil's Punchbowl is primarily sandstone and clay. I haven't found any mention of substantial iron deposits and am a bit baffled as to the cause of this compass glitch.

Any ideas?

 

[Floyd]

As a spin-off from the Tríbeč mountains thread, in which I mentioned compasses behaving anomalously, I referred to my own similar experience.

I already owned an antique brass compass, which is beautiful, but not the most practical device for hiking. I therefore treated myself to a modern military-style prismatic compass shortly after the first Covid lockdown.

My motives were quite simply the pleasure in using traditional navigation tools, rather than relying on Google maps, Strava or whatever.

I'd already used it for a few short hikes and had become comfortable with taking readings and map navigation.

After the 2nd lockdown I decided to hike the Devil's Punchbowl trail in Hindhead Surrey. It's only around 3 or 4 miles, but I extended it by doing part of the adjacent Gibbet Hill hike first. So, I took my first bearing from the National Trust carpark and set off.

On the second half of my hike, I was just past the lowest point of the punchbowl depression maybe a mile or so west of the carpark and stopped for a gulp of water and to check directions back towards the carpark. It was not strictly necessary, as the trails are fairly well marked, but I did it for my own satisfaction. I knew that the carpark should be due east of my current position and the compass duly showed north as being to my left. With the compass still open, I kept watching it as I continued walking straight along the trail eastwards.
Strangely, the compass' needle strayed away from north and flicked around towards east. I backtracked several paces and the reverse happened.
When I repeated my steps and checked my reading using Google Maps though, nothing unusual occurred.

A quick Google reveals that the geology of the Devil's Punchbowl is primarily sandstone and clay. I haven't found any mention of substantial iron deposits and am a bit baffled as to the cause of this compass glitch.

Any ideas?

It was too close to something metal about your person perhaps?

 

[maximus otter]

As a spin-off from the Tríbeč mountains thread, in which I mentioned compasses behaving anomalously, I referred to my own similar experience.

I already owned an antique brass compass, which is beautiful, but not the most practical device for hiking. I therefore treated myself to a modern military-style prismatic compass shortly after the first Covid lockdown.

My motives were quite simply the pleasure in using traditional navigation tools, rather than relying on Google maps, Strava or whatever.

I'd already used it for a few short hikes and had become comfortable with taking readings and map navigation.

After the 2nd lockdown I decided to hike the Devil's Punchbowl trail in Hindhead Surrey. It's only around 3 or 4 miles, but I extended it by doing part of the adjacent Gibbet Hill hike first. So, I took my first bearing from the National Trust carpark and set off.

On the second half of my hike, I was just past the lowest point of the punchbowl depression maybe a mile or so west of the carpark and stopped for a gulp of water and to check directions back towards the carpark. It was not strictly necessary, as the trails are fairly well marked, but I did it for my own satisfaction. I knew that the carpark should be due east of my current position and the compass duly showed north as being to my left. With the compass still open, I kept watching it as I continued walking straight along the trail eastwards.
Strangely, the compass' needle strayed away from north and flicked around towards east. I backtracked several paces and the reverse happened.
When I repeated my steps and checked my reading using Google Maps though, nothing unusual occurred.

A quick Google reveals that the geology of the Devil's Punchbowl is primarily sandstone and clay. I haven't found any mention of substantial iron deposits and am a bit baffled as to the cause of this compass glitch.

Any ideas?

I have no idea of the geography or history of that area, but a large lump of buried iron wouldn't be unique in Surrey:

"An extremely rare Second World War tank has been dug up at Denbies by WW2 enthusiast Rick Wedlock.

Rick approached Denbies last year regarding the excavation. Following an exploratory dig in January which revealed the top part of the tank, the full excavation took place on Tuesday 23rd May. The English “Covenanter” tank was dug up from beneath the vineyard as part of a new series commissioned by the History Channel and is one of two tanks buried at the site by the Canadians, who were training on the estate, at the end of the war.

Denbies Wine Estate Ltd
London Road
Dorking, Surrey
RH5 6AA"

https://www.denbies.co.uk/extremely-rare-second-world-war-tank-has-been-dug-up-at-denbies/

maximus otter

 

[blessmycottonsocks]

It was too close to something metal about your person perhaps?

I did have car and house keys in my pocket, but why would they affect the compass only for that 100 yards or so of the trail?

There was no sign of any metal fence or similar nearby. Cannot vouch for the area being bereft of buried tanks though!

 

[SimonBurchell]

As a spin-off from the Tríbeč mountains thread, in which I mentioned compasses behaving anomalously, I referred to my own similar experience.

I already owned an antique brass compass, which is beautiful, but not the most practical device for hiking. I therefore treated myself to a modern military-style prismatic compass shortly after the first Covid lockdown.

My motives were quite simply the pleasure in using traditional navigation tools, rather than relying on Google maps, Strava or whatever.

I'd already used it for a few short hikes and had become comfortable with taking readings and map navigation.

After the 2nd lockdown I decided to hike the Devil's Punchbowl trail in Hindhead Surrey. It's only around 3 or 4 miles, but I extended it by doing part of the adjacent Gibbet Hill hike first. So, I took my first bearing from the National Trust carpark and set off.

On the second half of my hike, I was just past the lowest point of the punchbowl depression maybe a mile or so west of the carpark and stopped for a gulp of water and to check directions back towards the carpark. It was not strictly necessary, as the trails are fairly well marked, but I did it for my own satisfaction. I knew that the carpark should be due east of my current position and the compass duly showed north as being to my left. With the compass still open, I kept watching it as I continued walking straight along the trail eastwards.
Strangely, the compass' needle strayed away from north and flicked around towards east. I backtracked several paces and the reverse happened.
When I repeated my steps and checked my reading using Google Maps though, nothing unusual occurred.

A quick Google reveals that the geology of the Devil's Punchbowl is primarily sandstone and clay. I haven't found any mention of substantial iron deposits and am a bit baffled as to the cause of this compass glitch.

Any ideas?

A couple of points. First, which car park did you use? The main Punchbowl carpark is at the southwest edge of the Devil's Punchbowl, so you should have been east of the car park.

Secondly, the sandstone in the vicinity is ironstone, with thick veins of iron running through it. I haven't seen it on the surface around the Punchbowl, but about 3ish miles north(ish) the ironstone veins break the surface at the Devil's Jumps.

Above the Punchbowl, the line of the old A3 has a lot of metal detritus left in situ after the old road was torn up - all buried now, but a bit far from where you were.

As Max says above, it could be WWII junk. There was a lot of training going on in the local area during WWII and the Canadians were all over the shop. There are also a lot of old pieces of iron farm junk (gates and suchlike) left abandoned where they stood in the local area.

 

[blessmycottonsocks]

A couple of points. First, which car park did you use? The main Punchbowl carpark is at the southwest edge of the Devil's Punchbowl, so you should have been east the car park.

Secondly, the sandstone in the vicinity is ironstone, with thick veins of iron running through it. I haven't seen it on the surface around the Punchbowl, but about 3ish miles north(ish) the ironstone veins break the surface at the Devil's Jumps.

Above the Punchbowl, the line of the old A3 has a lot of metal detritus left in situ after the old road was torn up - all buried now, but a bit far from where you are.

As Max says above, it could be WWII junk. There was a lot of training going on in the local area during WWII and the Canadians were all over the shop. There are also a lot of old pieces of iron farm junk (gates and suchlike) left abandoned where they stood in the local area.

I was parked near the visitors' centre and café. I walked a rough figure of 8 trek, doing the eastern Gibbet Hill section first, before re-crossing the car park and doing the full perimeter loop around the Punchbowl. Due to the quirks in the trail, this meant me heading w,n,e,s before getting back to my car.

 

[SimonBurchell]

I was parked near the visitors' centre and café. I walked a rough figure of 8 trek, doing the eastern Gibbet Hill section first, before re-crossing the car park and doing the full perimeter loop around the Punchbowl. Due to the quirks in the trail, this meant me heading w,n,e,s before getting back to my car.

Nice route, especially if it's clear - if you plan it right, you get great views northeast to London, south to the South Downs and north to Camberley.

None of that should place you west of the car park, which would put you in Hindhead itself, unless you also dropped down into Golden Valley.

 

[Floyd]

For people who don't know the area (with the old route, pre-tunnel, on the left map);

 

[maximus otter]

I was parked near the visitors' centre and café. I walked a rough figure of 8 trek, doing the eastern Gibbet Hill section first, before re-crossing the car park and doing the full perimeter loop around the Punchbowl. Due to the quirks in the trail, this meant me heading w,n,e,s before getting back to my car.

maximus otter

 

[blessmycottonsocks]

...unless you also dropped down into Golden Valley.

I think you're right. I wasn't sticking to the marked routes and did stray some distance west.
It's put me in the mood to do the walk again sometime soon. If I can find the exact same spot where my compass behaved erratically, I will try to film it on my phone next time.

 

[SimonBurchell]

I think you're right. I wasn't sticking to the marked routes and did stray some distance west.
It's put me in the mood to do the walk again sometime soon. If I can find the exact same spot where my compass behaved erratically, I will try to film it on my phone next time.

1:25000 map, with Golden Valley:

 

[Floyd]

Was looking for any anomalies in the area, but the only thing I can see is an old brickworks.
Maybe some metal machinery/mining equipment left over?;

 

[blessmycottonsocks]

Incidentally, one hot summer several years earlier, I also tried dowsing, using a springy y-shaped twig, whilst crossing the Punchbowl valley bottom.
The twig was pulled down quite noticeably at one point, which probably coincided with where, in wetter weather, a small stream flows.

 

[SimonBurchell]

Was looking for any anomalies in the area, but the only thing I can see is an old brickworks.
Maybe some metal machinery/mining equipment left over?;

View attachment 73260

And that red dot is quite a way off, on the other side of a substantial ridge.

 

[SimonBurchell]

Incidentally, one hot summer seversl years earlier, I also tried dowsing, using a springy y-shaped twig, whilst crossing the Punchbowl valley bottom.
The twig was pulled down quite noticeably at one point, which probably coincided with where, in wetter weather, a small stream flows.

In the thicket down in the bottom there is a spring with a permanent stream and a tiny little waterfall.

 

[blessmycottonsocks]

Just to test the car keys hypothesis, I took a reading with and without my keys adjacent to the compass.
Even though I carry a fair chunk of metal on my key ring, including a bottle opener and a metal Cornish flag, there was no appreciable difference when the keys were moved around and right next to the compass.

 

[SimonBurchell]

Just to test the car keys hypothesis, I took a reading with and without my keys adjacent to the compass.
Even though I carry a fair chunk of metal on my key ring, including a bottle opener and a metal Cornish flag, there was no appreciable difference when the keys were moved around and right next to the compass.

View attachment 73350

You'd have thought the Cornish flag would point it westwards.

 

[charliebrown]

My wife’s first cousin was a tug boat captain retired now, but sometimes he would help crew private pleasure boats going to Bermuda.

He said once in the Bermuda Triangle their compass would just spin and the owners decided to turn back Miami.

That has to be strange.

 

[blessmycottonsocks]

My wife’s first cousin was a tug boat captain retired now, but sometimes he would help crew private pleasure boats going to Bermuda.

He said once in the Bermuda Triangle their compass would just spin and the owners decided to turn back Miami.

That has to be strange.

Exactly - and you cannot even blame iron deposits when a ship's compass (or aircraft's) misbehaves.

 

[Sharon Hill]

Exactly - and you cannot even blame iron deposits when a ship's compass (or aircraft's) misbehaves.

My wife’s first cousin was a tug boat captain retired now, but sometimes he would help crew private pleasure boats going to Bermuda.

He said once in the Bermuda Triangle their compass would just spin and the owners decided to turn back Miami.

That has to be strange.

This is a textbook FOAF story. One person's anecdote does not make for a sound generalized conclusion.

 

[blessmycottonsocks]

This is a textbook FOAF story. One person's anecdote does not make for a sound generalized conclusion.

Yes Miss.
Sorry Miss.
Won't happen again Miss.

 

[Floyd]

One person's anecdote does not make for a sound generalized conclusion.

Unless it's one of my anecdotes.................

 

[Sharon Hill]

Yes Miss.
Sorry Miss.
Won't happen again Miss.

View attachment 73486

Why was that necessary? It doesn't add to the discussion.
Lots of other (male) posters have critical or opposing comments, but they don't get called out for them. Maybe don't do this.

 

[blessmycottonsocks]

Why was that necessary? It doesn't add to the discussion.
Lots of other (male) posters have critical or opposing comments, but they don't get called out for them. Maybe don't do this.

Hi Sharon and I'm sorry if I came over as snarky.
I just felt there have been a few instances recently when you appeared to be a bit out of tune with the general vibe of the thread.
Most of us are here to enjoy some light-hearted discussion of Fortean themes, and a constant reminder not to be so silly, as there's really nothing out-of-the-ordinary going on did strike me as a tad pedagogical.
I do appreciate that's where you get your jam. Just be aware that other forumists get theirs from stepping outside of the rational to share and speculate about Forteana - and we don't need to be told that's it's mostly bunkum!

 

[Sharon Hill]

Hi Sharon and I'm sorry if I came over as snarky.
I just felt there have been a few instances recently when you appeared to be a bit out of tune with the general vibe of the thread.
Most of us are here to enjoy some light-hearted discussion of Fortean themes, and a constant reminder not to be so silly, as there's really nothing out-of-the-ordinary going on did strike me as a tad pedagogical.
I do appreciate that's where you get your jam. Just be aware that other forumists get theirs from stepping outside of the rational to share and speculate about Forteana - and we don't need to be told that's it's mostly bunkum!

Maybe you don't... Forum members seem to encompass a wide variety and participate for different reasons. Some people believe lots of ridiculous stuff without much thought. It does not hurt to be the voice of caution on occasion. The audience will regularly ignore that voice anyway.

If you are posting to a public forum, you have to assume that not everyone will get or agree with the perceived tone or position.

 

[blessmycottonsocks]

Apart from natural fluctuations in the Earth's magnetic field and the presence of significant ferrous deposits, apparently the presence of high-power electrical cables can also affect a compass.
I just checked on the National Grid's interactive map though and there are no cables shown in the vicinity of the Devil's Punchbowl. The only other thing I could think of was an electrified train track, but the SWR line from Guildford to Haslemere is over 2 miles away, so I discounted that.

 

[SimonBurchell]

Apart from natural fluctuations in the Earth's magnetic field and the presence of significant ferrous deposits, apparently the presence of high-power electrical cables can also affect a compass.
I just checked on the National Grid's interactive map though and there are no cables shown in the vicinity of the Devil's Punchbowl. The only other thing I could think of was an electrified train track, but the SWR line from Guildford to Haslemere is over 2 miles away, so I discounted that.

There is a large transmission mast on the west side of the Punchbowl, I don't know if that would affect a compass or not.

 

[blessmycottonsocks]

There is a large transmission mast on the west side of the Punchbowl, I don't know if that would affect a compass or not.

Good call. Power lines to the mast and to supply other local infrastructure such as the café and visitors' centre must run somewhere. But that would apply to every urban area too and, despite the presence of cell network masts and electricity cables, compasses still generally give accurate readings.

 

[Floyd]

There is a large transmission mast on the west side of the Punchbowl, I don't know if that would affect a compass or not.

Good call. Power lines to the mast and to supply other local infrastructure such as the café and visitors' centre must run somewhere. But that would apply to every urban area too and, despite the presence of cell network masts and electricity cables, compasses still generally give accurate readings.

Could it be that things just have to be in a particular configuration that would interfere with readings?

I mean a mast here, a cable there and another there, forming (say for eg) a triangle?

 

[charliebrown]

According to programs on the History Channel ( U.S. ) compasses spinning in the Bermuda Triangle is not that unusual.

My wife’s first cousin, the retired tug boat captain, who made extra money crewing private boats, claims when he was in the Bermuda Triangle and seeing the compass spin really “ freaked “ him out because this was against what he thought was normal.

Obviously, there is some magnetic force at play here.

Lloyd’s of London dismisses the Bermuda Triangle as myths saying saying statistically this area of the ocean is no different for mishaps.