Need Help with Possible WW1 Anti-Aircraft Site on South Coast of UK

[Westcliff]

Hi, first time poster today and hoping someone can help me with some research I am conducting at the moment. 

 

Here are photos of concrete plinth on land on the south coast of the UK. I believe it has a WW1 connection as one of the people responsible for the land it's on has shown me a letter from November 1917 titled "Anti-Aircraft Sites". The letter is written by a war department land agent who is proposing the following to those with an interest in the land. 
 

Quote

"place a small concrete base for height finding purposes on the land"

 

Based on that, and another letter from 1919 talking about removing barbed wire the location, we can assume the concrete plinth here was constructed between late 1917 and early 1919. 

 

On the photos below I have made notes. The black triangle shape is also drawn on by me to show the triangular indentation.

 

Myself and my 7 year old to help with perspective

 

 

Triangular indent on the top with 98cm length sides

 

 

Threaded bolt in the centre plus hole off centre (not sure if hole is deliberate or damage)

 

 

Square cut out on the side with evidence of electrics at top and possible socket at bottom

 

 

The cut out in the side has been said could have held a telephone by a local person. This could be a story that has evolved over time though. Like all of this though, there is no hard evidence yet to back this up that I have found, other than the evidence of wiring in the space. 

 

Interestingly, 300 metres from this area there was a WW2 Royal Observer Corps position, so evidently this land was a good strategic spot for this kind of activity (top of hill)... if in fact that's what this concrete is, and how it possibly relates to WW1.

 

Any comments appreciated, as would love to solve what this is. 

 

[Guest]

Good Morning, Westcliff-welcome to the Forum.    

 

    How intriguing!!   Might I ask a couple of daft questions about this?

 

1)  Is this beastie marked,say, on the 1" Ordnance Survey-either the current edition or previous?   It does look rather like a trig point used for OS surveying-  the triangle on the top suggests it might be that.

2) It looks as though it has subsided over time- Could you point out which is East,West,etc- and what lies in each direction?  Is it at the highest point locally?

 

     I live at the other end of Essex and spotting these old bits and pieces always comes as a pleasant surprise- Most of the parks across the east of London have some AA stuff in them -and always situated at the western end of parks-as it gives the best sighting for observation and AA fire across open ground. But that is for the second war.  Thus, a big clue is to work out from which way the enemy would have come  and how the construction you have might fit into a scheme of defence- the direction is always a very big clue as to what is what.

[Westcliff]

Thank you for the warm welcome! Let me get some detail together update the thread.

[Westcliff]

Rough estimates on North and South directions.

 

 

[Moonraker]

... 1)  Is this beastie marked,say, on the 1" Ordnance Survey-either the current edition or previous?   It does look rather like a trig point used for OS surveying-  the triangle on the top suggests it might be that.

2) It looks as though it has subsided over time- Could you point out which is East,West,etc- and what lies in each direction?  Is it at the highest point locally?

Welcome, Westcliff, and what an impressive first post, with some excellent photos.

 

By very minor coincidence, on  Saturday I glanced at a trig point in Oxfordshire and the grooves on the top were completely different, like this

 

 

And trig points were/are on higher ground.

 

It might be worthwhile looking at

 

https://maps.nls.uk/

 

where you should be able to find a 6in or even 25in map of the 1920s.

 

Good Luck!

[Guest]

12 minutes ago, Moonraker said:

By very minor coincidence, on  Saturday I glanced at a trig point in Oxfordshire and the grooves on the top were completely different, like this

 

   Very much agreed about trig. points-I have only ever climbed to look at one out of curiosity (Dorsmouth Rock in Plympton)  -but the 3 metal runners  shown in the pic. from Westcliff  were there for a reason-if only we could figure out what sort of gismo fitted into it's grooves. 

[Moonraker]

"The action of the anti-aircraft guns was of great assistance to our fighter squadrons."

 

(I'm guessing from his name that Westcliff is describing an installation in Southend, Westcliff being part of Southend.)

 

My uneducated guess: was the plinth a searchlight mounting?

 

Googling produces a number of peripheral websites - no doubt Westcliff has already checked them out?

[NigelS]

Looks similar to a searchlight pedestal at the Old Needles Battery on the Isle of Wight https://www.360cities.net/image/searchlight-emplacement-needles-old-battery-isle-of-wight-england  unfortunately the 3D imagery doesn't give anything to reference size wise - it is a big beast though; also  not sure that the single stud shown would have been sufficient to secure anything of any size effectively.    

 

EDIT: Could a searchlight be mounted at this position to scan over the sea? The one at the Needles was installed for that purpose not AA - it's roofed so wouldn't be useable for that purpose.

 

NigelS

Edited 5 January , 2021 by NigelS
additional note

[Guest]

Whatever this beastie was, the concrete pedestal rather annoyingly provides the clues for an answer- but does not pin it down.

 

1)   The reinforced concrete "pedestal" implies something that needed to be permanently fixed- and,at a guess, something that needed a level surface when it was built-which implies some degree of accurate measuring and,consequently, some piece of kit that did measuring.  Again, the need for a level base implies measuring that produced results measured as angles.

 

 

2) The  alignment of the mount lines on the beastie facing south again indicates some need for accurate measuring from a base point-so many degrees one way , so many degrees the other.

 

    OK, not OS theodolite positions  but perhaps something similar---  The only piece of kit that seems to fit is a Vickers Computer.  - a piece of kit designed the control the direction of fire of a bank of -yes, you've guessed it, Vickers machine guns.  Thus, an accurate measurement of vertical angle and lateral angle might allow multiple MG fire to be accurately guided.

 

   Hard to find a picture of the beastie but searching on Vickers Computer does throw up an interesting little article from Great war film stock taken by the US Signal Corps.

 

 

 

[Gunner Hall]

it looks very much like a spigot mortar plinth,  although without the usual convex top.   

 

The convex top ones were designed for the Second War, "Blacker Bombard"  Perhaps these were for another design of mortar /  search light  / weapon of last resort.  

 

For example  https://www.geograph.org.uk/photo/5594070 

 

https://fsgfort.com/fortfinder/poi/spigot-mortar-base-nuns-bridge-2/

[Guest]

16 minutes ago, Gunner Hall said:

t looks very much like a spigot mortar plinth,  although without the usual convex top. 

 

   Could well be-though if our colleague is actually from Westcliff, as his moniker betokens, it does seem decidedly unsporting to mortar bomb Southend- no matter how great the temptation. Just a thought...

[TEW]

Is there anything recorded on Heritage Gateway? This will included the Essex HER (local records) if that's the right county?

https://www.heritagegateway.org.uk/gateway/

TEW

 

[Westcliff]

Hi Guys, this is in Hampshire.

 

I don't believe it to be a Spigot Mortar base... plus... 

 

The evidence I have seen suggests it was built between late 1917 and early 1918 in a letter called Anti Aircraft Sites. The writer of the letter is requesting permission to:

 

"place a small concrete base for height finding purposes on the land"

Edited 6 January , 2021 by Westcliff

[Westcliff]

Frustratingly that's where the evidence ends.

 

In my photo you can see evidence of an electrical point and (possible) telephony. From what I have read about early AA systems from 1917, they could use telephony.

 

My thought was it could be part of LADA - London Air Defence Area, but I don't think that extended to Hampshire. - could be wrong, but the dates would stack up.

 

I've looked up height finders from this period, but can't find anything that might fit in the triangular area.

 

I then thought that perhaps it was repurposed in WW2, as there was a ROC position 300 meters away in the 1940s. However, if you look at an aerial shot of the land from WW2, there is no path leading from the ROC position to the concrete plinth - you would think there was if the ROC were using the concrete in the 1940s they would run a clear path to the concrete.... makes no sense for them not to run straight to it on a path over open land.

 

Edited 6 January , 2021 by Westcliff

[Gunner Hall]

11 minutes ago, Westcliff said:

Hi Guys, this is in Hampshire (Southampton area).

 

I don't believe it to be a Spigot Mortar base... plus... 

 

The evidence I have seen suggests it was built between late 1917 and early 1918 in a letter called Anti Aircraft Sites. The writer of the letter is requesting permission to:

 

"place a small concrete base for height finding purposes on the land"

Ah, yes.  I remember reading that..    Went off on a tangent.

Edited 6 January , 2021 by Gunner Hall

[Westcliff]

The Needles searchlight looks very similar in shape:

 

It could also be possible for there to be a triangular shape under the circular base, in order to limit the rotation of the searchlight.

 

However, the concrete in my example is on top of a hill, not overlooking coast, so would make no sense for them to limit the rotation.

 

 

 

 

Edited 6 January , 2021 by Westcliff

[Guest]

Would you by chance have the letter asking for permission?  If it is on headed notepaper and follows the normal pattern of having at least one reference number on it, then it may be possible to backtrack to other records.

  Everything so far suggests it is some form of range finder 

[Westcliff]

Would you by chance have the letter asking for permission?  If it is on headed notepaper and follows the normal pattern of having at least one reference number on it, then it may be possible to backtrack to other records.

  Everything so far suggests it is some form of range finder 

Unfortunately not, only seen it and literally copied the words down. It was handwritten, not headed. The writer addresses himself as:

 

Assistant War Dept. Land Agent

 

PS:  I do apologise about being vague on precise location. Those responsible for the land are not keen the location being shared at this point.

[Guest]

2 hours ago, TEW said:

Is there anything recorded on Heritage Gateway? This will included the Essex HER (local records) if that's the right county?

https://www.heritagegateway.org.uk/gateway/

TEW

 

 

    I had a look at Heritage and local authority listings for the Southend area but it is light for WW1/WW2 bits and pieces.  This is still hit and miss round the country. My home area of Plymouth is well covered and as a bookseller one of my old customers was the English Heritage officer responsible for those listings. Where I live now, in "Metropolitan" Essex has plenty of stuff but it is hit and miss as to what has been noted,let alone listed. For instance, a trip on the tube-Central Line-can give a great view of a run of dragons teeth- while a sunken rose garden in a local park was made from an old Ack-Ack gun emplacement from WW2.  Simple once you know what it is but it took another of my customers who had grown up in the same road in which I lived to tell me-Not picked up by local authority for local listing.

   It's still worth asking if there is "local listing"-if there is none or it does not get listed, then at least it gets known.

[Westcliff]

Ah... the Needles searchlight base is much smaller.

 

 

[TEW]

I've also checked the area with Heritage Gateway with no luck, although they have a Southampton HER they don't have a Hants HER.

 

Coverage of monuments from different eras could be down to the interests of county archaeologists, Devon does have strong coverage for WWII items.

 

Also checked a lidar map but can't zoom in enough to the wooded area to pick anything out.

 

I won't share the location!

TEW

[Westcliff]

Thanks, I really appreciate your help.

 

I am determined to get to the bottom of it, so when I do I will come back here and tell you all what I've found.

 

Will be in touch.