# What does BSW^D mean on old maps?

**URL:** <https://boards.straightdope.com/t/what-does-bsw-d-mean-on-old-maps/787265>\
**Category:** Miscellaneous and Personal Stuff I Must Share\
**Created:** [May 23, 2017, 10:30am UTC](https://boards.straightdope.com/t/what-does-bsw-d-mean-on-old-maps/787265 "2017-05-23T10:30:27Z")\
**Posts on this page:** 18\
**Page:** 2

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**Author:** ![RobDog](https://avatars.discourse-cdn.com/v4/letter/r/f07891/32.png) [@RobDog](https://boards.straightdope.com/u/RobDog)\
**Post date:** [May 23, 2017, 8:42pm UTC](https://boards.straightdope.com/t/what-does-bsw-d-mean-on-old-maps/787265/21 "2017-05-23T20:42:03Z")

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> [@Malden\_Capell](#):
>
> OK, follow-up question: why would the War Dept have boundary stones here? Is it a standard thing for all coastline?
> 
> I know Tilbury fort is directly opposite…

There’s a set of boundary stones encircling the rifle range on the south bank at the far east of the map, so that’s one possible reason.

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**Author:** ![MrDibble](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/mrdibble/32/114_2.png) [@MrDibble](https://boards.straightdope.com/u/MrDibble)\
**Post date:** [May 23, 2017, 8:42pm UTC](https://boards.straightdope.com/t/what-does-bsw-d-mean-on-old-maps/787265/22 "2017-05-23T20:42:22Z")

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> [@Malden\_Capell](#):
>
> OK, follow-up question: why would the War Dept have boundary stones here? Is it a standard thing for all coastline?

Not just the coastline - they were used on [survey benchmarks](https://en.wikipedia.org/wiki/Benchmark_(surveying)) for \*all \* [Ordnance Survey](https://en.wikipedia.org/wiki/Ordnance_Survey) activities, from what I can tell. In the 1800s (Napoleonic Wars) , the entire country was mapped (as a quasi-military activity, hence the Ordnance moniker, which originated in the Scottish wars)

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**Author:** ![Dave.B](https://avatars.discourse-cdn.com/v4/letter/d/9f8e36/32.png) [@Dave.B](https://boards.straightdope.com/u/Dave.B)\
**Post date:** [May 23, 2017, 8:46pm UTC](https://boards.straightdope.com/t/what-does-bsw-d-mean-on-old-maps/787265/23 "2017-05-23T20:46:47Z")

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> [@Malden\_Capell](#):
>
> How about that! Let me know - I’m buying a house in the area 😃

The flood defences along the south bank of the Thames need raising slightly now, again sometime in the 2040s, then again in the 2070s. Providing this happens you should be OK, but (assuming they are still responsible in 20/50 years) will the Environment Agency and Kent County Council (as Lead Local Flood Authority) be able to fund it? My gut feeling is yes, as it’s “London”, but even if I was a betting man, I wouldn’t put house money on it.  
If private flood defences are an option for you, I would look into it. You can get very discrete floating barriers installed at your doors, and clever air bricks that seal up again by floating. Expensive, but you will reap some money back on your home insurance.  
Also, those flood defences are designed to protect against a 1 in 100 year flood event. A 1 in 200 year event could happen tomorrow.  
Not trying to put you off buying, but, if you haven’t already, maybe speak to some home insurers and also the Environment Agency.

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**Author:** ![Mk\_VII](https://avatars.discourse-cdn.com/v4/letter/m/5f9b8f/32.png) [@Mk\_VII](https://boards.straightdope.com/u/Mk_VII)\
**Post date:** [May 23, 2017, 9:05pm UTC](https://boards.straightdope.com/t/what-does-bsw-d-mean-on-old-maps/787265/24 "2017-05-23T21:05:30Z")

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> [@Malden\_Capell](#):
>
> OK, follow-up question: why would the War Dept have boundary stones here? Is it a standard thing for all coastline?

The land up to the high water mark belongs to the W.D. and comes under the relevant Military Lands Act. They may have acquired it as part of the military barracks to the south, and laid it out as sports fields etc. In an era before Land Registry there was probably a legal requirement to mark the WD’s boundary so that people did not encroach on it.

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**Author:** ![Malden\_Capell](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/malden_capell/32/5274_2.png) [@Malden\_Capell](https://boards.straightdope.com/u/Malden_Capell)\
**Post date:** [May 23, 2017, 10:12pm UTC](https://boards.straightdope.com/t/what-does-bsw-d-mean-on-old-maps/787265/25 "2017-05-23T22:12:48Z")

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> [@Dave.B](#):
>
> The flood defences along the south bank of the Thames need raising slightly now, again sometime in the 2040s, then again in the 2070s. Providing this happens you should be OK, but (assuming they are still responsible in 20/50 years) will the Environment Agency and Kent County Council (as Lead Local Flood Authority) be able to fund it? My gut feeling is yes, as it’s “London”, but even if I was a betting man, I wouldn’t put house money on it.  
> If private flood defences are an option for you, I would look into it. You can get very discrete floating barriers installed at your doors, and clever air bricks that seal up again by floating. Expensive, but you will reap some money back on your home insurance.  
> Also, those flood defences are designed to protect against a 1 in 100 year flood event. A 1 in 200 year event could happen tomorrow.  
> Not trying to put you off buying, but, if you haven’t already, maybe speak to some home insurers and also the Environment Agency.

Thanks, good advice. Surveys came back last week indicating the house is just outside the flood risk zones - just. We’ll look into flood insurance, and defences sound a wise idea.

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**Author:** ![usedtobe](https://avatars.discourse-cdn.com/v4/letter/u/ec9cab/32.png) [@usedtobe](https://boards.straightdope.com/u/usedtobe)\
**Post date:** [May 23, 2017, 11:37pm UTC](https://boards.straightdope.com/t/what-does-bsw-d-mean-on-old-maps/787265/26 "2017-05-23T23:37:51Z")

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If not posted:

> **[History and Geography of Europe](https://euratlas.com/index.html)**
>
> Historical atlas of Europe. Maps of mountains, rivers, cities and countries of Europe and of the World. 2000 pictures of towns and landscapes. Antique digitized maps. Digital vector maps and georeferenced vector maps, educational softwares.

Europe geography and history

Lots of fighting

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**Author:** ![Dave.B](https://avatars.discourse-cdn.com/v4/letter/d/9f8e36/32.png) [@Dave.B](https://boards.straightdope.com/u/Dave.B)\
**Post date:** [May 23, 2017, 11:40pm UTC](https://boards.straightdope.com/t/what-does-bsw-d-mean-on-old-maps/787265/27 "2017-05-23T23:40:58Z")

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> [@Malden\_Capell](#):
>
> Thanks, good advice. Surveys came back last week indicating the house is just outside the flood risk zones - just. We’ll look into flood insurance, and defences sound a wise idea.

Good luck with it. I had significant input in the survey for the EA’s flood maps after the floods 17 years ago in Devon and Cornwall. A lot of work went into them and they were _very_ accurate.

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**Author:** ![Senegoid](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/senegoid/32/6606_2.png) [@Senegoid](https://boards.straightdope.com/u/Senegoid)\
**Post date:** [May 24, 2017, 5:17am UTC](https://boards.straightdope.com/t/what-does-bsw-d-mean-on-old-maps/787265/28 "2017-05-24T05:17:13Z")

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> [@Dave.B](#):
>
> Well this is a bizarre coincidence. I’ve just spent the last couple of weeks writing a flood risk assessment for the gate across the entrance to that very canal basin.

Well, SOMEONE had to do it.

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**Author:** ![stillownedbysetters](https://avatars.discourse-cdn.com/v4/letter/s/41988e/32.png) [@stillownedbysetters](https://boards.straightdope.com/u/stillownedbysetters)\
**Post date:** [May 24, 2017, 3:45pm UTC](https://boards.straightdope.com/t/what-does-bsw-d-mean-on-old-maps/787265/29 "2017-05-24T15:45:24Z")

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> [@ThelmaLou](#):
>
> I love maps! If Google Maps/Earth had existed when I was a kid, I’d have never left the house!

What a shame I didn’t encounter you 20 years ago. I could have introduced you to our neighbor, who was a cartographer. He loved to talk about his work…in great detail. lol Perhaps too much for most social occasions, but it would probably have been fascinating for you. 😊

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**Author:** ![idreamofthought](https://avatars.discourse-cdn.com/v4/letter/i/53a042/32.png) [@idreamofthought](https://boards.straightdope.com/u/idreamofthought)\
**Post date:** [June 17, 2019, 12:56pm UTC](https://boards.straightdope.com/t/what-does-bsw-d-mean-on-old-maps/787265/30 "2019-06-17T12:56:02Z")

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they were indeed war department stones. there was one in my back garden and a picture is available here  
[http://www.medwaymemories.co.uk/?page\_id=278](http://www.medwaymemories.co.uk/?page_id=278)

this stone marked the end of military land, there was an army camp build between the wars here but now gone. The army land was used from Napoleonic times.  
The stone here also marks a parlimentary division (or marked) and even more so the MARK for a man of kent/kentish man. rainham mark

BSW^D

wd = war depardment  
Bs = boundary stone

^  
is the OS arrow

> **[Broad arrow | Use for British Government property](https://en.wikipedia.org/wiki/Broad_arrow#Use_for_British_Government_property)**
>
> The broad arrow was used in England (and later Britain), apparently from the early 14th century, and more widely from the 16th century, to mark objects purchased from the monarch's money, or to indicate government property. It became particularly associated with the Office or Board of Ordnance, the principal duty of which was to supply guns, ammunition, stores and equipment to the King's Navy.

depicting 'Get Orf My Land" (or something like it!)

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<div class="post-metadata">

**Author:** ![VOW](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/vow/32/3043_2.png) [@VOW](https://boards.straightdope.com/u/VOW)\
**Post date:** [June 17, 2019, 3:45pm UTC](https://boards.straightdope.com/t/what-does-bsw-d-mean-on-old-maps/787265/31 "2019-06-17T15:45:20Z")

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GAWD, I’m going to have fun with all the data in this thread! I made maps for over twenty years for CalTrans! Researching historical maps was the best part of the job!  
~VOW

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**Author:** ![Just\_Asking\_Questions](https://avatars.discourse-cdn.com/v4/letter/j/ba9def/32.png) [@Just\_Asking\_Questions](https://boards.straightdope.com/u/Just_Asking_Questions)\
**Post date:** [June 17, 2019, 5:32pm UTC](https://boards.straightdope.com/t/what-does-bsw-d-mean-on-old-maps/787265/32 "2019-06-17T17:32:10Z")

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> [@ThelmaLou](#):
>
> I love maps! If Google Maps/Earth had existed when I was a kid, I’d have never left the house!

Then why would you need maps?

🙂

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**Author:** ![PatrickLondon](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/patricklondon/32/4422_2.png) [@PatrickLondon](https://boards.straightdope.com/u/PatrickLondon)\
**Post date:** [June 18, 2019, 6:14am UTC](https://boards.straightdope.com/t/what-does-bsw-d-mean-on-old-maps/787265/33 "2019-06-18T06:14:38Z")

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> [@Just\_Asking\_Questions](#):
>
> Then why would you need maps?
> 
> 🙂

So that the imagination can travel?

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**Author:** ![Elendil\_s\_Heir](https://avatars.discourse-cdn.com/v4/letter/e/7cd45c/32.png) [@Elendil\_s\_Heir](https://boards.straightdope.com/u/Elendil_s_Heir)\
**Post date:** [June 21, 2019, 7:50pm UTC](https://boards.straightdope.com/t/what-does-bsw-d-mean-on-old-maps/787265/34 "2019-06-21T19:50:48Z")

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“Bondage, Sadism, Whipping Up Dere”

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**Author:** ![Sapper](https://avatars.discourse-cdn.com/v4/letter/s/f05b48/32.png) [@Sapper](https://boards.straightdope.com/u/Sapper)\
**Post date:** [October 27, 2024, 9:34pm UTC](https://boards.straightdope.com/t/what-does-bsw-d-mean-on-old-maps/787265/35 "2024-10-27T21:34:03Z")

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Old maps provide the means to travel into the past. What you are looking at comes alive. I’ve been looking at a 1909 map of where I was in 1959. And the memories come flooding back.

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**Author:** ![Sapper](https://avatars.discourse-cdn.com/v4/letter/s/f05b48/32.png) [@Sapper](https://boards.straightdope.com/u/Sapper)\
**Post date:** [October 27, 2024, 9:39pm UTC](https://boards.straightdope.com/t/what-does-bsw-d-mean-on-old-maps/787265/36 "2024-10-27T21:39:02Z")

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Even though your post is seven years old, it has today provided the answer to a question that has just arisen from looking at an OS map dated 1909. The British army had barracks at Bordon in Hampshire, England, at the time - hence a large number of BS and BM (Bench Mark?) letters dotting the area.

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**Author:** ![purplehorseshoe](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/purplehorseshoe/32/2996_2.png) [@purplehorseshoe](https://boards.straightdope.com/u/purplehorseshoe)\
**Post date:** [October 27, 2024, 9:46pm UTC](https://boards.straightdope.com/t/what-does-bsw-d-mean-on-old-maps/787265/37 "2024-10-27T21:46:58Z")

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> [@Sapper](#):
>
> Even though your post is seven years old, it has today provided the answer to a question that has just arisen from looking at an OS map dated 1909.

1a.) Welcome to our silly little community! Please be welcome.

2b.) The fact that this thread helped some random person years after the fact is part of why some of us stick around.  
Also we like to nitpick, argue the stoopitest piddly nonsense, and occasionally, help each other out.

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<div class="post-metadata">

**Author:** ![VOW](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/vow/32/3043_2.png) [@VOW](https://boards.straightdope.com/u/VOW)\
**Post date:** [October 29, 2024, 1:21pm UTC](https://boards.straightdope.com/t/what-does-bsw-d-mean-on-old-maps/787265/38 "2024-10-29T13:21:28Z")

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Boundary stones mark property corners, and were typically placed by surveyors. Nowadays, brass or aluminum caps are used.

Bench marks (or stones) identify elevation at that point.

So to completely clear up the mystery, **BSW^D** means "Boundary Survey War Department.

~VOW

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