Detecting Tunnellers with Dried Peas

In an earlier post I wrote about a peculiar technique allegedly recommended hundreds of years ago to detect buried explosives   I have been on the hunt for more very early explosive devices and EOD techniques.  I’m currently deep into a startling book published in 1590. Forgive me but I’m going to keep the name and author of the book to myself until I’ve finished working out what it says.

For now here’s an intriguing technique from the book for detecting subterranean tunnelling such as was used for mining the ramparts and walls of fortified castles. Tunneling is of course still used by all sorts of terrorists, and others. Apologies if I have mistranslated any of the description from quite archaic (for me) language. For ease of reading here’s my explanation of a couple of the words which may not be familiar to you, followed by the full description:

“lattine bason”  = tin basin, or tin pan

“peason” = dried peas

“woll” = wool

As touching thus for to know whether there be any undermining in the ground, and where that they be, it is thus knowne: – Take a lattine bason, and goe unto the place that you doo suspect that underminers may bee, and set that bason uppon the ground, and then put five or sixe peason in that bason, and if that there bee any underminers neere at hand, then at everie stroke that they are in the ground doo make with their tooles, the pease will make a jarre in the bason; and also the effect will the more appeare, if that you doo binde a sackfull of woll as hard as you can, then setting the bason with pease uppon that, you shall heare every stroake that is made in the ground, and this is one of the best things that may be devised to be placed in any place, for to knowe where that underminers be.

I find the counter-intuitive idea of tightly bound wool to aid the “coupling” of the tin pan with the ground to be very interesting. If I had anything other than tinned peas in the house I’d do an experiment right now…

More to follow on other fascinating matters from this book in weeks to come.

An innovative buried IED detection technology from 1400

I’m slowly researching a number of old military technology books (if I can describe them as that) written several hundred years ago. Every so often I come across something intriguing. Here’s today’s.

Conrad Kyeser lived between 1366 and about 1405. He was born in Eichstadt in Southern Germany but lived for a time in Prague. I have referenced his book “Bellifortis” in my last post. The book was written in (poor) Latin and contained many illustrations. Kyeser clearly copied a number of other military technology books, but there was also new material. It exists today with several versions. Some of the technology discussed is remarkable for the time of writing – paddle powered boats able to move against a current, diving suits with some form of stored air for breathing, and a variety of explosive devices, rockets and multi-barrelled revolving firearm systems.  The rocket discussion includes remarks on the need for a combustion chamber (described as a “seele” or hollow in the propellant), and that the rocket cylinder/case must be gas-tight.

But here’s something very interesting – a buried IED detection technology. Kyeser describes burning a resin to create a volume of dense thick smoke, contained under an inverted tub. Once a dense cloud is formed the tub is lifted off and the dense smoke allowed to spread across the ground of an area where a buried explosive device is suspected. Kyeser claims that if the smoke rises at any point, that is an indicator of disturbed earth, and the potential that an explosive device has been buried there.

Now that’s an interesting idea, but on the face of it, I don’t have any particular belief that it might work.  If a heavy gas rises it perhaps could be due to convection, but why would disturbed earth have convection , I assume associated with a thermal energy release from disturbed ground?  I can imagine certain theoretical scenarios where a dark soil is exposed as the device is buried and that causes slightly more solar energy to be absorbed, and then released, but that’s perhaps stretching it a bit. Maybe a buried barrel of gunpowder previously stored in a building would retain its heat long enough when compared to the cold earth in which it was buried and that could cause some convection for a short time.  I wonder how long….

I welcome any readers who might have a better explanation, email me at the email address explained above right.

EOD Equipment 1573 and 1971

I have finally found a picture of a wheeled EOD shield from 1971 – courtesy of RLC Museum. Compare these two largely similar tools, the first from 1573, and the second from 1971 – 402 years apart. I believe the shield was used operationally in Hong Kong in the sixties, and quickly went out of service after limited use in Ulster in the early seventies.


circa 1573

 

EOD-Equipment-1573-and-1971-1971
circa 1971

My earlier post on the subject of historical ROV’s is here.

1894 Bomb Disposal Techniques

I have blogged before at an IED disposal system and associated organisation set up in Paris, France in the late part of the 19th century.  In my earlier blogs I have discussed the “containment vehicle” used to transport suspect IEDs to one of four disposal sites set up around Paris, and the use of hydraulic presses to dismantle IEDs once taken thefre.

I have recovered a little more detail about both, in some reports written by Colonel Majendie, the British explosives expert, who visited Paris in early 1894 and considered the techniques being used , adapting some for use in London.

Firstly the vehicle and containment system, originally material posted here.   Here now is Majendie’s description:

 

The bomb is deposited on a quantity of wood shavings or similar elastic material in the body of the phaeton….At one time the idea was entertained of constructing a bomb proof cart for this purpose – or at any rate a cart by which by mans of iron shields would prevent the lateral dispersion of fragments should the bomb unfortunately explode in transit. But the idea was abandoned in view of the fact that infernal machines in some cases contained very large charges of explosives (e.g the machine which exploded at the Rue de Clichy contained between 50 and 60 lbs), and of the considerations, 1st. that the cart which would resist the explosion of such a charge would be proportionally inconvenient to bring into action, besides attracting much attention… and that in the event of a bomb containing a charge in excess of what the cart was calculated to resist exploding therein, the iron and stout structure of the cart itself would probably seriously aggravate the effect.  

Majendie goes on to discuss that the presses available at each of the four disposal sites (which are pictured i the earlier post referenced above) which often succeeded in dismantling the IEDs without them exploding, but on occasion when an explosion did occur, its effect was usually “greatly diminished” by cracking of the outer shell.  Interestingly Majendie also reported three other techniques used during EOD operations:

a. Sometimes small dynamite charges were used to open the container of a bomb.

b. The French also used a mechanical device with three movable arms, or “holders” into which IEDs of different sizes can be fixed and lowered into a bath of mercury. Some devices were sealed with the use of solder and by immersing that part in mercury, for about 24 hours, caused the tin in the solder to dissolve breaking any soldered seal.

c. if the team attending the site of an incident felt it too dangerous to move they would “blow in place”. Majendie disagreed with this approach and recommended a degree of risk to avoid inadvertently seconding and supplementing the anarchist’s intentions.

As a result of the visit, Majendie developed the small, light handcart for transporting devices, that I showed in an earlier post here. The first of London’s disposal facilities was set up in 1894 on Duck Island , with others planned at Hyde Park, the Tower of London and in some circumstances a facility at Woolwich.   Later, in 1895, a truck was provided for transporting devices to the disposal facility by the War Office.  Two years later in 1896, the French authorities were using the first X-ray imaging systems to examine suspect IEDs.

Russian Partisan EOD search, 1942

I’ve found an interesting book, “The Partisan’s Companion“, a guerilla warfare manual produced by Russia in 1942. There’s a small section on EOD search for German mines and booby traps which is interesting.

Remember the fascists use mines widely and employ them with cunning and trickery. Quite often they leave various lures in plain sight and connect them to mines. You should be careful and wary of them.

Do not enter a house which has been left by the Germans until you have inspected the ground around it, The stair steps of the porch, doors, windows, floor boards and various household objects – all of them could be connected to mines.  Any attempt to move them or even a simple touch could produce and explosion.   Use long rope and a grapnel to open the door of such a house.

After entering the house – thoroughly inspect it. First, do a visual inspection, looking for the revealing signs of mines: fresh spots in the wall’s plaster, evidence of disturbing the bricks in the walls or stove, fresh scratches on the floor. Also check the electrical wires – see if there are any devices connected to them. If you find suspicious areas- check them more thoroughly.

Try to avoid all kinds of twine, rope and wire in the forest, on the roads and in the houses. They could be linked to mines. Be careful around places which show some disturbance to their uniformity.For example: small lumps of dirt on grass warn you about digging at that site. Be careful not to pick up a rifle or other weapon left behind by the Germans, especially if it is in a highly visible spot. Remember that the Germans sometimes even put mines on the corpses of their soldiers and officers.

The manual then goes on to describe an interesting technique for finding buried clockwork timed mechanisms attached to mines, using a “water stethoscope”.  A water bottle is filled almost to within a few centimeters from the top, and a glass tube inserted through the stopper. Put a rubber hose onto the outside of the tube. Then plant the bottle in the ground, with the surface of the water in the bottle level with the ground. Place the end of the hose to your ear and if there is a buried clockwork device nearby you will hear it.

That sounds like an interesting technique – I’ll have to give it a try.

 

 

Close Me
Looking for Something?
Search:
Post Categories: