You can contact me at rogercdavies(atsquiggle)

This blog has evolved into a review of historical and modern explosive devices, and responses to them. Links are drawn between historical activity and similar activity in the world today. Mostly I focus on what are now called IEDs but I have a loose personal definition of that and wilingly stray into discussions of more traditional munitions, the science and technology behind them, tactical employment and EOD responses. Sometimes it's just about interesting people in one form or another. Comment is welcome and encouraged but I do monitor it and reserve the right to delete inappropriate stuff. Guest posts are always welcome. Avoid any stuff that makes the enemy's job easier for them.


Entries in 1700-1800 (9)


The language of IEDs

What we now call Improvised Explosive Devices have had different names over the centuries that they have been used. Here's one you may not have heard of.  The word "caisson" has a range of meanings derived from the "sealed box" of its original meaning. Today a caission is associated with either the ammunition box used in support of an artillery piece, or a sealed box like structure sunk in water to allow engineering work to take place.  But in 1778 "caisson" had this meaning, according to a military dictionary published that year:


Clocks, locks, energy and initiation

I’ve written before about the evolution of gunlocks, from matchlocks, through wheel-locks to snap-huances and then flintlocks because although these initiation systems were designed to initiate firearms they also enabled initiation mechanisms for explosive devices.  This post returns to that subject to discuss a couple of more elements to that story that I find interesting, namely engineering development and some fundamental issues about “energy” chains that apply both to these firearms systems and explosive devices.  In this post I have made some generalisations and simplifications in my description of the technology - forgive me, but otherwise the post turns into a book and neither you or I have time for that.                                                                      
Firearm initiation systems, and in parallel explosive initiation systems, are about initiating a quantity of explosives at a time that the operator chooses.  Thus, in the simplest of all firearm systems, a burning “match” is placed in contact with a small quantity of blackpowder in a “touch-hole” which then initiates a larger amount of blackpowder in the barrel of a gun.   This system worked for hundreds of years in the cannons you see fired in all the movies.                                                                                                                                                
The gun is aimed and the application of the burning “fuse” simply initiates the blackpowder.  The energy in the arm of the man holding the fuse, and the energy in the already burning fuse is enough to initiate the stored chemical energy in the blackpowder in the barrel.                                                                                                                                                                                                                                                               
But in a small firearm there’s an issue of the man pointing the gun and initiating it at the same time. Generally these firearms were pretty large and required two hands to point at a target.  So quite often the firearm was supported with a crutch allowing the firer to point it with one hand, sight the barrel with an eye at a target and use the “spare hand” to place the burning fuse on the touch hole. 
Firing an early firearm without a trigger and serpentine
But let’s face it, that’s a bit fiddly. The touch hole is small and it might be a bit awkward. The firer is concentrating on doing two things, keeping the target in line and finding a small hole with the burning fuse in one hand.   So, with some very simple engineering the matchlock was developed.    All that happened was that a simple S shaped lever was introduced onto the body of the firearm. One end of the lever held the burning fuse in  a specific position, the centre of the “s" shaped piece of metal was a pivot joint and the bottom end of the s was pulled with one finger.  The placement of the s shaped lever (a “serpentine) ensured that the burning match always found the touchhole or the pan at the entrance to the touch hole, and the firer could use two hands to aim the firearm, concentrate on the target and just use a finger to pull the “s" shaped piece of metal.
A very early, simple matchlock arquebus
 Now , manufacturing such a firearm was pretty simple, and within the engineering skills of the average door-lock manufacturer of the 15th century which simply used levers and pivots.   So matchlock firearms were relatively easy to manufacture and relatively cheap. Matchlocks continued to be produced from the 1400s for about 250 years.  I think this is important to understand - although better technology was invented in a series, starting in the early 1500s, match-locks remained a simple and cheap firearm and so were the most common at least until well in to the 1600s.
A nice image of a Japanese matchlock mechanism showing a pan cover
Now, there are some operational weaknesses with the simple matchlocks.  In the simplest of all matchlocks the pan or the entrance to the touchhole  is permanently exposed to the elements. So in poor weather the firearm simply won’t work.  Also the glowing match gives away both the position of the firer and the nature of their weapon.   Both these weaknesses were partially addressed.  Firstly a mechanism of a sliding or levered cover to the Pan or the entrance to the touchhole was developed, requiring some more intricate engineering so when the serpentine was moved then a cover was moved out of the way allowing the match access to the pan.  A bit complex.  Some attempts, too, were made to hide the burning match in a box, but not very effectively. Burning fuse also, by the way, made the weapon unsuitable for those guarding stores of ammunition.  So in the early 1500s the wheel-lock was developed.                                                                                                                    
In large part the wheel-lock invention was enabled by advances in engineering, and specifically advances in engineering from clock making.  On a fundamental level, the wheel-lock utilises, for the first time in a firearm, “potential energy” in a spring.   A wheel-lock, consists of a steel wheel, which has a small chain wrapped around its axle. The wheel is rotated with a spanner, this wraps the chain around the axle and the other end of the chain is attached to a spring.  Thus when the wheel is rotated it induces a potential energy into the spring. The spring is then held by a trigger. A second spring is then set up to hold the serpentine. In this case the serpentine doesn't hold a burning fuse, but a small lump of iron pyrites.  The spring acting on the serpentine holds the pyrites in contact with the rim of the steel wheel which usually has grooves on its circumference and some small notches to encourage friction.  When the main spring holding the chain attached to the wheel is released by pulling the trigger, the steel wheel rotates and, because it is in contact with the iron pyrites, sparks are formed.  The sparks initiate blackpowder in the pan.
So we have the potential energy in the spring, making kinetic energy in the wheel , which initiates chemical energy in contact with the pyrites, which initiates the chemical energy in the blackpowder, which converts to kinetic energy in the projectile, and that kinetic energy is transfered t o the target t cause damage.  A nice little chain, but one which requires a significantly more detailed engineering capability than a match-lock.                                                                                                         
The wheel-lock however has several advantages.   It is safer, in that safety catches can be applied to both the serpentine and the wheel.  The presence of a firearm is not given away by the burning fuse.  It can be prepared well in advance of use (if the springs don’t deform as some where liable to)  The firearm can be concealed. Since it is possible to conceal, the firearm was then made smaller, and so the pistol appeared for the first time, able to be held about a person, and the same person could indeed carry two or three wheel lock pistols. Since this is a blog about explosive devices, then of course the wheel-lock became a potential initiator for IEDs - the device could be hidden and initiated at a point of the firers choosing, perhaps say with a string to the trigger or a potential booby trap switch. IEDs are more suited to initiation by potential energy.
But now we have economics at play. The high level of engineering and therefore cost required for a wheel-lock would make it usually unsuitable for a one-time-use in an IED, although possible.   Only the rich could afford wheel-locks.  So wheel-locks and match-locks existed side by side for decades and indeed for at least 150 years. The economics of the engineering had some other interesting implications.  Matchlocks are simple utilitarian devices usually without decoration through the 16th century. Wheel-locks however, bought by the rich became covered in ornate art, and became models of fine engineering and artistic excellence.  Here’s some images of highly decorative wheel locks.
The fact that wheel-locks were used by the rich also had an effect on the manner in which warfare was conducted.   Ordinary infantrymen could not afford wheel-locks but the aristocratic and rich cavalry could. Cavalry tactics then evolved to make benefit of the capabilities that two or three wheel locks could provide. The cavalry galloped forward to a point within range of their wheel-locks, fired, and galloped back.   The tactics of cavalry using wheel-locks then had an impact on the types of horses and armour being used by the military. The huge horses required for armour encumbered cavalry with lances were replaced with smaller, quicker more agile horses. This perhaps lead, by connection, to the evolution of horse racing and blood stock management.   The armour, designed to to defeat the weapons of the medieval horseman was discarded - armour could be produced to protect against the bullets fired from wheel-locks but frankly it was too heavy.  So the nature of warfare rapidly evolved.  One could say that the nature of warfare evolved over the period of between 1500 and 1620 entirely because of the initiation system moving to a potential energy storage device (a spring) for the initiator rather than a chemical energy storage initiator (the burning match).                                                              
Subsequent evolutions of the gun-lock technology brought together the principle of a potential energy store (from the springs in the wheel-lock), with simpler engineering requirements.   I think that the spring-held serpentine of the wheel-lock got people thinking. Firstly pyrites wasn't always a solid enough material to hold reliably in the jaws of the serpentine, and indeed the spring holding the pyrites wasn’t designed to cause the pyrites to impact with the steel wheel, just hold it against it.  I think that the metallurgy of springs improved throughout out the 16th century.  A powerful spring could cause a flint to strike a steel firmly and reliably enough to set a spark - earlier technology wouldn't allow that - the springs would break or the springs would deform very quickly. But the evolution of clocks and associated engineering developed through the 16th century so that steel suitable for using in springs evolved.  All of a sudden there was a metal available that could be used in a  spring that could force a serpentine holding a flint hard enough to cause sparks. The “snaplock” then developed in about 1540 utilised the same serpentine used in the match-lock and wheel-lock, but this time powered by a strong spring to strike a “steel” to cause sparks - subsequent developments of the snap-huance and then the flintlock were simply improvements on that design, improving its reliability and weather protection.  Essentially then in energy terms, the potential energy inherent in the spring that powered the wheel in the wheel-lock was changed to potential energy in the main-spring of the flintlock. Crucially though the engineering required of the flintlock was still considerably simpler than the technology used in the wheel-lock. Flintlocks could be pretty much mass produced while wheel-locks remained the product of a highly skilled craftsmen. As an aside, the engineering tolerances required of the wheel of the wheel-lock needed to be much tighter than the engineering tolerances in a flintlock. In a wheel-lock the wheel rotates through a slot in the “pan” and if the slot is too big then the gunpowder falls through it.   The fact that flintlocks used potential energy , but were also cheap and able to be mass produced means that they became attractive to use in “one time use” IEDs such as this device . The first mine , Samual Zimmerman's "fladdermine" also use a flintlock mechanism.                                                                                                                                              
It is clear from reading up about the history of clock development that many of the principles of engineering in clocks developed during the period of about 1550 - 1750 were subsequently applied to the production of munitions fuses. There’s probably another blog (or book!) to be written about that. 



18th Century TPU, 19th Century Grave Robbers

I've blogged before about the use of flintlocks and other gun-lock mechanisms used as initiators in IEDs between the end of the 16th century and the middle of the 19th century.   Some recent digging has made me think that the integration of a timing mechanism with a flintlock mechanism was a widely used system, perhaps not regularly within an IED but widely enough that it's use must have been well known, even if only as a potential initiation system.  Here's some images of a couple of peculiar alarm clocks which I think make the point well. The operator sets a time on the clock which when reached released a spring loaded trigger on a flintlock.  A small amount of powder is then initiated which also ignite the wick of a candle which then by a linked spiring stands up in the box. These are I think from the period 1715- 1740 or thereabouts. Nowadays we'd call these a Time and Power Unit (TPU)

 I have also found a "set gun" which attached a flintlock to a tripwire, used as a deterrent for both for both poachers and grave robbers. Here's an image of one of these.  

To be clear I'm not suggesting any of these are IEDs, just that such a mechanism could have been used at the tme to initiate explosive devices.  The set guns were outlawed eventually but in 1878 an inventor, Mr Clover of Columbus, Ohio then came up with a "coffin torpedo" to deter grave robbers who opened a coffin with something like a shotgun cartridge, initiated by the opening lid.  "Torpedo" was the name given to IEDs at that time.   

In 1881 a Mr Howell invented two "Grave Torpedos", much more like IEDs and images from the patent application is shown below. These were much more like an American Civil War land mine, placed on top of a coffin with a plate above it, designed to be initiated when the grave robbers dug down.

These were effective - a grave robber was killed by the device and an accomplice wounded: 



How gun locks were used in IEDs for over 250 years

When I started my research into historical IEDs a few years ago, I came across references to “gun locks” used as initiation mechanisms. The “gun locks” are from firearms such as wheel-locks or flintlocks repurposed to initiate a larger explosive charge.

However I have continued to encounter these mechanisms at every turn of my research. The deeper I dive into historical documents the more I think they were much more common than I had realised. In fact I think they were a usual way of initiating IEDs for about 250 and even for as long as 330 years. I think that’s surprising and worthy of explanation   The wheel-lock and its successors, the snap lock, the snap-haunce and the flintlock are essentially spring loaded levers operating around an axis which contrives to place a spark ignition system in direct proximity to gunpowder. In a firearm the “trigger” is pulled by the person aiming the firearm - the pull of the trigger releases the spring-loaded mechanism. In general terms in an IED the trigger is pulled or released by another mechanism such as a lever or a cord. But it is the same mechanism.

The developments of gun locks for firearms were paralleled and linked inextricably with the development of household locks for doors and chests, and the same people made both.  There is also a distinct parallel in technological development terms with clock making which saw some significant developments in about 1580 with the development of spring driven rather than pendulum driven mechanisms, and one sees this being a mechanism that enables mechanical timing mechanisms in IEDs for the first time at around this date.  But the clock is only a component to release a spring loaded lever, allowing the flint, for example, to strike and cause sparks.   One can still see the influence of clock making in fairly modern fuzes, and I think that’s an area for future research, to explore the early parallels of lock mechanics with fuze mechanics. Indeed the language of clocks and explosive fuzes is very similar in describing components - ”fuzes" and “trains".

I’ve discussed before some of this , in relation to the invention of detonating systems,  but here I want to concentrate on the locks and the derived implications to IED design. 

Here’s an outline of the technology:

Prior to 1500 firearms were fired with "match locks". Pulling a trigger caused a slow burning cord, (a "match")  held on an "s" shaped lever to be pushed into contact with the gunpowder charge. In about 1500 the wheel lock was developed as a sophisticated mechanism to initiate a firearm without a pre-lit match.  The wheel lock is a spring loaded steel wheel which acts with friction against a piece fo pyrite to produce sparks, pushed against it by a spring loaded lever or "dog".   The resultant sparks land upon the beginning of the gunpowder train. (think of a Bic cigarette lighter, yet the thumb which turns the steel is replaced by a spring).  A simple "detent” safety catch is easy to include which prevents the spring loaded mechanism being moved until the device is set up in place.  Thus the wheel lock is:

  1. Safer than using a matchlock where a slow burning fuse ("match”) is introduced to the gunpowder train (not a good idea with a large charge of gunpowder immediately adjacent)
  2. Able to be left in place for as long as the gunpowder doesn't deteriorate
  3. Able to facilitate its containment and concealment (partly due to its small size) within an enclosure, which again a matchlock is not suited to.
  4. Able to prevent the give-away smell of  a burning match and the sight of a glow.

So in IED terms the wheel lock and its sucessors enable ease of use, concelament and safety, all key asopects for someone wanting to use an IED.

Pyrite is used in wheel-locks rather than flint because flint is too hard and the wheel would wear away rapidly. The wheel-lock is quite a complex piece of engineering and therefore expensive, which would have been a discouragement for the “one time use” within an explosive device.  

The snap lock was introduced in the late 1540s. The key to its design is that it is simpler, with less moving parts - simply a spring loaded lever holding a flint that falls on a steel or “frizzen". There is no wheel to wear out, and much less complexity, meaning that it is cheaper and therefore more likely to be “thrown away” in an IED.

The snaphaunce LINK developed in the 1550s and the flintlock LINK developed in 1620, were basically improvements on the snaplock design , allowing the pan to be covered for safety and to keep out the weather - the essential difference between these latter two is the mechanism by which the pan of gunpowder was uncovered.

So, between 1500 there is a period of 120 years of technological development to get from the original matchlock to the safe, flexible, cheap, easy to operate flintlock. Here's a video showing in a bit more detail how a flintlock on a firearm works.

From about the 1540s it may have become an economic option to use a gun lock in a “one time use” IED - perhaps from a broken firearm.

The next issue to address is how the trigger is pulled or released to allow the gun lock to fire.  There are essentially three principle modes of initiation for IEDs, all based around the fundamental idea that the perpertrator does not want to be near when the device explodes -  and the firing lock can enable each one of these three:

  • By command from a distance.  Simply by tying a cord to the trigger of a gun lock a device can be initiated from a safe distance.
  • By a victim’s action.  By tying a cord to the trigger and attaching the end of the cord to an attractive object or some other thing likely to be moved, the perpetrator can cause the initiation by a victim.
  • By timer. if the firing lock trigger is attached in some appropriate way to a clockwork mechanism, then after a set time, the trigger will be pulled.   

The following examples detail use of these three technique from the period between 1585 to 1918 - a significant period of history

In the 1570s the somewhat exotic inventor Ralph Rabbards describes contrivances that require some sort of spring loaded mechanisms to initiate explosives, and at the same time Samuel Zimmerman of Augsberg described explosive devices set off with hidden springs and string.    Zimmermann discusses “booby trapping” a chair that will initiate a device when sat on, and booby trapping a “purse of gold” left lying in the street.    I’m pretty certain that these devices would have used a gun lock initiator - how else would they have been initiated?  The technology was there and there are no other apparent mechanisms available to the bomb designer of the time. 

In 1581, the Polish besiegers of the City of Pskov sent a jewelled casket to the occupants of the city of Pskov. The device exploded when it was opened by the Russian defenders.   This booby trap mechanisms must have been initiated by a gun lock , adapted and contained in the casket.

This link here, tentatively dated to the 1580s shows 4 command initiated devices, initiated by operators pulling a cord from a distance. One has to assume that the cord was attached to the trigger of a firing lock buried in the barrels on the route of the target convoys. Not much changes does it?

In 1585, Giambelli’s clockwork Hellburner was triggered by a clock provided by Antwerp clock maker Jean Bovy.  Now techncialy, that could have been a lever, activated by the clock, which moved a burning match.  But I think a gun lock is more likely.

In 1628 Cornelius Drebbell (the inventor of an early submarine) developed floating devices used (unsuccessfully) by the English Navy against the French in La Rochelle. I have found this description of Drebbels explosive devices, written by Carles Bernard in 1628 in the Mercure Francois:

`During the night between Sunday (Oct. 1st.) and Monday, the English shot ten or twelve floating petards for the purpose of setting fire to the royal French fleet. The body of these petards is of white iron filled with gun-powder and floats on a piece willow wood, through which a spring is made, which when it encountered the bows of one of the royal ships, took effect, which consisted simply in this, that it threw water into the ship with much power; all the others were captured as they floated on the water and did no harm.’

So, my assessment is this - the iron cased charge is mounted on the floating wood platform, some form of spring powered lever acts on the device when it comes into contact with the enemy ships.  I think the most likely technology of the time which could have utilised that spring action is to release the trigger of a gun lock. I’m happy to consider other solutions but to me I’m now fairly certain.  One historian has suggested that Drebbell, who was known to have dabbled in alchemy, may have used the first ever high explosive, the primary explosive Gold Fulminate (discovered in 1602) – but I remain unconvinced. Occams Razor suggests to me a gun lock.

This diagram below from about 1630, shows a clear representation of a booby trap with a basket of attractive objects , within which is a firing lock tied to one of the top objects - lift the attractive object, pull the cord and the firing lock will cause the device to explode. Look carefully and you'll see the lock at the bottom.

In 1645 we have this description of two IEDs, each clearly using a firearm lock attached to clocks.

In 1650 we have this device, using a pistol firearm lock, initiated by the pull of a string. 

In 1764 we have a postal device that utilised a booby trap using a firearm lock. 

In 1776 and 1777 The American revolutionaries used systems that instinct suggests to me were similar to Drebbel’s devices of 1628, but develped by David Bushnell. Buchnell also followed Drebbels lead in submarine vessel ideas.

Here's part of the timing mechanism that Bushnells famous "Turtle" submarine was meant to fasten to the bottom of HMS Eagle. The timing mechanism's gears ultimately tripped a flintlock mechanism to fire a gunpwder charge. (Photo John Wideman)

Bushnell also used floating explosive charges with levers on the outside designed to be pulled when they came into contact with ships, very much like Drebbels devices of 1628. 

This image is a replica of a Bushnell IED that was floated down a river towards the Britsh ships. The lever on the outside causes a flintlock on the inside lid of the barel to be activated when the external lever comes into contact with the side of a ship, or a cable is pulled in some manner.

This image below is of an original revolutionary IED, the inside of the lid of the barrel, showing the flint lock mechanism held in place, to be activated by the lever on the outside. The flinlock shown appears to be from a British made "Brown Bess".

 (My thanks to John Wideman for allowing me to reproduce these images from his book “Civil War Torpedoes” where these pictures provide context for his very detailed and excellent work of later devices.)  

In 1805 Robert Fulton, an American working for the British Navy, (after being rejected by the French) designed a range of explosive devices using gun lock initiators. This diagram, produced by French technical investigators who captured and defused at least one of the devices following an attack on St Malo, shows clearly the firing lock mechanism adapted by Fulton as the explosive initiator. This diagram is one of my best finds.  This is a very sophisticated device and a very sophisticated techncial exploitation of the device by the French. The red annotations are mine, part of a lecture I give on historical technical exploitation.

In 1812, during the war with the British, Robert Fulton (who switched sides again, back to his mother country) used gun locks in a number of attacks using explosive devices on the British.  This attack on HMS Ramillies which was blockading American ports, used a very simple device, and nbot one of Fulton's designs, but nonetheless used firing lock.  It is described by Benjamin Lossing (thanks again to John Wideman for finding this)

In the hold of the schooner Eagle, John Scudder, junior, the originator of the plot placed ten kegs of gunpowder , with a quantity of sulphur mixed with it, in a strong cask, and surrounded it with huge stones and other missiles, which in the event of an explosion might inflict great injury.  At the head of the casks, on the inside, were fixed two gun locks with cords fastened to their triggers at one end and two barrels of flour at the other end, s that when the flour should be removed the locks would be sprung, the powder ignited and the terrible mine exploded. Thus prepared, with a cargo of flour and naval stores over the concealed mine, the Eagle sailed … . she was captured as expected and desired by armed men sent out on boats from the Ramillies.  The crew of the Eagle escaped to the shore at Millstone Point, and anxiously awaited the result. The wind had fallen and for two hours unavailing efforts were made to get the Eagle alongside the Ramillies for the purposes of transferring the cargo to that vessel. Finally boats were sent out as lighters, the hatches of the Eagle were opened and when the first barrel of flour was removed the explosion took place.  A column of fire shot up into the air a full nine hundred feet  and a shower of pitch and tar fell upon the deck of the Ramillies . The schooner, and the first Lieutenant and ten men from the flag-ship on board of her , were blown into atoms and most of those in the boats outside were seriously and some fatally wounded.

Although not involving flintlocks I have details of Fenian IEDs using high explosive initiated by pistols connected to timers in the 1870s, and Lawrence of Arabia’s railway IEDs in WW1 were initiated by adapted martini rifles firing mechanisms - which themselves were an idea copied from the Boers in South Africa in the Boer war.  However all these latter devices were in one sense different – they each actually fired a bullet into high explosive rather than igniting low explosive gunpowder.

I am by no means saying that every IED between 1540 and WW1 used gun locks - but gun locks enabled a simple and reliable way of initiating explosive charges and were used frequently and quite widely during the period.  A gunlock could be used easily to initiate a device, by those three key ways - by command, by the victim or by timer. A gunlock enables concelament and surprise.  I think these facts are crucial to an understanding of how IEDs were used in history.


An American terrorist in England

A friend of mine asked me my opinion on the most significant terrorist attacks in history. Here’s one which had pretty significant implications.

“John the Painter ” aka James or John Aitken, aka Jack the Painter, aka John Hill aka James Hinde was born a Scotsman but adopted America as his cause.  A petty, and not so petty, criminal he made his living as a painter and clearly his daily dealing with turpentine and flammable liquids prompted a thought.  He was also seized with enthusiasm for the cause of Independence for America, having arrived there in 1775. He became a prototype lone wolf terrorist.

In 1776 he knocked on the door of the leading American diplomat in Paris, France, Mr Silas Deane, and with a little encouragement described a plot to set on fire the key naval dockyards in England, thus crippling the British Royal Navy. He showed Deane his incendiary device:

Producing a portable infernal machine of his own invention, he explained his scheme. The machine consisted of a wooden box to hold combustibles, with a hole in the top for a candle, a tin canister, no larger than a half-pound tea can and perforated for air, to cover it; the whole to be filled with inflammable materials—hemp, tar, oil and matches. The candle, having been lighted, would burn down until it ignited the inflammable materials, and these exploding would scatter the fire for yards around.  

Deane gave him a little encouragement and a little money and sent him on his way.  On returning to England, John the Painter successfully burnt down the Rope House at Portsmouth Naval dockyard. He also set a number of fires in Bristol.  This created the public impression that gangs of American revolutionaries were active in the country. The King himself offered a reward for his capture and demanded daily briefings.

In an early form of Weapons Intelligence Investigation a failed device of the same design was discovered in an adjacent building to the burnt down rope house and subsequently witnesses attested that John the Painter had had it made in Canterbury.   John the Painter was hunted, arrested and tried – the transcript of his trial is available on line in Cobbett’s State Trials.  The device is described very clearly on a number of occasions by witnesses. An intriguingly thorough trial even down to the calling of a witness from whom he had bought matches.

He was duly transported to Portsmouth where he was strangled at the gates to the Naval Dockyard then hoisted up the 64 foot mizzenmast of the HMS Arethusa [specially unbolted and placed on land for the occasion]  then they eviscerated his body, tarred it, hauled it back up the mast and left him to waft in the wind for years as a warning to all and sundry.

The mast was the highest gallows in England’s history. 20,000 people attended the execution (quite a number, given the population of Portsmouth was 13,000)

So, why was this so significant in its implications? Here’s why:


  1. The fires in Portsmouth and Bristol caused terror across England. Vigilante groups patrolled the streets of ports.  Thus the arson attacks really did terrorize the nation.
  2. The attacks turned the public opinion – there had been significant support for the American revolution, especially in Bristol, but this public support was turned on its head. Had this not occurred, and more negotiated independence may have been achieved. Who knows what that may have looked like?
  3. The public mood allowed the production of the 1777 Treason Act and for years after the death sentence for murder in the UK had been abolished in 1965, the death sentence was still permitted for treason, and explicitly included in the list of treasonous acts was arson in the naval dockyards.


 A newspaper of the time stated:

"Of all bad characters, an incendiary is the foulest. He acts as an assassin armed with the most dreadful of mischiefs, and in executing his diabolical purposes, involves the innocent and the guilty in the same ruin."