My old friend Panjandrum saw a military history magazine in a newsagent’s today and took this image of Page 35.
Given the title of the article in the magazine, this blog’s title, and this piece from this blog in 2012, that’s a fine coincidence!
For what it is worth I’m pretty sure that Garland didn’t serve in the Boer War as the magazine articles suggests, but I have no doubt the concept of initiation system came from there.
I’m steadily working through a book that was published in Latin in 1650, “The Great Art of Artillery” by Kazimierz Siemienowicz. The book was translated into French, then from there into English in 1729 and of course that’s the version I’m studying. The breadth of subjects covered is remarkable, including physics, chemistry, mathematics, explosive processing, explosive storage and other related things. There’s a lot about artillery and some interesting rocket technology related to my earlier post about the English rocket experimenter Robert Anderson who was making his rockets in 1696. I have an interesting blog post “cooking” on the technical similarities of rocket design from these two engineers, working in different countries 46 years apart. And readers of this blog will recall that the revolutionaries in Dublin in 1803 used Anderson’s rocket manufacturing instructions and it is very possible that one of the revolutionary Irishmen went to Woolwich in subequent years to assist Congreve in the manufacture of his rockets. Give me a few weeks to bottom out that detail and assess the apparent links, but this 1650 document is pretty remarkable in its technical detail, with multi-stage rockets being explicitly manufactured.
As well as covering artillery and rocketry, amongst the book are also numerous references to improvised explosive devices. For example there’s reference to a large barrel or cylinder shaped IED used in the Seige of St Andrews in 1546 that killed 321 and injured hundreds of beseigers. Ths large barrel containing “powder, stones and Iron bolts” was rolled down amongst the enemy. I’m trying to find a cross or supporting reference for that, as that’s pretty early in my historical time line of IEDs. Siemienowiz quotes his reference to the St Andrews device as being written by an Italian in a book called “Precepts in the Modern Art of War” that must have been published prior to 1650. Unfortunately the name of the Italian author is not clear and varies between translations and I have yet to unearth it.
Here’s another example from Siemienowicz referring to command initiated improvised devices using the flintlock mechanism I have described in some recent posts – remember this was written in about 1650. This text below is from a 1729 translation:
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.
Roger DaviesAs a follow up I found this excellent image from a French military handbook published in 1616, showing how a small one handed wheel-lock pistol could be used by a “new” cavalryman against a “traditional” knight in armour with a lance. Step one, shoot the knight from beyond the range of his weapon, or alternatively, step 2, shoot his horse. Note the difference in armour of both protagonist.
This post is a bit of a puzzle, that I may need some help with. I’ve blogged before about the German sabotage campaign on the east Coast of America in 1915 here:
http://www.standingwellback.com/home/2013/9/17/kurt-jahnke-the-legendary-german-saboteur.html
http://www.standingwellback.com/home/2012/1/22/massive-explosion-in-new-jersey.html
http://www.standingwellback.com/home/2013/2/12/booby-trap-ieds-on-the-battlefield-1918.html
And indeed I’ve built up a bit of a presentation on German sabotage in 1915-1917 which I may get round to posting here. In brief summary, German agents either operating out of the German Embassy or operating undercover developed a systematic and effective sabotage campaign to disrupt munitions and other cargoes being shipped to the European Allies of France, Russia and Great Britain, before the US entered the war. There is documentation that certainly 35 ships were firebombed, and an additional 39 suffered suspicious fires. Many sabotage events were downplayed or not reported so the number could be significantly higher. A number of munitions factories in the US attacked. Five US Navy warships suffered fire damage, and the USS Oklahoma and USS New York, two new battleships under construction were almost completely destroyed.
Most of the cargo ships sabotaged in 1915 were attacked with small incendiary devices, the size of a cigar. These contained sulphuric acid in one small compartments separated from picric acid or potassium chlorate, by a copper disc.. The copper disc was dissolved over time (usually several days) and then the sulphuric acid was in contact with the other compound causing a violent ignition. Typically a number of these “cigars” were secreted in the cargoes in a ships hold by stevedores of German or Irish extraction in US East Coast ports. Some devices were made aboard German ships, interned in US ports when the British blockaded them. One in particular, the “SS Friedrich der Grosse” of the NordDeutschland Lloyd line was docked in New York and German agents ferried the devices from the ship to the dock workers to hide on board munitions and cargo ships. Other cigars or “pills” as they saboteurs described them, were made in the laboratory of the designer, Dr Scheele at 1133 Clinton Street, Hoboken, New Jersey.
The “cigars” were to a design develped by a German sympathiser, Dr Scheele, and are reported to have been about 4 inches long. Once initiated they ejected white hot flames from both ends.
Now, there appears to have been more than one design. In a diagram produced by another saboteur, Frederick Hermann, the construction of the incendiary appears a little more complex, than simply two compartments in a lead pipe separated by a copper disc. It is hard to interpret the diagram below but I note that the compound to which the acid mixes is described as chlorate and sugar, which will make a difference to its explosive effect, depending on relative qunatities of the mixture. The diagram appears (I think) to show an upper reservoir of sulphuric acid, a “neck” halfway down labled “c” (for copper, presumably a copper plug and not a disc), and below that the chlorate with sugar. Wax probably closed both ends.
It should be noted that to work effectively the cigar needs to be positioned vertically, to allow the acid to dissolve the copper and then fall into the chlorate-sugar mix. Only a proportion of the devices functioned and some were recovered by French and British governments in ports in Europe. In 1915 this activity was being led by two officers from the German embassy , Karl Boy-Ed, and Kapitan Franz von Papen. Later in 1915 a secret agent of the German Navy Franz von Rinteln was sent to encouage the sabotage campaign. In a range of investigations led by the head of the NYPD bomb squad, Thomas Tunney, who was seconded to Military Intelligence, the German sabotage cells were largely disrupted. By 1917 the US had entered the war, Rinteln was captured and imprisoned in England and the others had been arrested, expelled or in the case of Dr Scheele, escaped to Havana.
Given that history it was intriguing to find a report on the Australian War Memorial blog about an incendiary device recovered from a ship in 1918, possibly in Liverpool, from a ship arriving from the US. By 1918 most of the German sabotage cells had been rounded up, also the design of the incendiary device is somewhat different.
These images are included on the AWM blog and I’m grateful for their kind permission to reproduce them here.
Working from the photographs alone, it appears that the knurled steel “head” appears to have two openings in it, closed by bolts. I would have perhaps expected only one, to simply fill with acid. The main body appears to be copper and the strange shaped base appears to be aluminium (?), corroded by a galvanic reaction. The base is an odd design. This device, bigger than the earlier cigars would have been more difficult to smuggle aboard and its dimensions would have made it more difficult to conceal in a cargo. The description accompanying the images suggest that rather than acid eating through a reservoir wall in this case the acid ate through a wire which retained a spring action to an initiator…. that’s a quite different initiation mechanism. This device would have taken more skill to construct and the threaded and knurled head, the apparent 3 sections of copper pipe and a neat fitting of the copper pipe to the aluminium base indicates a higher level of engineering…. Something about the base design rings a bell, but I can’t put my finger on it. The design of the base must have a reason and there must be a reason for it to have been different from the copper…but I cant work that out. Any suggestion gratefully received.
The blog from the AWM also has set me off on a new thread. The device appears to have been forwarded to the Australian section of the British “Munitions Inventions Department” in Esher, for examination. The Munitions Inventions Department had been set up earlier in the war to coordinate the wide range of scientific and military engineering developments required by the Allies to win the war. It was really the forerunner of later government defence research departments. Teams of ingenious, pragmatic and capable engineers had been co-opted into developing a wide range of innovative weaponry. By all accounts the Australians were masters of such craft and contributed significantly to a wide range of innovative munitions. I’ve started some research on that and will no doubt blog about some of the wilder and more interesting inventions in the future.
Roger DaviesSo a follow up on the mystery device. I have some thoughts beginning to crystallise.
1. I think the corroded base might be Magnesium and not Aluminium. Magnesium would also also be subject to galvanic corrosion (same principle as “sacrificial” corrosion) as it remains in contact with the copper cylinder.
2. In around 1917 German forces developed air dropped incendiaries that used magnesium, dropped by Zeppelins on England. These were impact fuzed, and contained a thermite charge. The thermite then reacted with a magnesium body to cause a fierce fire. Most UK EOD folk will be aware of a further development of these which were used extensively in WW2, and we, the Brits, called them 1kg incendiary bombs. The Germans called them either “Goldschmidt bombs” after the guy who discovered the Thermite reaction, or Elektronbrandebombe or Elektron incendiary bombs, “elektron” being the German name for the magnesium alloy of the body.
3. So.. I think it is possible that this device is a “home made” variant of a German Elektron incendiary. If that is the case then the impact fuse has necessarily been replaced with an acid time fuse, as required in the ship sabotage use-case. Thermite would have been contained in the copper piping, and the magnesium base provided to get the high energy heat, initiated by the thermite reaction. In some of the earlier Zeppelin bombs the body of the core of the bomb was wrapped with rope soaked in tar to give additional burning. This might explain the wide base at the bottom with the tar soaked rope wound around the central core, above the “shelf” provided by the base.
4. Here’s an image of an early incendiary dropped from a Zeppelin (this one is not an elektron bomb, I think).
And here’s one after it is burnt out showing a broad base on which the rope is mounted and a central core:
The design of the magnesium incendiaries evolved quite quickly – here’s what they looked like by the end of WW1 and pretty much through to WW2, with only minor changes:
So… my best guess at the moment is that the device on the AWM site is an improvised incendiary, that may have been wrapped in a tar soaked rope originally and may have contained a thermite charge inside the copper tubing. The base might be magnesium and in the intervening years has galvanically corroded. It will continue to corrode, slowly as it remains in contact with the copper tube. The initiator was a timed mechanism probably using acid to erode a wire, which released a spring allowing a striker to initiate a charge which then ignited the thermite. But I’m far from certain. This means that these later devices, in any event, were much larger than the small 4 inch cigars used in 1915 and therefore harder to smuggle aboard a ship and conceal in the cargo. I’m very open to alternative interpretations.
Roger DaviesI have a new update, thanks to the curator at the Australian War Memorial Museum. Following this blog post they tested the base. I had guessed the base might be magnesium, but they found the base material consisted of Copper, Zinc and Manganese. Minor amounts of Arsenic and trace amounts of Titanium, Chlorine and Potassium were also visible.
Back to the drawing board…. Does anyone have any suggestions?
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 time 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:
