Timed IED, 1864, City Point Virginia

Here’s a good report by an undercover Confederate operator, John Maxwell, in the American Civil War, describing an operation in August 1864 where he was able to deliver a “horological torpedo”  (a timed IED in modern parlance) to a Union munitions barge named the “J E Kendrick” in City Point, Virginia.

The IED detonated and caused a large quantity of munitions aboard the barge, and neighboring ships and barges to explode, killing at least 43 people.  The device had a clockwork timer and 12 pounds of explosive, but with the munitions also detonating it would have been several tons of explosive that went up.  Some reports suggest that Maxwell himself designed and built the device. he watched the explosion from about 3/4 of a mile away.

Sir: I have the honor to report that in obedience to your order, and with the means and equipment furnished me by you, I left this city on the 26th of July last, for the line of the James River, to operate with the Horological Torpedo against the enemy’s vessels navigating that river. I had with me Mr. R. K. Dillard, who was well acquainted with the localities, and whose service I engaged for the expedition. On arriving in Isle of Wright County, on the 2nd of August, we learned of immense supplies of stores being landed at City Point, and for the purpose, by stratagem, of introducing our machine upon the vessels there discharging stores, started for that point. We reached there before daybreak on the 9th of August last, with a small amount of provisions, having traveled mostly by night and crawled upon our knees to pass the East picket line. Requesting my companion to remain behind about half a mile, I approached cautiously the wharf with my machine and powder covered by a small box. Finding the captain had come ashore from a barge then at the wharf, I seized the occasion to hurry forward with my box. Being halted by one of the wharf sentinels I succeeded in passing him by representing that captain had ordered me to convey the box on board. Hailing a man from the barge I put the machine in motion and gave it in his charge. He carried it aboard. The magazine contained about twelve pounds of powder. Rejoining my companion, we retired to a safe distance to witness the effect of our effort. In about an hour the explosion occurred. Its effect was communicated to another barge beyond the one operated upon and also to a large wharf building containing their stores (enemy’s), which was totally destroyed. The scene was terrific, and the effect deafened my companion to an extent from which he has not recovered. My own person was severely shocked, but I am thankful to Providence that we have both escaped without lasting injury. We obtained and refer you to the enclosed slips from the enemy’s newspapers, which afford their testimony of the terrible effects of this blow. The enemy estimates the loss of life at 58 killed and 126 wounded, but we have reason to believe it greatly exceeded that. The pecuniary damage we heard estimated at $4,000,000 but, of course, we can give you no account of the extent of it exactly.

 There is an interesting description here of the effects of the explosion.

Initially the explosion was attributed to an accident, but Maxwell’s report came out some time later.  I have also found a good diagram of the device, and in particular of the initiation system which I have annotated.

Timed IED containing 12 pounds of explosive in a box with a clockwork timing initiator

The timer works like this:

1. A piece of wire holds the the balance wheel of the clockwork mechanism. the wire protrudes from a hole in the wooden box.  At the appropriate time the wire is withdrawn, feesing the clock and “arming” the device.

2. As the clock mechanism operates the clockwheel is rotated.

3. Eventually the lever, which has a stud protruding at its rear, falls into the slot.

4. The action of the lever falling into the slot releases hold of the hammer.

5. The hammer is forced by a spring to act against the percussion cap.

6. The percussion cap initiates the main charge.

Matchlocks, Samurai, Money and a Pretty Girl

Here’s another interesting tangent I came across while investigating some historical stuff.   I’m interested in how technology enables new weapon designs, and the principle of “stealing” munition technology in history has occurred many times.

I came across this story of how the Japanese obtained firearms from a Portuguese vessel in 1543 and reverse engineered the weapon.  The Portuguese matchlock was very modern and innovative technology as far as the Japanese were concerned, almost akin to magic.

Readers will recall from earlier posts that in the mid 15th century matchlocks were used in Europe.  The Portuguese were exploring the Far East and they were using a spring assisted “snapping” matchlock.  In this the trigger mechanism releases the “cock” holding the burning match and a spring causes the match to rotate onto the powder pan.  Readers of James Clavell ‘s “Shogun” will know the story of Europeans arriving in Japan.  In September 1543 a Chinese junk, with Portuguese adventurers aboard, made anchor after being damaged in a storm at the island of Tanegashima off the Japanese coast.

The lord of the island, Tokitaka, purchased two of the matchlocks which were sold “for a great profit”  and tasked his sword maker with producing replicas – a very early example of foreign material acquisition and reverse engineering.  Japanese swordsmiths were expert metallurgists, but the swordsmith had difficulty in machining  the barrel so that the screw on the end could be fitted.  The screw can be seen in these images, and could be removed to allow the barrel to be easily cleaned.

 

 

A year later, a Portuguese blacksmith arrived in Japan ,and he was persuaded to pass the engineering secrets.  Legend suggests that the Portuguese blacksmith was offered the hand in marriage of a beautiful woman called “Wakasa”– a nice reward for switching sides and bringing key technology with you.  Within 10 years, 300,000 “tanegashima” matchlocks had been produced, completely revolutionizing  Japanese warfare.

Ingenious Japanese engineers then improved the basic design adding designs to protect the firing mechanism from rain, and experimenting with larger calibres. Here’s a great contemporary image of Japanese musketeers in rain gear with boxes fitted around the firing mechanism to keep the rain off.

Interestingly, the Japanese retained use of matchlocks, even when the rest of the world moved on to flintlocks in the 1600s, and in fact retained the use of matchlocks until percussion cap rifles were introduced in the mid 1800s (about the time of the film “The Last Samurai”)

Japanese matchlocks were all individually hand-made and generally parts were not interchangeable between weapons.  The Japanese weapons were not fired by holding them to the shoulder, the butt was placed next to the cheek and both arms held the weapon in front of the firer. This though was not unique to Japanese matchlocks and was also seen in many European weapons of the time.  There’s a good video here – note the delay between the powder in the pan firing and the powder in the barrel firing

I’ve found a translationof how Japanese blacksmiths made the barrels of the weapons – and you can see the great metallurgical expertise of Japanese swordmakers being applied to this engineering process

1. To make a Teppo, one first makes an iron bar called a “shingane”. For a Teppo one shaku (30.3 cm) in length, the shingane would be one shaku longer, or four shaku. Straw is wrapped lightly around one of the ends of the shingane in order to make it easier to pull out during the teppo-making process.

 2. Next, an iron sheet, called a “kawaragane” is prepared in the appropriate size and thickness to match the teppo. When the kawaragane is ready, it is wrapped around the shingane; the shingane is taken out when the teppo is put on the fire and put back in when the iron is being forged. After the iron has been well forged, the seam is heated until it acquires a paste-like texture and welded together. This is called “wakashizuke”. This condition, consisting of a rolled kawaragane, is called an “ara-maki”. From this stage, polishing the barrel with a file and attaching the necessary parts will result in a finished teppo. This type of teppo is called a “udon-bari” and is an inexpensive standardized product.

 3. Expensive and well-made teppo are made by joining to the aramaki barrel many sheets of iron, hammered into long strips, wrapping them around the barrel and forging them by wakashi-zuke to make a stronger teppo. The result is called “kazura-maki”.

4. More “kazura” (iron strips; literally, vines) are welded to make a half-molten ara-maki. This is fully melted and welded together, using a hammer to forge the iron from the edge. This is called “tsume-maki”. Sometimes, at this point, the cartridge chamber is doubly wrapped. At this stage, the muzzle is wrapped thinly and the breech thickly in a kazura-maki, resulting in an almost complete barrel.

 5. If the entire barrel, and not only the cartridge chamber, is to be doubly wrapped, the strips are wrapped in the opposite direction as the first time. The result is a doubly wrapped barrel.

6. Next, a thick iron sheet is wrapped around the thinner end (the muzzle) to make the “koji”. A rough mold of a pan is made and placed in the cartridge chamber.

7. The resulting barrel is called an “arakata-zutsu”. The arakata-zutsu is put through a hole in a “katagi” (hardwood) and fastened with wedges and the bore is polished using a steel drill. First a rough drill and then, in the final steps, a finer drill is used.

8. Next, an auger is used to cut a breech bolt hole on the breech.

9. After one is finished with the auger, a file is used to shape the upper half of the teppo into a round shape, for a round barrel and an octagonal shape for an angular barrel. The shape of the pan is adjusted and the foresight and rear sight are welded on to the teppo by wakashizuke and fastened with breech bolts. Furthermore, a platform for a rivet to be secured to the gunstock is attached to the bottom of the barrel.

10. Now the teppo is finished. The foresight and rear sights area adjusted next by placing a target on the same level as the bore, normally at a distance of 6 ken (10.9m), and crisscrossing some string in front and behind the barrel, and aiming at the dark spot on the target through the bore. The barrel is then secured; this time one aims at the dark spot on the target through both sights to adjust the sights. This is called the “deai sadame”.

11. After this step, a plank equipped with a mechanism is fitted onto a gun rest made of old hardwood and match clippers and, in the case of an outside mechanism, a spring, as well as a rain-guard, smoke-guard, and trigger are attached to complete the teppo.

I found the above here where there is also a first person description of the arrival of the technology, allegedly written in 1606. Worth a read.

Some of my best friends are Sappers… (Sappers, Doctors, explosives and smoking dope)

My last post about the evolution of detonators involved digging around in some interesting history. I came across two fascinating reports about a British military engineering operation on the Hoogly River in Bengal in 1839 and 1840. The crucial piece about this story is that it straddled the invention of sub-aqua electrical initiation of gunpowder charges as used by Pasley with the earlier much less reliable igniferous technique, in this case using tubes of lead filled with gunpowder, soldered together.  The reports are found in the professional papers of the Royal Engineers, 1840 and Volume 8 of the Journal of the Asiatic society of Bengal, 1840. Go google if you want to read the originals.

The circumstances were that a ship, the Equitable, had sunk on a sandbank and was posing a hazard to shipping. So a young British military engineer, Captain Fitzgerald serving in the Bengal Engineers and some colleagues decided to blow it up, as is the wont of young Engineer officers.  In this case (and not for the last time), they were accompanied, encouraged and assisted by a young medical officer

So, this was a complex operation in a fast flowing and murky river. The Equitable had sunk in October 1839 in the middle of the shipping channel.  It was decided to use large gunpowder charges to break up the vessel.

Attempt 1, Igniferous – Failed.

The first attempt used a large waterproof cylinder full of gunpowder, ignited by means of a linen hose protected by lead piping.  The charge was an enormous 2400 pounds of powder.  The cylinder was an oak cask, bound with iron hoops, and plates of lead were carefully soldered onto it to seal it. The lead pipe protecting the powder train in the hose was made from four 15 feet lengths, soldered carefully together. The hose, one inch in diameter and containing gunpowder was then inserted into the pipe.  I have a description of the explosive chain between the main charge and the gunpowder hose, but have not yet found an associated diagram. so I can’t yet make head or tail of it.  The characteristics of a loose filled gunpowder hose clearly gave rise to challenges, in terms of transmission of the igniferous process in a vertical pipe. To manage this the hose was knotted every 6 inches, and held in place by fastening to a pewter wire inserted down the length of the pipe.

The seal between the powder hose in the pipe and the “primer cylinder” appears to have been achieved with brass fittings and leather gaskets.

The first attempt took place on December 6 1839, and the charge was lowered from a boat onto the deck of the sunken ship.  A “portfire” with an estimated burning time of 10 minutes fastened to the top of the gunpowder filled pipe, and the boat rowed away.  However the portfire failed to ignite the gunpowder train. A second portfire was set, and after a few minutes a muffled small explosion was heard, which was assessed as being the pipe rupturing. The main charge failed to ignite, and the pewter wire was ejected from the lead pipe. The pipe was raised and the rupture found at 25 feet from the top.

Attempt 2. Timed, electrical, using a watch – Successful

For the second attempt the Egineer team, encouraged by a medical doctor William O’Shaugnessy, and no doubt hearing of the success of Pasley, used an electrical initiation method.  O’Shaugnessy “read up” on electrical theory and designed and built his own galvanic battery, a description of which can be found in the reference. O’Shaugnessy conducted several experiments with his battery and platinum wire or platinum foil filaments, making the foil white heat with its electrcial resistance.  Working the physics, O’Shaughnessy established that with some careful design he could initiate the platinum filaments through bare un-insulated wire, under water, provided he kept the “legs” sufficiently far apart and the battery powerful enough.  He also designed a highly ingenious system for holding the filament in a sealed container using a breech of a gun.  Furthermore O’Shaugnessy then designed a remarkable timing initiation using a simple watch, copper “arms” and mercury filled tubes that the copper arms of the watch swept through that automatically “made safe” the firing circuit four minutes after initiation, so it would be safe to recover if the initiation failed.  It is clear from O’Shaugnessy’s report that he had no actual reports of Pasley’s successes other than newspaper reports, and so was working on first principles.

The second attempt took place on 14 December 1839, using this electrical mechanism, the battery and timer being in a small fishing boat above the charge. After setting charge, the demolition party consisting of Capts Fitzgerald and Debude, and Lieutenant Smith, accompanied by O’Shaughnessy and his assistant Mr Siddons, rowed quickly away.  Here’s O’Shaugnessy’s description of the subsequent explosion:

At the thirteenth minute a slight concussion was was felt in our boat, a sound like that of a very distant and heavy gun at sea was heard, and a huge hemispherical mass of discoloured water was thrown to the height of about 30 feet. From the centre of this mass there then rose slowly a and majestically a pillar of water, intermingled with foam and fragments of wreck , and preserving a cylindrical form till it reached an elevation of at least 150 feet. The column then subsided slowly, a wreath of foam and sparking jets of water following its descent, and rendering the spectacle one of indescribable beauty.

O’Shaughnessy later also significantly improved the manner in which the heated platinum filament ignites the charge. Previously the heated filament was embedded directly into gunpowder but O’Shaughnessy found that by embedding the filament in cotton which had been soaked in a solution of “purest saltpeter” effectively lowered the temperature that the filament was required to reach to cause ignition.

Attempt 3, Electrical using an improvised timing mechanism involving portfires and “string” – Failed

A third operation occurred a month later to remove a large part of the sunken wreck still remaining, and this too used a timing mechanism and electrical initiation, however the system failed to initiate due to damage to the priming charge where it was fastened to the main charge.  The sapper officers revised the mechanical timing mechanism of an adapted watch used by O’Shaughnessy and used portfires burning string at timed intervals to make and then break a circuit if detonation had not occurred – I see in the different reports of Capt Fitzgerald and Dr O’Shaughnessy a little irritation from the good doctor as to the contrived nature of this measure, which he regards as crude an unreliable, but which the sapper officers are very proud of (it saved the expense of a watch).

Attempt 4. Electrical using an improvised timing mechanism involving portfires and “string” – Successful

A fourth operation took place on 28th January 1840.  A successful explosion took place, breaking up the remaining part of the wreck and also killing two porpoises.

O’Shaughnessy went on to an interesting career where he was involved in pharmacology, the electric telegraph, encryption and most famously the introduction of cannabis to the UK for “therapeutic use”.

Inventing Detonators

I’m intrigued by the chain of historical inventions that led to the modern detonator.

Detonators for explosive charges evolved from firearm trigger mechanisms and I see these as an invention continuum, with one leading to another. Alongside these mechanical inventions, chemical discovery runs as a parallel track, particularly the discovery or primary explosives and high explosives, which detonate by shock (gunpowder being a low explosive which explodes by deflagration)

Initially, I guess the first “initiators” were simply burning fuzes which transmitted a flame to gunpowder. However there is some early mention of a some victim operated mechanisms perhaps using friction devices or steel and flint levers.   See Chinese IEDs here.  

To help undertsand the chain of scientific, chemical, physical and mechanical inventions that took us down this path the folloing rough time line might be useful:

Pre 1400 – Burning fuzes of various types, igniting gunpowder by burning.

Early to mid Mid 1400s – Invention of the matchlock mechanism to initiate firearms. Note that this was definitely a European invention – the Portuguese took matchlocks and introduced them to China and Japan.  (The story of how the Japanese obtained and reverse engineered the matchlock will be the subject of a future post) .

About 1500 – Invention of the wheel-lock, possibly by Leonardo Da Vinci, which introduces a new mechanical action to apply a burning fuze to a specific point.

1540 – The snaplock was invented, using a flint initiator. This was a precursor to the more sophisticated flintlock

1558 – The snaphaunce was developed which incorporated a mechanism for keeping the gunpowder covered until the flint fell, when the cover is opened automatically.  The cover is called the frizzen.

1588, a time initiated system used by Giambelli to explode the “Hoop”, with a timing mechanism causing ((I’m guessing with a snaplock or snaphance) to initiate the charge.

1602  Gold fulminate (the first primary/high explosive) discovered by John Tholde of Hesse.

1610 – The first flintlock initiation system developed The flintlock mechanism is an evolution of the snaphaunce whereby the frizzen is not only a cover for the pan of gunpowder, but also the steel face on which the flint strikes to cause sparks.

1659 Robert Hooke and Thomas Willis discover the primary explosive characteristic of Gold hydrazide

1745  Dr Watson of the Royal Society showed that an electrical spark from a Leyden jar could initiate a small blackpowder charge.

1750  Benjamin Franklin initiates gunpowder with an electrical spark and makes small paper tubes of  powder with two wires inserted and a spark gap created.

1788  Silver fulminate was first made by French chemist Berthollet.

1776 – American revolutionaries used adapted firearm mechanism to make contact mines consisting of “kegs” of gunpowder which were floated down rivers.  The kegs have fastened to the lid a wooden arm which when it touched a target ship connected to an iron pin, engaging a flintlock device from an adapted firearm, causing the main charge to explode.  Note the similarities in principle to much later IED initiators here.  I’ll post some images of these “kegs’ in future posts.

1777 – Italian scientist Alesandro Volta, describes how he had fired pistols, muskets and a ”mine subacquee” (underwater mine) electrically – it appears he used a hot wire to initiate a glass bulb full of a flammable gas.

1782 – Another Italian scientist, Cavallo, described detonation of a charge of gunpowder, electrically, using an incandescent wire embedded in the powder

1795 – Cavallo uses another method, using gunpowder mixed with steel filings, with two electrical probes embedded in it.

1799 – Fulminate of mercury, a primary explosive later used in detonators was first prepared by Charles Howard. Interesting reports on his experiments are here and I think its very significant indeed that Howard actually tested electrical initiation of mercury fulminate. I note also that Howard refers to French scientists electrically initiating some form of potassium chloride based explosive in the late 1700s.  Howard’s description of the experiments he conducted with mercury fulminate are fascinating – clearly he hoped he had invented an alternative to gunpowder, but initiating mercury fulminate within a gun caused some catastrophic damage to his equipment!  There is a great description of how Howard measured the volume of gas produced from a specific quantity of the explosive.

1812 – The Russian military scientist Pavel Schilling developed an electrically initiated IED, as a mine.  My apologies, in earlier posts I credited this to others later in the 19th Century, and I have only recently discovered Schilling’s  (and Volta’s, and Howard’s) technologies.  Schilling gradually improved the associated technologies, insulating wire with tarred hemp and copper tubing, and devising a carbon arc initiator.

Also in 1812 – Prussian scientist Sommerring improved the insulation of electrical wire, using rubber and varnish, allowing further capabilities to be developed in initiating explosives.

1820 – American scientist Robert Hare, worked on electrical initiation of flammable gases. Hare also developed a “plunger” type galvanic machine for producing electrical charges for this purpose.

1822 – Hare used  a hotwire embedded in a pyrotechnic mixture to initiate a blackpowder charge.  In the 1830s Hare also produced a tin tube container packed with powder and with an ignition wire for rock blasting but foresaw the military importance of command initiated explosive charges.

1829 – A young Samuel Colt initiated an under water charge electrically perhaps using a tarred copper wire.

1831 – The Bickford burning fuze was invented, taking away the guess work about time delays for burning fuses.

1837  Colonel (later General) Pasley of the Royal Engineers developed chemical then an electrical initiation mechanism to explode gunpowder charges under water. Pasley’s work appears to have been prompted by reading a  newspaper report of an “ordnance accident”, in Russia, when Tsar Nicholas I narrowly escaped death when viewing a demonstration of electrically initiated gunpowder charges used to blow up a bridge, presumably developed by Schilling. Pasley read the article and then sought the advice of English scientist Charles Wheatstone to consider how he might use the same concept.  Pasley’s contributions to military engineering are huge, and his explosive related inventions are very significant if only a part of that broader work.  I have yet to find details of Pasley’s chemical fuzes, but his electrical initiation mechanisms used electrically heated platinum wire, with the electricity provided by early galvanic cells. Pasley solved the problem of insulating the wires so they could be used under water, by coating wire with gutta percha. The platinum wire (or foil) provided enough heat to initiate the gunpowder it was embedded in.  However some reports state that the electrical system caused a detonation by a “galvanic spark” so the actual mechanism is still a little unclear.   I’m very intrigued by the chemical fuzes and how they worked, given the nature of the underwater tasks that Pasley developed the explosives for. I think it likely that there would have been some form of command pull to initiate the chemical reaction once the divers were clear and safe.  Chemically the reaction may have been similar to Nobel’s (later? ) designs.

1830s  –  Immanuel Nobel developed chemical initiation mechanisms to initiate gunpowder. The mechanisms used a glass vial containing suplhuric acid, which when broken (usually by an enemy) caused the acid to fall by gravity onto potassium chlorate, which ignited and caused surrounding gunpowder to initiate. These were confusingly called “Jacobi” fuzes after the Russian scientist for whom Nobel worked.  Jacobi led the Russian “armed services committee for underwater experiments” between 1839 and 1856. It is clear that Jacobi’s secrecy prevented international publication of the scientific achievements he made in electrical initiation. Jacobi’s work  from 1839 seems to have been prompted by both Schilling and Pasley.  What is significant is a reference I have found to Jacobi developing “mercury connecting devices” which probably mean some form of mercury electrical switch to initiate contact mines in the 1850s.

1830s, Mercury fulminate was used in copper caps used as firearm initiators taking the place of flint, and making the process of initiating a firearm much less dependent on flint and the weather.

1839 – Other British Royal Engineer salvage operations in Bermuda and in Bengal on the Hoogly river used electrically initiated charges.  I have a great piece of reseacrh to blog about with regard to the Hoogly river operation.

1840s – Samuel Colt conducted extensive work on highly complex electrical initiation systems for sea and river mines.

1848 – Werner von Siemens developed electrically initiated sea mines.

1863 – Alfred Nobel (Immanuel Nobel’s son) published his patent for a practical detonator to initiate nitro-glycerine.  Note that this was four years before his patent for dynamite.  In modern parlance this was a non electric blasting cap, itself initiated with burning fuse.   The detonator consisted of a small blackpowder charge, a wooden plug and a small quantity of nitroglycerine held within a metal cylinder. The black powder is initiated by a burning fuze, which pushes the wooden plug down the cylinder, which then strikes the niroglycerine with kinetic energy.

1865 –  Nobel refined his detonator design significantly, with a small metal tube containing mercury fulminate

1868. H. Julius Smith produces a detonator that uses a spark gap and mercury fulminate.

1875 The electrical detonator using a hot filament was developed independently by Gardiner and Smith

Combined EOD and munition repurposing!

Bizarre video here but appears to be true.

Further evidence of a remarkable improvised weapon industry in Syria.

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