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Model of Leonardo's tank

9 wacky medieval war machines

A model of Leonardo DaVinci's tank

Stop someone in the street and ask them to describe a medieval castle siege and they would likely mention a big battering ram being heaved against tall wooden gates, a spoon-shaped catapult flinging a big boulder at battlements, and the old favourite – boiling oil being poured on to the heads of hapless knights by laughing soldiers.

There was much more to medieval military technology, though. Skilled engineers concocted increasingly sophisticated devices for ambitious rulers and cautious cities; money and resources were put into builder bigger and better ‘siege engines’; and weird and wonderful weaponry was designed to intimidate as well as destroy enemies.

Here we look at 9 of the most unusual war machines from the Middle Ages.

1. Leonardo da Vinci’s tank

Over four hundred years before the first modern tank made its debut on the Western Front in the First World War, Italian genius Leonardo da Vinci (1452-1519) designed what is believed to be the first-ever armoured vehicle, in 1487. Made of wood with metal sheeting on the outside, its conical design was to enable it to move in all directions and fire outwards on all sides. It was to be operated by men inside working hand cranks, with another group inside firing cannons.

Da Vinci wrote in a letter to the ruler of Milan:

‘I can make armoured cars, safe and unassailable […] and behind these our infantry will be able to follow quite unharmed and without any opposition.’

Never built, it was thought to have been designed by the great inventor with a deliberate flaw built-in: it could not move. Some have speculated that this was because da Vinci was a pacificist, while others have suggested that this was to prevent others from stealing his design.

2. Leonardo da Vinci’s giant crossbow

The ballista was a familiar sight on medieval battlefields. It was a siege engine like a crossbow in form, firing bolts, darts, or other projectiles. Da Vinci’s giant crossbow resembled a ballista but on a much bigger scale than anything that had ever been conceived of before.

Known as Leonardo’s crossbow, it was intended either for defence or possibly for use in sieges.

Designed in the 1480s and collected in Da Vinci’s Codex Atlanticus, it was never constructed (except for a TV show in 2002).

It had six wheels and measured roughly 27 metres long and half as much across.

It was to be built of thin wood for flexibility and it had an innovative, aerodynamic design. It would also have been, if built, cost-effective, quiet (compared to a cannon), and hefty, with Leonardo expecting the weapon to fire projectiles weighing 45 kilograms.

It was a sophisticated machine with a gear for drawing back the bowstring and two alternate methods of firing, either by hammer blow or with a lever.

Conceived as a weapon to frighten the enemy, it was one of several designs presented by da Vinci to Ludovico Sforza (1452-1508), regent and later Duke of Milan, in the hope of being employed by Sforza as a military engineer.

Over 500 years later, experts are still in the dark about why the giant crossbow was never built.

3. Kyeser’s people blender

Konrad Kyeser (1366-c.1405) was a German engineer and author famous for his 1405 manual of military tech, Bellifortis.

In this famous textbook, Kyeser describes well-known devices such as battering rams and trebuchets, but also rockets, grenades, siege towers, mobile pontoon bridges, and battlefield troop carriers.

He also discusses astrology and the use of ‘magic’ in warfare.

One of the designs in Kyeser’s grisly guidebook was described by him as a ‘war cart’ which ‘shreds’ and ‘mangles’ enemy foot soldiers. The illustration for the cart shows six spears sticking out of each side, with a further five serrated barbs on each side, designed to spin with the motion of the cart and churn up enemy infantry.

4. The fire dragon – The ancient exocet

In the Huolongjing (Fire Dragon Manual’), a 14th-century Chinese military text, a host of fearsome weapons are described, including firearms, cannons, landmines, and ‘fire arrows’.

One of the weapons detailed in this book is the ‘huo long chu shui’, or ‘fire-dragon issuing from the water’. This was probably the world’s first multi-stage rocket.

This missile launcher had an opening resembling a dragon’s head and an opposite end with the appearance of a fishtail.

The first stage of the rocket launcher would ignite and launch the battery of exploding arrows out of the mouth of the dragon.

5. Leonardo’s submarine

Leonardo da Vinci’s ‘submarine’ invention was an empty shell with enough room for one person. It had a conning tower on top and was described by da Vinci not as a submarine precisely but as a ‘ship to sink another ship’. It was later discovered that da Vinci’s designs for this contraption would not have enabled it to fully submerge.

He conceived of many other devices for naval warfare, such as a one-man battleship, but because da Vinci was concerned about the deadly use his ‘submarine’ might be put to by ‘evil men’ he also designed more peaceful apparatus such as a machine to refloat sinking ships using air-filled tanks.

6. Digging tortoise

Tenth-century writer Hero of Byzantium wrote two famous tracts on ‘siege craft’, surviving copies of which are held in the Vatican Library. These manuals, called ‘poliorcetica’, were the early medieval world’s authoritative guides to siege engineering and siege warfare.

This tract describes a range of siege engines and weapons. One machine was known as a digging tortoise. A sort of large mobile shed, it would be brought up to the walls of a city or castle by an attacking force. It would sometimes be covered with animal hides to protect it from any sand or oil the defenders threw down on it. The ‘tortoise’ would then give attacking sappers the cover to employ battering rams to weaken the walls, or to use borers to drill into them.

7. Iron crow

One peculiar but not uncommon sight at a siege in England in the Middle Ages was a large device resembling a fishing rod, called a crow. This machine would have been mounted on to the defenders’ walls and used to snare and then ‘reel in’ enemy soldiers, particularly those on horseback. Once hooked, the unfortunate knight would be hoisted into the castle walls and ransomed.

A famous incident involving an iron crow occurred at the Siege of Ludlow in 1139 when King Stephen saved Prince Henry of Scotland from being winched away from his horse by one of these fearsome ferrous fishing rods.

8. Hellburners

At the Siege of Antwerp in 1585 jobbing Italian military engineer, Federigo Giambelli unleashed a fearsome new weapon of war which sent shockwaves around Europe.

The Habsburgs’ local lackey the Duke of Parma had been sent to quash rebels in the Flemish city the previous year.

Elizabeth I of England, supporting the resisters, engaged the services of Giambelli. His devasting ‘machines’ nearly resulted in victory for the defenders of the port city. What was it that wreaked havoc on besieging Spanish forces? Why, exploding ships, of course.

Nicknamed ‘hellburners’, some have referred to these floating bombs as the world’s first ‘weapons of mass destruction’.

Two large ships of over 60 tons were converted for the purpose. Over three tones of gunpowder were placed in the hold of each ship, and a clockwork detonator was created. The huge explosion of one hellburner was said to have killed over a thousand Spanish troops and created a hole wide enough in the attackers’ blockading pontoon bridge to enable a fleet to sail in. The naval relief never took the opportunity created by the hellburner to aid the city, and in August of 1585, the Spanish prevailed over the local insurgents.

9. The lantern shield

While strictly a personal weapon as opposed to a siege engine or artillery piece, this Swiss Army knife of medieval weapons clearly meets the definition of a ‘contraption’. Dating from Renaissance Italy, the cleverly-named lantern shield was a buckler (small shield) with a lantern fitted to it. It was designed for use in duels and as protection for those who braved Italian city streets at night.

The shield’s lantern may have been used to dazzle muggers, but if that failed the implement also had attached to it a gauntlet with serrated teeth, a dagger, and spikes.

Weird and wacky innovation has always been a part of warfare, and military engineering continues to attract designers who are keen to create either life-preserving equipment or destructive weapons. Intriguingly, some of the designs and ideas mentioned here, such as the submarine, resurfaced (ahem) in later centuries.