SYRAKOUSIA VII : MY WHAT A BIG ONE!

A most remarkable part of Syrakousia's armament was the great catapult which was designed by Archimedes himself.

A wall with battlements and decks athwart the ship was built on supports; on this stood a stone-hurler, which could shoot by its own power a stone weighing one hundred and eighty pounds or a javelin eighteen feet long. 

The exact nature of the 'wall' with its 'battlements' is difficult to decide. It cannot conflict with the masts and it cannot conflict with the operation of the sails. 

The logical solution is that Moschion is describing a fortified forecastle. 

The first naval application of  artillery we have record of was by Demetrios (soon to be Poliorketes) of Macedon was the mounting of light bolt shooters - probably tension weapons - in the forecastles of his war-galleys. 75years before, on a massive grain freighter, the logical process of where to put such a contraption must have been startlingly apparent to a genius like Archimedes. 

The forecastle was an area easily put off limits to passengers.
 The shooting arc of a weapon mounted there would be more than 180 degrees. 
The weapon would be protected by the forecastle defences and be able to shoot into any vessel barring the passage of the freighter.

CASTLEY FORECASTLES

The best place to see fortified forecastles is on Trajan's Column.

These are light Liburnian-style galleys but they have very decorative forecastles. These cannot have been high or they would catch the wind and block vision. They were bulwarks men could take cover behind.

(see HERE for misinterpretation of these forecastles as being 6 metres or so high!)

This kind of thing would be very practical to mount a catapult behind and be an impressive and decorative addition to the ship. It just needs a Greekised appearance rather than the Roman ornament of the Trajanic ships. Maybe some surviving Greek fortifications could give a good starting point for the model.

The Dipylon gate at Athens

See more 3D reconstructions from Athens HERE at Ancient  Athens 3D. Lots of modelling fuel!

So we have a good idea of the location and positioning of the catapult.

ARCHIMEDES' BEAST

The weapon itself ... was large. The usual pictures of Imperial Roman Legionaries serving their handy ballistae show weapons shooting 1 cubit bolts. Archimedes' catapult shot a bolt TEN times larger. The stock, where the bolt was laid needed to be ten cubits plus ..  meaning the weapon was 7 metres or so long!

By Archimede's time the best catapults were torsion powered. The energy for the shot was stored in wound-up sinew and hair skeins mounted in a massive frame. The limbs were pulled back to create the tension and when they were released they rotated back to their original position - incidentally flinging a deadly projectile at one's foes.

Something in this order..but we shall see not quite the same

It is significant that the machine is described as shooting BOTH a stone ball and a bolt. It was simultaneously an oxybeles - arrow shooter, and a lithobolos - stone-shooter. Only the most advanced types of catapult could do this - here we see the mark of Archimedes again.

The first catapults used simple tension for driving force

The first torsion catapults had limbs which rotated outside of the springs and backwards as they were tensioned. When released they shot outward and forward. These were known as euthytone - straight stretched - machines. The largest arrow they could shoot was about 3 cubits or 1.25 metres long.

The more advanced machines had springs set wider apart and the limbs rotated first forward and inward - and then backward as they were tensioned. They then moved forward and outward as they were released. This method of tensioning allowed a greater angle of rotation and more power to be stored in the tension spring. Palintones, as they were known - meaning backward stretched - could shoot both arrows and stones and could be built to great size.

a palintone stone/arrow shooter

Thus we can decide the machine to be built looks a bit different ot the commonly made type of model and it was certainly not a mangonel or trebuchet-style contraption!

Artillerist's delight : when the arm breaks does it fly towards me or away?

Interestingly, the torsion catapult has no recoil, It does not throw itself across the deck or shake the foundation it stands upon. The mangonel-onager was named after the wild ass for a reason ....

The catapult stood on a secure trestle mounting which allowed it to be rotated and elevated-depressed. The mount was simple but solid. There was no sophisticated ranging apparatus because , despite what a lot of 'experts' spout - there is no evidence that catapults were used at anything but close range where the trajectory of flight was flat and the thing could be aimed. High-arcing shots had ZERO chance of hitting a target in a naval battle. (unles you interpret the Antykythera mechanism as an early rangekeeping and position-prediction device!).

trajectories for a large palintone

A machine of Syrakousia-size would have a flattish trajectory extending out to 200 metres. From the height of Syrakousia's top deck this would be certainly accurate out to 100 metres or so.

The ammunition was a large arrow 18 feet long or a stone ball - not a tatty random rock! - 40 centimetres oe so in diameter! The stone-cranes mounted on the towers could use a 1 talent - 25Kg ball which would be around 30cm diameter. Perhaps the catapult could use these at close range and shoot lighter balls to longer range.

 POINT AND SHOOT

This magnificent device was sitting on a platform on top of the third deck of a ship. It would not necessarily stay put in all weathers. Nor could  it be trained to all angles without being moved.

The usual mounting was a solid adjustable trestle-style thing which was necessarily quite solid.

It could not be easily moved without special arrangements. It could allow aiming in altitude and azimuth.

The best analogy I can find is the deck mounted carronade of Nelsonian date. The massive wooden carriage was made fast against recoiling and adjusted in azimuth by means of various blocks and tackle.

Cannon tackle on USS Constitution

Carronade deck mounting

A similar arrangement was used in Hellenistic artillery defence towers to shift catapults between apertures. It would be perfect to secure a large catapult on a ship's deck and allow it to be trained for shooting.

Archimedes monster could have been on a mounting which was easily shifted to different points on the

artillery deck where it was located. Then from each point it could be accurately trained with some finer adjustment on the weapon itself.

Hellenistic artillery installation

The weapon need be served only by a few men if the block and tackles system was used, say 6 or 8.

This aspect of ancient artillery is often overlooked in illustration. The precision of the action in an ancient catapult was remarkable, and very useful to batter a hole in a wall. But they should also be trainable by some means.

Big cat. No apparent means of aiming it. Actually of the same size as Syrakousia's

EFFECT

The maximum range of ancient catapults was about 700 metres but a heavy type shooting stones of 90 kilos or so would probably have a maximum range half this. But this is not the whole story.

At sea, a maximum range shot, between two moving points would be so unlikely to hit on its necessarily high trajectory that it would be a waste of finely carved stone balls.

The key part of an ancient catapult's range was the distance it could be used with a relatively flat trajectory. This makes the thing easier to aim and the projectile flies faster.

The artillery officer on Syrakousia probably aimed at (Careful! Howerd is having an influence!  Ed.) engaging targets at 200 metres and less. However, the siting of the machine 8 metres or so up on a ship with masts and other structures meant that its field of fire was limited.

The usual siting for catapults on a Hellenistic war-galley was the bow. The ship would shoot at targets it ws running towards or following. It could force enemy vessels out of its path. This is probably how Syrakousia's catapult was mounted too.

ONWARD TO THE CONSTRUCTION!