Sunday, 22 March 2020


Just what Hieron II wanted with a monster grain freighter requires some explanation.
Why should an hellenistic monarch seek to extol his own and his kingdom's power and virtue by means of a massive maritime corn carrier ? 

South eastern Sicily is fertile. It was also under peaceful control of Hieron. It was a grain basket of the ancient world.  In the mid 3rd century BC there was much money to be made from selling corn abroad or largesse to be shown by giving it away to places with poorer agriculture or smitten by war pestilence or earthquake. If Hieron could safely despatch corn around the Mediterranean there was a fortune to be made.

Hieron made a name for humself by attacking the Mamertines. This was a public service because these were a collection of brigands slaves pirates and freebooter who had settled in the city of Messana. The Mamertines called themselves 'the people of the war god' after Mamers an Oscan war god.The menfolk of Messana were descendents of mercenaries hired by the tyrant Agathokles, himself an infamous  fore-runner of Hieron at Syracuse. They gained the city by murdering the citizens one night and siezing their women and treasure. Their subsequent behaviourtowards the neighbours was no better. Forget ideas about Johnny Depp in big boots and a bandana. Mediterranean pirates of the classical world ranked with the lowest form of humanity to emerge anywhere.

Mamertine warrior c. 220AD - could be Mamer?
Being an island and a colony of Corinth it was vital for Syracuse to keep the sea lanes open. If piratical activity became to intense the island was effectively blockaded. Mamertine and Tyrrhenian pirates harassed Hiero's trade but they were difficult to eradicate.
a pirate galley intercepts a grain freighter : Attic vase c.450BC

So for Hieron moving his grain safely was a big deal.

To move grain safely by sea requires certain things of the transporter.

Size : better to move a lot in 1 go - the hamster foraging  principle.


Speed- do it fast to avoid predators - again a lesson from hamsters. A longer hull gives higher speed .

Stability - bulk cargo is dangerous to move in bad weather. A broad stable hull is better. (Also for wealthy passengers...)

Bulk carrier Stellar Banner after cargo of ore shifted
Defence - pirates could descend in hoards. Any freighter had to be able to defend itself against several other ships and perhaps hundreds of attackers.

Manouverability - this would be limited by the size of the ship but the ability to manoeuvre into harbour was vital,  or to evade pursuers.

Servicability - the hull and rig should be robust and not require anything out of the ordinary to keep it in running order.

All of these factors mitigate for a large ship rather than a small fast one or a flock of small ones.

Galleys were reliably fast and could sail through calm but they had a limited freight capacity in their slim shallow hulls and so the ship should obviously be a sailing ship or 'round ship' 'strongylos'.


Just how big was this 'monstrous mass' ?

From Athenaeus we get to know the following:
  • it required the wood for 60 triremes to construct the whole thing
  •  the sacred trireme built by Antigonos and victorious off Kos was not a quarter of Syracousia
In addition we can note that
  • the Nemi vessels, the largest found, are 70mx30m and 73m x24m 
  • grain freighter Isis from Lucan's poem 'The Wishes' , 55m by 13.5m or so, hold 4 - 5m deep
  • Caligula's obelisk-transporter was 104m long -  but only made 1 voyage
  • Ptolemy II's '40' could have been about 100 metres long 
  • Ptolemy IV's Thalemagos was 30 cubits by half a stadion i.e c.15m by 90m !!
  • longest wooden ships without steel bracing < 80m WIKI LIST HERE
Largest wooden ship - Wyoming in 1917 - 140m x 15.5m : ships this big had steel hull bracing (still failed)
Taking the wood used first. If we consider the project as a 3 dimensional mass of wood with a similar density of wood involved within the whole structure then 60 times the mass of a trireme from Coates this would be about 30 tonnes of wood.So...30 x 60 = 1800 tonnes.

The trireme occupies circa 35m by 6m by 4 m of space.840m3

840 cubic metres x 60 is 50,400.

If we take the cube root of this we can get the block equivalent of the monster...Yes, very simplified...

The cube root is 36.Double the length to half the width and get the profile more elongate.

Interestingly, if we double the length we get about the length of the Nemi ships. And the longest modern era wooden ships.

We must then halve another dimension, shall we use the height, to get an 18m high structure.

This ballpark model is a block 72metres long by 36metres wide and 18metres high.

Very rough, and we should expect more wood goes to strengthening the hull and reducing the interior volume. If we reduce the interior volume by a quarter, conservative, to allow for a heavier structure, we have our block model as 65metres by 32metres by 16metres. Or so.

Now, typically, sailing freighters have a length to breadth ratio around 4:1. As per the Nemi ships which were for use on a confined lake, this falls to 3:1 or less.


WARSHIPS  L:B RATIO                                   CARGO SHIPS   L:B RATIO
Ladby                   7.4                                         Klåstad                          4.4
Hedeby 1              11.4                                       Skuldelev 6                   4.48
Roskilde 6             9.3                                        Skuldelev 3                   4.24
Skuldelev 5          7                                            Skuldelev 1                   3.44
Sludelev 2            7.5                                         Hedby 3                        3.55

Aslak - Ladby replica and Nidhug( L:B 4)


Kyrenia Ship   2.5
Isis                   4.5
Nemi 1              3
Nemi 2              3.5
trieres Olympias  7

The same relationship holds.

But our ship must sail the high seas so we must drop the width of 36m down somewhat to a quarter of 65 i.e. 16metres. Following the block model would now mean we stretch the heigh to maintain the timber mass...adding a third or so to the height to give keel to top deck height of 20metres or so.

Mackintosh et al (Syracusia as a giant cargo vessel, IJNA 1999) arrive at dimensions of 61.5metres  length   15.5metres beam  by 10metres high. Not a million miles away.

So we have a length and beam that is useable. I will take 64metres and 16 metres as nice round figures to base my model upon.

The rather top-heavy figure of 20 metres for keel-to-top deck can be controlled by Athenaeus' statements that there were three exterior gangways - parados - plus a hold.  This means 3 decks with ceilings (terrestrial use of the word..) at 2 to 2.5 metres. and a hold of simliar depth would give 10 metres keel to top. Height above water level would therefore be around 7 metres ?

If the topsides were too high then Vasa-Mary Rose syndrome could occur.

Vasa had a poop deck 19 metres above the keel and c.15m above the waterline. In addition, it had a very high centre of gravity. Ancient ships tended to have little superstructure, keeping their centre of gravity low. There was no incentive to have several decks for guns and massively strong superstructure.
 A schooner of similar dimensions from 1920 was c.8m waterline to deck.

A similar sclae vessel for comparison can be provided by the French 118 gun Ocean class warships from c.1800. Larger than the Victory, these were 3-deckers with similar domensions to our prospective Syracousia. at  65.18 metres by 16.25m in beam. They were massive platforms for 118 cannon and survived in service until 1860 or so.
Ocean class 118 gun French warship c. 1800 
These ships stood about 10.5 metres from the waterline to the poop deck.
Their holds were 5 metres deep - most below the waterline.
They had four deck levels above the waterline but these had overheads at under 2 metres each.
These would not be appropriate for the Syracousia which had to accommodate high status guests and had luxurious fittings.

All in all 11 metres over the waterline would seem to be a maximum for a ship of these general proportions.


Erring on a slightly larger 'monstrous mass' I decided to go for the following dimensions.


This gives a hull more seaworthy than the Nemi ships, which, although built with the same quality as a sea-going ship are essentially barges not intended to be exposed to waves or swell. or to move under sail. Thus, ot as enormous as the greatest dimensions we know of from the classical world but somehwat according to modern era giants.

The large size of the hull allows stability, higher speed under sail and the carrying of sufficient defences to hold off pirates.

Equivalent of Syrakousia and pirates : 'Standy by to repel boarders!'
 FIGHTING PIRATES : just have to watch again..... HERE  and HERE

Next we will work out the ship's lines.

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