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Tuesday, 13 September 2011

Ramblings about the Mary Rose and Renaissance ships and innovations

I posted this elsewhere on September 25th when the news reference was current....
With the Mary Rose in the news on the BBC albeit in a somewhat second hand way [the headline being about the wreck that revealed the Mary Rose, the Royal George, sunk 1782] I was reminded what a tremendous experience it was seeing it raised.
Most pictures taken from 'Cogs, Caravels and Galleons' edited by Robert Gardiner, Conway,  1994, an excellent book.  The Mary Rose picture, from the Anthony Anthony rolls courtesy of Wickipedia



We had a TV brought into assembly at school and when it was time for morning lessons, those of us who were interested were permitted to skip lessons and repair to the TV room to continue watching - a rare dispensation.  Fortunately, as the room was one of the smaller classrooms, there weren't many of us; but it made a sufficient impact on me that it began a lifelong love affair with the Mary Rose, which is why the second Felicia and Robin book, 'The Mary Rose Mystery' is about the building of this iconic ship.  Her sister ship laid down at the same time was the Peter Pomegranate and both featured the innovation of gun ports on a lower deck.

It remains a mystery who invented the idea of gun ports; both British and French claim the distinction and it is a fact that Scottish warships also sported them within a year or two at least when fighting the English fleet. The suggestion that it was a French invention arises in a 19th century [French] document so I am inclined to consider this dubious at best.

Ships of the time were undergoing many new innovations.  The older type of ship, the cog, had developed from the Viking Longships, and were clinker built, that is the hull, or skin, was built first with timbers that overlapped with frames added afterwards.  The type of ship building that had originated in the Mediterranean was carvel building, whereby a frame was built first, then the hull added with the timbers abutting. It allowed a larger ship to be built. The Lateen rig of sails was also a Mediterranean innovation that allowed a ship to go close to the wind, but was only suitable for small ships in relatively calm waters. Cogs carried square rigged sails, carracks, which were recognisable by their thick main mast had mostly square sails but carried a fore-and-aft rig on the mizzen (after) mast.  Some early carracks had only one main mast, larger ones carried three or even four masts.


Ships still had fore and after castles as platforms for archers and arquebusiers.  The majority of what cannon there were, were cast in bronze; there was no standardisation and each class of cannon could cover a wide range of calibres.   Casting in iron was impractical as the techniques of the time were insufficient; there was a tendency for the melt to 'honeycomb' as it cooled, causing disastrous explosions of the cannon when they were fired.  Henry VIII did have experimental iron foundries for canon which led, towards the end of his reign, to the first successful cast iron cannons.  Wrought iron cannons made in pieces were made, but the bronze cannon were safer and more reliable even though wrought iron cannons cheaper to produce. 
 Note the bands holding together the wrought iron cannon [above]; those below are bronze sakers



is probable that the ‘Sovereign’, Henry VII's and later Henry VIII's flag ship was retro-fitted with gunports between its building in 1488 and the date of an inventory in 1514 when the ordinance calibre is noted as being increased.  It is reasonable to suppose that this occurred during its rebuild in 1509, probably on the orders of Henry VII, who died in April of that year. (Remembering that at this time the New Year began on March 25th, Lady Day, but that the orders for a refit would have been issued some time earlier.) Henry VIII was an ambitious shipbuilder who used his fleet for ‘gunboat diplomacy’.

One more point about innovation; the 'Mary Rose' and 'Peter Pomegranate' were built in a dry dock in Portsmouth which was a pretty new concept: I leave it to Felicia to explain in an extract from 'The Mary Rose Mystery'

    “I was thoroughly intrigued by the ingeniously contrived ‘dry docks’ built by the late Henry VII  I had never heard of any such thing before.  They are cut into the bank, and dock gates used to close them off.  Then water is pumped out of that enclosed area wherein the ship is to be built, using pumping engines of a singular design.  Master Robin is of the opinion that the engines are based on the principle of Archimedes’ screw; but such an advantageous device is kept a deep secret of the craft, and even my intrepid master has not yet managed to penetrate the pumping house. 

      It may be seen that by this method, work may continue unhampered by the state of the tide.  Indeed, the whole dock lays beneath the level of the water, so that by letting the water back in slowly, the ship may even be launched without the sea level being a matter of import.

    I declare that I might, myself, have felt a little nervous working there, lest the dam wall give way.  I imagine that the workers get used to it.”

 shipbuilding - an illustration of building Noah's Ark from the Nuremburg Chronicle

Some more information on shipbuilding of the time may be found at http://brunelleschi.imss.fi.it/michaelofrhodes/about.html



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