Wooden double-hulled sailing vessels Invention II and Experiment.
Designed by Sir William Perry - essentially like a catamaran.
Invention II was built at Arklow 1663, said to be with two clinker-built hulls
and able to carry 30 men.
Experiment was built at Deptford, launched late 1664, of 60ft length and carried 16 guns.
Experiment was lost in the Bay of Biscay returning from Porto in a storm in October 1665.
Sir William Petty was an English polymath - he made contributions
to surveying (of Ireland), economics and ship design,...
Petty had designed a first twin-hulled boat by fixing two narrow hulls
together and rigging it with one huge sail. Launched in Dublin Bay in 1662,
his first prototype was only one and three quarters tons and had two
cylindrical hollow hulls 20 ft long and 2ft diameter. It was called
Invention. The Royal Society organised a race in Dublin Bay with 3 other vessels
- Petty's vessel won comfortably.
His second catamaran was built in 1663 at Arklow with two
more conventional clinker-built hulls. It weighed 30 tons and
possessed two decks. It was named The Invention II.
On 13 July 1663, Pepys wrote that Petty's catamaran
...hath this month won a wager of £50 in sailing between Dublin and Holyhead with the pacquett-boat, the best ship or vessel the King hath here; and he offers to lay with any ship of the world. It is about 30 tons burden, and carries 30 men, with good accommodation (as much more as any ship of her burden), and so any vessel of this figure shall carry more men, with better accommodation by half, than any other ship. This carries also ten guns, of about five tons weigh. In their coming back from Holyhead they started together, and this vessel came to Dublin by five at night, and the pacquett-boat not before eight the next morning; and when they come, they did believe this vessel had been drowned, or at least left behind, not thinking she could have lived in that sea. Strange things are told of this vessel.
Perry was invited to sail Invention II to Portsmouth - to challenging the king's yachts in a race. Instead he sailed to Dover and then Deptford where he arrived in January 1664. Here she was visited by Pepys:
..and so to Deptford, and there viewed Sir W. Petty's vessel; which hath an odd appearance, but not such as people do make of it, for I am of the opinion that he would never have discoursed so much of it, if it were not better than other vessels, and so I believe that he was abused the other day, as he is now, by tongues that I am sure speak before they know anything good or bad of her. I am sorry to find his ingenuity discouraged so.Perry challenged the king to a race - but this was declined. He did, however, secure funding for a third vessel.
Image of a model of the vessel, Experiment, as presented to the Royal Society:
The Experiment, said to carry 16 guns, seems to have been built at Deptford. The king and the Duke of York were present at the launch [at Redriffe (Rotherhithe), in December 1664] when the vessel was observed to swim finely with an odd appearance though not so odd as people said it was.
The Experiment made her maiden voyage from London to Oporto in April 1665, thence to Vigo in May. Experiment did not leave on her return journey until late October 1665, when she foundered in the Bay of Biscay with the loss of all hands (17 men). Although Perry blamed the loss on lack of crew, since some were impressed, the actual design was too top-heavy and so the vessel was unstable. The second vessel, Invention II, was inherently more stable and had performed better.
John Evelyn, in his diary [1675 March 22], gave a good description of Petty's catamaran when he wrote,
Sir William, amongst other inventions, was author of the double-bottom'd ship, which tho' it perish'd, and he was censur'd for rashnesse, being lost in the Bay of Biscay in a storme when, I think, 15 other vessells miscarried. The vessell was flat-bottom'd, of exceeding use to put into shallow ports, and ride over small depths of water. It consisted of 2 distinct keeles crampt together with huge timbers, &c. so as that a violent streame ran betweene; it bare a monstrous broad saile, and he still persists that it is practicable and of exceeding use; and he has often told me he would adventure himselfe in such another, could he procure sailors, and his Majestys permission to make a second Experiment, which name the King gave it at the launching.
Sir William could not get the king's permission to build another ship because the Experiment had been lost and her model was unsafe and dangerous.