Shock and awe: Thomas Phillips and the Hellburner Infernal, 1693

Thomas Phillips illustrated the famous Legge Report, a survey of the Channel islands completed in 1680. His return to the island he had so carefully studied was to prove fatal to him.

The Legge Report, or the King's Survey of the Channel Islands, 1680; A portrait of Phillips, painted in 1692/3, just before the fatal expedition, is in the National Maritime Museum.

Chief engineer in the ordnance train in the summer expedition of the British fleet against the coast of France in 1693, Phillips sailed with Captain John Benbow in the Norwich to the rendezvous of the squadron at Guernsey, and from there set out to St Malo, with the aim of ending the menace of French privateering. He was in charge of the bombs, and in particular the Hellburner ship-bomb, an Italian-Dutch surface torpedo of particular nastiness, known as an 'infernal'. It was a fireship, but loaded with a fearsome selection of explosives including 20,000 pounds of gunpowder, which he took to the foot of the wall of the fort at St Malo, where it got stuck in the wrong place. He set it on fire... That this Infernal had probably been moored off St Peter Port, its contents likely unbeknown to the inhabitants, is another thing entirely!

The London Chronicle, July 8, 1758:

An Account of an Expedition against the Coast of France in the Reign of King William III.

On the 13th of November, 1693, seven years after the Revolution, King William sent out a fleet of twelve men-of-war, under the command of Captain Benbow. A new galleon of 300 tons burthen was so contrived as to be itself one great bomb, capable of being discharged wherever she could float. In the hold of this galleon, next the keel, were stowed one hundred barrels of powder, covered with a flooring of thick timber; and on the top was laid 300 carcasses, consisting of grenades, cannon bullets, chain shot, great bars of iron, and an incredible variety of other combustible matter; which produced a fire, that, according to the report of the French at that time, and of the author of a late naval history, could not be quenched but by hot water.

With this machine, which from its office was called the Infernal, the fleet set sail from Guernsey, the public being utterly ignorant of its destination. At four o'clock in the afternoon of the 18th of November, they anchored before one of the entrances into the port of the city called La Conchal; upon the front of which was an unfinished fort, called Quince Fort. About eleven o'clock, preparations were made for striking the great blow by playing off the Infernal. An engineer [i.e. Phillips] being put on board, carried her under full sail to the foot of the wall where she was to be fixed, notwithstanding all the fire of the place directed against him; but it happened that the wind, suddenly veering, forced him off before the vessel could be secured; and drove her upon a rock within pistol shot of the place where she was to have been moored. All possible attempts were made to get clear of this rock, but without effect. And the engineer, finding that the vessel had sustained damage by the shock, and began to open, set fire to her and left her. The sea-water that broke in prevented some of her carcasses from taking fire; but the vessel soon after blew up, with an explosion that shook the whole city like an earthquake, uncovered above 300 houses, threw down the greatest part of the wall towards the sea, and broke all the glass, china, and earthenware, for three leagues round. The consternation of the people was so great, that a small number of troops might have taken possession of the place without resistance, but there was not a soldier on board the fleet. The sailors, however, demolished Quince Fort, and, having done considerable damage to the town, the fleet returned to England.

The intention was to have fastened the Infernal to the walls of the town and thus to have destroyed most of the houses. The potential enormity of the explosion was never realised, however, as the powder became wet once the ship was holed. These 'explosion ships,' that were known generically as Infernals, were Admiral Benbow's pet project, but although they were used on a few more occasions they seem to have been quietly dropped from the armoury of the British Navy. The original Dutch explosion ship of 1585, which slew 800 Spaniards in one fell swoop, had used a clockwork mechanism. Smollet's History of England in three volumes describes the St Malo explosion thus:

A capstan that weighed two hundred pounds was transported into the place, and falling upon a house, levelled it to the ground; the greatest part of the wall towards the sea tumbled down; and the inhabitants were overwhelmed with consternation, so that a small number of troops might have taken possession without resistance, but there was not a soldier on board. Nevertheless the sailors took and demolished Quince-fort, and did considerable damage to the town of St. Maloes, which had been a nest of privateers that infested the English commerce.

The blast was nevertheless huge, and Phillips must have been sailing away from the ship when it detonated.

'Whether Phillips was hurt or became ill from anxiety or excitement is not known, but he died on board Benbow's ship on the return of the squadron to Guernsey roads on the evening of 22 November 1693.' [Dictionary of National Biography, Thomas Phillips.]