Belgioioso lost 1783

Wooden full-rigged ship, built Liverpool 1782, 840 tons, for the East India Trade
Armed with 28 guns; 3 decks; copper-bottoomed.
Owned, crewed and insured in Liverpool, but registered in Imperial Germany
Also known as Comte de Belgioioso [in Lloyds Register as Count de Belgidso]
Belgioioso is a town South of Milan and the Count was an Austrian Diplomat in the Habsburg Monarchy.
Cargo: 350 tons of lead, silver in specie[coins] and ingots, baled goods, a consignment of valuable clocks, jewellery, and a large quantity of the valuable root, ginseng. Value: £130,000 including 100,000 silver dollars.
Left Liverpool on maiden voyage 4 March 1783, destination Canton.
Commander Charles de Coninck; master Pierce; 147 aboard including 12 cabin passengers.
Early on 5th March, driven on Kish Bank (6 miles off Irish coast) and wrecked, all lost.
Her masts were still above water, and attempts were made to salvage her valuable cargo using diving bells.
Location of wreck not now known.

Salvage - diving bells
  The wreck was 6 miles offshore with masts showing on the Kish sand bank - off the Irish coast between Bray and Dublin. In good weather, it was easily accessible by boat from Wicklow, Bray, Dun Laoghaire(Dunleary at that time) and Dublin.

To reach the barrels of silver, diving bells were used. In 1691, Edmond Halley had completed plans for a greatly improved diving bell, capable of remaining submerged for extended periods of time, and fitted with a window for the purpose of undersea exploration. The atmosphere was replenished by way of weighted barrels of air sent down from the surface. Halley and five companions dived to 60 feet in the River Thames, and remained there for over an hour and a half.
  In 1775, Charles Spalding, an Edinburgh confectioner, improved on Edmond Halley's design by adding a system of balance-weights to ease the raising and lowering of the bell, along with a series of ropes for signaling to the surface crew. The redesigned diving bell weighed 200 lb and could accommodate two divers. Spalding also added ropes inside in the bell as seats and thick glass windows to admit light. In 1782, he was able to recover 6 iron 12-pounder guns and 9 brass 12-pounder guns from the wreck of the H.M.S. Royal George in 65ft depth at Spithead.
  Spalding turned his attention to the wreck of the Belgioioso. The cargo of the Belgioioso was valued at £150,000, with £30,000 in silver and lead. The salvage terms, agreed to by the owners, were that Spalding would keep one-fourth of all silver and lead recovered and one-half of all other cargo. Additionally, if Spalding failed to recover anything, his entire expense for the operation would be defrayed.
  Spalding and his nephew, Ebenezer Watson, arrived in Dublin in May 1783 to begin their dive preparations. On 1 June 1783 they began their dives, making three dives to 7 fathoms to the wreck. Typical for the start of a new project, the three dives were plagued with issues. On the morning of 2 June 1783, Spalding and Watson resumed diving. Approximately one hour and fifteen minutes had elapsed when the boat crew became concerned. Two to three barrels of air had been sent down with no progress signal from the bell. Since the dive time was longer than usual, the dive crew proceeded to lift the bell. When the bell broke the surface they found both men dead, "Mr. Spalding reclining on his breast over one of the ropes that was stretched across for the purpose of sitting upon, and Mr. Watson sitting erect in the upper part of the bell".
  An inquest into Spalding's and Watson's deaths was eventually held. The causes reviewed during the hearings varied from the negligence of the dive ship's captain, equipment failure, including tangled signal ropes or the failure of the final cask of air reaching the divers, diver error, putrified air from the rotting cargo of the Belgioioso, even sabotage and alcohol. Dive experts today think the most plausible explanation is "a highly noxious effluvia entering the bell which could have come from the putrifying bodies or even the rotting cargo of ginseng plants in the cargo hold." This theory is consistent with the observation that they made no apparent attempt to make an emergency ascent.

Salvage work continued after this tragedy. One report describes the African divers who next attempted salvage. Africans had a reputation as very able divers - able to free dive to significant depths - as well as work from diving bells:

From: WEEKLY ENTERTAINER for MONDAY September 15 1783

The following Particulars relative to the Proceedings of the AFRICAN DIVER at the Wreck of the BELGIOIOSO EAST INDIAMAN will recommend themselves to our Readers by the Graces of Novelty as well as by the very interesting Events they contain.

HAVING sailed from Dunleary on Wednesday evening, the 13th ult., [13 August 1783], they steered for the wreck and, as they had previously placed a buoy on her, they expected no difficult in finding her out, the weather being fine and moderate with the additional pleasure of moon-light, but in this they were cruelly disappointed, for the piratical marauders of the coast between Bray and Wicklow, who have been continuing their depredations on the foundered ship ever since the melancholy disaster, had not only carried the buoys off but cut away every thing above the water's edge, mast and all, which could in the least serve as a direction. In consequence of this, a considerable part of the next day was spent finding her out, when, at length, they brought to and moored their vessel nearly alongside the wreck. It was now too late to do any work below, however he harnessed his carriage and went down to view her. She is docked deep in the sand, lying chiefly on one side, her keel is off, though her hull keeps together and her rigging is spread abroad in confused and entangled heaps on the sand, he saw but one body and a prodigious multitude of fish. Her cables, anchors, and sails, he saw very faintly and all in a recoverable situation. The chests of dollars (with which she is chiefly laden) have buoys and buoy ropes to them which are always coiled up and made fast to the chest and on any appearance of real danger, it is the gunner's duty to see those chests and ropes placed in such a manner that, in case of ship wreck, the buoys may serve as a direction and means of recovery and, had not this officer failed in that part of his duty, through the precipitancy of his fate in the moment of horror, it is more than probable some of the chests might have been raised.

[Whether the unfortunate Belgioioso was an Imperial East Indiaman, or, what is more probable, from the complexion of the times, English property, under the sanction of the emperor's flag, it matters not to the present purpose. It is agreed, she was bound to Canton in China at which place it has been a custom, time immemorial, for the trading ships of all nations to purchase their cargoes in ready money, a few articles of merchandize only excepted, which are lead for their tea chests, flints for the Porcelane manufactures, ginseng, the Chinese specific, and a little cloth, particularly scarlet. Experience has proved that Spanish dollars are found to bear the most value and to be a more profitable and certain medium than any other specie in Chinese traffic; and it is remarked in Mercantile Speculations, book II, that the gold of all nations is considerably below par in China]

On Friday morning, every thing being prepared, he sank with his bell directly at slack water ebb with one barrel of air in company and a rope to make fast or sling any thing which he thought worthy of sending up. He remained below twenty five minutes and, in that time, sent up part of the boltsprit[sic, bowsprit] rigging. He descended again, and continued under water thirty one minutes, sending up all the rigging he could clear at that part of the ship. This immergement concluded his first day's work.

Saturday the 16th, he made three immersions at the same time of the tide as the day before, and, by his admirable skill in sublimation, made fast three ropes, one to the main sail, one to the cable and one to the main stay. To these, they applied all their purchases and powers and hove a strain which heeled the vessel three streaks [planks, running fore-aft forming hull of vessel], without effect. Impatient of delay and desirous to remove the obstruction, our fearless diver immerged again and was observed by the frequent retrograde and progressive motions of the bell rope to be laboriously employed in clearing away. Having spent much time at this work, he at length made the signal to heave up, which was instantly owned, but, alas! could not be obeyed; the willing efforts of all hands at the capstan proving fruitless to move the bell, though the ship was hove down almost on her beam ends. The signal for life was repeatedly pulled in vain, all was confusion, anxiety and terror. One of the faithful blacks (whose station was at the line) now appeared naked on the gunwale, (with half a hundred weight in his hand in order to sink him), determined to lose his own life or save that of his beloved master; when, to the inexpressible joy and astonishment of all, he plunged from the entangled machine and with the celerity of a dolphin ascended smiling to the surface; his wife, his sister, and the Moors, appeared almost frantic with joy, the whole crew gathered round him and the agent and captain expressed their pleasure at his happy deliverance in loud terms of praise and warm acknowledgements. The fear of losing his bell was, all this time, uppermost in his mind; nor could he be prevailed upon to stay three minutes on board but, taking a boat's grapling in his hand, whose weight carried him down with great velocity, he hooked his subtransfretating[sic; submarinetransfer?] habitation on the opposite brim, turned her bottom upwards, touched the signal, and the bell and himself were both hove up together. This accident, however, obliged them to relinquish their prize for the present, for, by this time, the wind had veered far round to the southward and a heavy sea tumbling in rendered it unsafe riding at the wreck, and finding the gale freshen with great appearance of a stormy night, they thought proper to unmoor and run for Dunleary where they arrived safe the same evening.

The last report of any salvage attempt was in 1787, and it is not known if any signficant recoveries had been made by then.

The William Morris chart of Dublin bay, 1800, [West up] shows the Kish Bank as approximately 6m long and 6m offshore, running N-S, and of least depth 5 ft. Today (2020) it is in a similar place, with least depth (at LAT) of around 3m on the offshore side.
The Belgioioso had a draught, when loaded, of 21 ft (6 metres), so would have grounded on the Bank. The diving bell operation was quoted as being in 7 fathoms (13 metres). And later, the masts were still above water. Recent attempts to locate the wreck have not been successful.