That enemy cannon- or musketballs, storms and sickness were not the only perils seamen in the eighteenth century faced was dramatically demonstrated at Spithead on August 29th 1782, when the Royal George, a First Rate of 100 guns foundered with the loss of perhaps 1400 lives.
The Royal George had been launched in 1756; at 2047 tons, she was one of the largest ships of her day. She was just in time for the start of the Seven Years' War, during which she carried Admiral Edward Boscawen's flag in the Western Squadron on blockade service, and then the flag of Admiral Sir Edward Hawke when he virtually annihilated the French fleet at the Battle of Quiberon Bay. In 1762 she went into Portsmouth for maintenance, but by the time this was complete, the war was nearly over. Instead of rejoining the Western Squadron as originally planned, she was laid up in ordinary in Plymouth. And there she remained for 16 years, manned by her standing officers while a dockyard crew was supposed to keep her in good order, but in fact did the minimum possible. In 1768 she did receive a major overhaul, but when, ten years later, she was put back into service upon the outbreak of hostilities with France in 1778, she was once again in a bad state. After some superficial repairs she rejoined the Channel fleet (as the Western squadron was now known).
In January 1781 the Royal George helped to escort a British convoy to Gibraltar and she was among a group of ships capturing two weakly protected Spanish convoys. After this adventure she eventually returned to the Hamoaze for belated repairs. In October 1780, while in the Channel, the rudder had simply dropped off her stern. At the enquiry after the disaster, Admiral Milbank said: "When the Royal George docked at Plymouth ... I saw her opened up and asked many questions. I found her condition so bad that I can't remember seeing one sound plank through the opening".
Four months later the Royal George was back in service with the Channel fleet. Before taking part in another convoy to Gibraltar, she went in to Portsmouth for some last minute repairs: a water release valve (*) in her side needed replacing. As there was insufficient time to take her into dry dock, it was necessary to heel the ship by about seven degrees to allow the caulkers to install the valve below the waterline. Instead of achieving this by attaching ropes to the masts and pulling the ship over from another ship (the normal procedure; in the event of problems, cutting the ropes would restore the ship to her normal orientation), the commanding officer, Waghorn, decided to alter the position of the centre of gravity by moving the guns on one side out, and on the other side in towards the centreline of the ship.
When the work started, not only the crew of about 850, but also some hundreds of visitors, family, friends and tradespeople were on board. A couple of hours after work started, a carpenter decided that things were starting to go wrong. After the Officer of the Watch ignored his appeal, he went to the commander, who ordered the cannon to be restored to their normal positions. But it was now too late; the angle of heel was too large and water had begun to entered the ship; the ship rapidly turned on her side and sunk. The lucky ones below could escape through the gunports: only 320 were saved. According to the Hampshire Chronicle about 1400 drowned, amongst them Rear-Admiral Richard Kempenfelt.
Although there was some suggestion that a sudden gust of wind had contributed to the disaster, and there was a large possibility that the ship had been allowed to heel over so far that open gunports came under water, the subsequent enquiry choose to conclde that some of her frames had collapsed, due to years of poor maintenance by the dock authorities. Political aspects may well have played a role here: the dockyards fell under the Navy Board, an organisation at that time (and correctly) severely criticised by the Admiralty for mismanagement and corruption.
(*) Not quite sure if this is the right word: 'zelflosser' in the Dutch translation.
This is principally taken from "Mysteries on the High Seas" by Philip MacDougall (David and Charles, 1984), incidentally with a cover painting by Geoff Hunt entitled "The last moments of the Waratah" (a steamer lost off the South African coast in 1909).