One of the greatest hazards in Mount's Bay was the sudden shift from southwards to south–west. Ships comming up the Channel would be blown into the bay; those entering or leaving the bay would be pinned up against the eastern cliffs, and chaos would reign off Mullion where scores of ships and boats would be anchored. In 1862, four wrecks alone were caused by such veering gales.

In 1867, after two days of a furious gale, ship after ship stood shelter under Mullion cliffs; then on the night of 5 January the wind veered SSW. A frantic scramble ensued as nineteen schooners raised anchor and headed to sea. Two ships collided, the Margaret and the Cherub. One of the crew of the Margaret leaped unto the Cherub only to find she was crippled and uncontrollable. He was able to come ashore with her crew. The Margaret was slightly damaged in the bows and lay at anchor with three other schooners. The weather turned sunny and clear an the gale dropped to a light breeze; but the barometer was falling, a heavy ground sea broke on the beach, and the tide was ebbing away beneath them. The Margaret was beyond rocket range so a messenger was sent to Porthleven for a lifeboat. When the men on shore realized it would take too long for Porthleven to answer, they sent another message to the Lizard.

The would be rescuers attempted for the Margaret's crew to float a line ashore, but the crew seemed ignorant of its peril and stood leaning on the bulwarks blithely waiting for rescue. At almost dead low water the ship parted her cable, broached to, broke in two amidships and disintegrated. The captain clung to some of the wreckage but failed to reach rocket lines shot to him, and was swept away.

The other schooners lay out further in safety. One, the Hearty took off the crew of the iron schooner Ebbw Vale and eventually landed them safely at Plymouth. The Ebbw Vale broke her cable in the rising south–west gale that evening and drove in close two the other two wrecks.