Task: Question Generation
Input (English): Passage: James Weddell was an Anglo-Scottish seaman who saw service in both the Royal Navy and the merchant marine before undertaking his first voyages to Antarctic waters. In 1819, in command of the 160-ton brigantine Jane which had been adapted for whaling, he set sail for the newly discovered whaling grounds of the South Sandwich Islands. His chief interest on this voyage was in finding the "Aurora Islands", which had been reported at 53°S, 48°W by the Spanish ship Aurora in 1762.  He failed to discover this non-existent land, but his sealing activities showed a handsome profit.
In 1822 Weddell, again in command of Jane and this time accompanied by the smaller ship Beaufort, set sail for the south with instructions from his employers that, should the sealing prove barren, he was to "investigate beyond the track of former navigators". This suited Weddell's exploring instincts, and he equipped his vessel with chronometers, thermometers, compasses, barometers and charts. In January 1823 he probed the waters between the South Sandwich Islands and the South Orkney Islands, looking for new land. Finding none, he turned southward down the 40°W meridian, deep into the sea that now bears his name. The season was unusually calm, and Weddell reported that "not a particle of ice of any description was to be seen". On 20 February 1823, he reached a new Farthest South of 74°15'S, three degrees beyond Cook's former record.  Unaware that he was close to land, Weddell decided to return northward from this point, convinced that the sea continued as far as the South Pole.
Another two days' sailing would likely have brought him within sight of Coats Land, which was not discovered until 1904, by William Speirs Bruce during the Scottish National Antarctic Expedition, 1902–04. On his return to England, Weddell's claim to have exceeded Cook's record by such a margin "caused some raised eyebrows", but was soon accepted.
Output (English): What is the precise latitude measurement from which Weddell decided to return northward, convinced that the sea continued as far as the South Pole?