The Potosi belonged to a fleet of legends. F. Laeisz gave every ship a name beginning with P, and the firm's fast, immaculately run sailing vessels became famous worldwide as the Flying P-Liners, described by one chronicler as without doubt the most successful fleet of sail ever assembled under a single flag. They ran the nitrate trade, hauling saltpetre from the west coast of South America back to Germany, where it was turned into fertiliser and explosives, and the run demanded ships that could survive Cape Horn again and again. The discipline of the line was such that, across countless voyages, none of the four- or five-masted Laeisz ships was ever lost or dismasted in a Horn storm. Named for the silver-rich Bolivian city of Potosí, then reckoned the highest city in the world, this barque was among the fleet's brightest stars.

Almost everything about the Potosi was steel: her black hull with its white waterline, her masts, her yards, even much of her rigging drawn into cable. Four of her five masts were square-rigged, each carrying six sails in towering tiers, while the aftermost mast bore fore-and-aft sails. All told she set forty-three sails over a sail area of more than fifty-six thousand square feet. She was a three-island ship, with a raised midship structure the sailors called the Liverpool house, where the captain and crew found dry quarters and the main double wheel stood high above the deck, shielded from the seas that swept her in heavy weather. Only six windjammers of this exact five-masted barque rig were ever built; the Potosi was one of the finest of them.

The ship was the brainchild of Robert Hilgendorf, the most celebrated of the Laeisz captains, who shaped her design and then sailed her as her first master. Under his hand she set records on the saltpetre run. In good conditions the Potosi could touch nineteen knots, and on her best single day, in 1900 with Hilgendorf commanding, she logged 376 nautical miles in twenty-four hours, an astonishing distance under sail alone. Manned by a crew of around forty, she made twenty-seven round voyages between Hamburg and Chile from 1895 to 1914 under five captains. Of the entire Flying P fleet, only her near-sister Preussen, a true five-masted full-rigged ship, was faster, and the Preussen paid for that speed in handling. The Potosi was the rare combination of enormous and nimble.

The war ended her German career. Caught at Valparaíso when the First World War broke out in 1914, she was interned, and afterward handed to France as reparation; sold on, she passed eventually to a Chilean firm in Valparaíso and was renamed Flora. Her end came in 1925. On 15 September, bound for Cape Horn, she caught fire off the Patagonian coast northwest of the Falklands. Her captain set course for the Argentine port of Comodoro Rivadavia and reached the roads on 18 September, anchoring offshore to fight the flames. The fire could not be beaten. On 19 October 1925, the Argentine cruiser Patria put the burning hull down with gunfire, and one of the greatest sailing ships ever built went to the bottom of the South Atlantic, ended not by the Horn she had mastered so often, but by fire and a few rounds of artillery.