The merchant seaman was at the stern-rail, unhooking the fish they'd caught on the long-lines trailing behind the ship, when the explosion blew him overboard....
He had shipped aboard on this tramp steamer as a last resort. An American, he'd had to do some fast talking to get a berth on this Uruguayan vessel. But they were short-handed, and needed experienced engine-room hands. He'd used his Texas beer-joint Spanish to get by.
They were carrying a load of tires from Yokohama to São Paulo, Brazil; shipments were hard to come by for this old bucket, and she'd carry few more. The engine-room was a pure mechanical disaster; but he and the Chief Engineer had, by dint and din, kept her running so far....
When he had been able to marshal his senses, he found himself awash in a sea of tires; some charred, most not. Looking around, he finally saw the bow of the steamer slowly slipping beneath the waves. He grabbed a shrink-wrapped truck tire for flotation and considered his few options.
Treading water for a short while, he listened carefully for voices but heard none. Perhaps he was the only survivor! It had been mid-morning when the ship exploded, so he had plenty of daylight left to swim to safety – IF there was any safety to be had....
Fortunately, the seas were not high; although there was about a five-foot swell running, light and variable winds had not built up dangerous waves. He looked around, each time the swell lifted him to its crest, searching for – anything: land, another ship, whatever. Although he was not an officer, and had no knowledge of the ship's course or even its approximate location, he knew they'd been planning to get into the Atlantic and the coast of Brazil via the Panama Canal. Surely, there must be considerable maritime traffic between Japan and the Canal... perhaps his best choice was to try to remain afloat the best he could, and wait to be rescued.
After a few hours had passed, the man began to lose patience, leaving him vulnerable to losing hope. Not a ship, not a plane, not even a bird had he seen! Maybe a more pro-active course would be preferable... the sun was definitely lowering in the sky now; he'd better decide soon.