I found Eleanor Creesy, who is hard to find, through a circumventous route. I picked up a biography that featured one of John Singer Sargent's best-known portraits, that of Mr. and Mrs. I. N. Phelps Stokes. They were a power couple of New York's Gilded age; she was a muse to several artists and he was an amateur scholar.
But that isn't the story, not yet. Mr. Phelps' family had made their fortune in shipping, running clipper ships, among them a famous one, The Flying Cloud, which set the world’s sailing record for the fastest passage between New York and San Francisco in 1851.
But that isn't the story either. It's that the Flying Cloud was navigated by Eleanor Creesy, wife of its captain Josiah Creesy, a woman whose life had prepared her for the task.
She was born and raised in the early 19th century in Marblehead, Massachusetts, where her father, a master mariner, taught her navigation--despite the puzzlement of his neighbors. She dreamed of marrying a sea captain and sailing with him, and she held out until she met Josiah Creesy in 1841.
They had a decade of collaboration before they took on the challenge of the Flying Cloud and sailed the ship from New York to San Fransisco in a record-breaking 89 days. It was universally acknowledged that Eleanor's skill in navigation was essential to setting the record.
Sadly, I can't find any image of her, only of her husband. A hidden figure indeed.