The first place I ever read about starter was not in a cookbook or other non-fiction text, but in a historical novel:
…Amanda Whipple was up at five, teaching Mun Ki how to cook American style, and she was impressed both with his clever mind and his fearful stubbornness. For example, on each Friday during the past four decades it had been Amanda’s ritual to make the family yeast, and for the first two Fridays, Mun Ki studied to see how she performed this basic function in American cookery. He watched her grate the potato into a stone jar of almost sacred age and add a little salt and a lot of sugar, after which she poured in boiling water, allowing all to cool. Then, ceremoniously, she ladled in two tablespoonfuls of active yeast made the Friday before, and the strain continued. For forty-three years Amanda had kept one family of yeast alive, and to it she attributed her success as a cook. She was therefore appalled on Mun Ki’s third Friday to enter the cookhouse full of ritualistic fervor, only to find the stone jar already filled with next week’s yeast.
With tears in her eyes, she started to storm at Mun Ki, and he patiently listened for some minutes, then got mad. Flashing his pigtail about the kitchen he shouted that any fool could learn to make yeast in one week. He had been courteous and had studied for two weeks and now he wanted her out of the kitchen. Not understanding a word he was saying, she continued to mourn for the lost yeast, so he firmly grabbed her shoulders and ejected her onto the lawn. On Monday the new batch of yeast was as good as ever and she consoled herself philosophically: “It’s the same strain, sent forward by different hands.” Suddenly, she felt the elderly white-haired woman she was.
—James Michener, Hawaii
Note that she did not use flour to maintain the yeast. I suppose she wanted to reserve her supply of flour for actual bread, instead of discarding it as unused starter. If I'm interpreting correctly, it took three days to get from potato water to a dough that was ready to be baked. Saturday was for building a flour-based starter, then the dough had a long, slow rise—being a missionary, she wouldn't have worked on Sunday—and baked on Monday. Janet