Scrub and trim potatoes, and grate. Sprinkle lightly with salt, and stir, then place in a strainer and let drain at least half an hour, stirring and pressing every ten minutes or so, to remove excess liquid.
Peel and grate onion.
Beat eggs in a large bowl, and add potatoes and onion. Stir well. Add flour, enough to help absorb some of the liquid and help the potatoes hold together.
Heat oil in a heavy pan. Form patties from the potato mixture, squeezing out excess liquid. Carefully place them in the oil. Cook about five minutes, until bottom starts to brown, and the patties hold together, then carefully turn them. After about three minutes, lower the temperature, and continue cooking until done, probably about ten minutes.
Place on paper towels to absorb excess oil.
Serve with sour cream, or apple sauce.