Blanch chicken in boiling water 6 minutes, skimming any scum from the surface. Drain well. Rub it inside and out with the salt and stuff with a mixture of the ginger, crumbled stock cube, onion and gherkins. Put the stuffed chicken in a flameproof casserole with 5 cups water. Bring to the boil; then put the casserole in the oven, preheated to 180 C. Cook for 1 hour 20 minutes, turning the chicken once. Take the chicken out and arrange the cabbage wedges in the liquid place the chicken on top. Return the casserole to the oven and cook for a further 40 minutes, Serve straight from the casserole or from a large warmed tureen.