Combine 3 cups flour, yeast, sugar, salt, and soda. Heat water and milk until very warm (120-130 degrees). Add to dry mixture. Beat well. Stir in remaining flour to make a stiff batter. Spoon into 2 loaf pans greased and sprinkled with cornmeal. Sprinkle tops with cornmeal. Cover and let rise 45 minutes in a warm place. Bake at 400 degrees for 25 minutes. Remove from pan. Cool.