Sift together cornmeal, flour, and salt in a large mixing bowl.
Dissolve soda in buttermilk; add to flour mixture, stirring until well blended.
Add eggs, oil, and cracklings, stirring just until dry ingredients are moistened.
Pour batter into a well greased 10 1/2-inch cast-iron skillet. Bake at 350° for 15 minutes. Increase temperature to 425°, and bake an additional 25 minutes or until lightly browned. Cut into wedges, and serve warm with butter.