In a large bowl, combine flour, sugar, soda and salt. Cut in butter with a pastry blender or rub with fingers until fine crumbs form. MIx in caraway and raisins, add buttermilk for dough. Stir until evenly moistened. Gather douth into a ball and knead about 16 turns on a lightly floured board. Pat into a smooth ball, then into a falt 1 inch think round. Place on agresed 12 by 15 inch baking sheet. Slash an X about 1/4 inch deep completely across each round; brush with remaining buttermilk. Bake in a 375F oven until deep golden, 30 to 35 minutes. Serve warm or cool. Cut into wedges. Note: If you cannot obtain buttermilk, you can use a mixture of "natural" yogurt and home-made sour milk (add some drops of lemon juice to milk and leave it for 15 minutes.)