Preheat oven to 375°.
Grease a 2 quart casserole dish.
In a mixing bowl, sift flour, sugar, salt, and baking powder; stir in caraway seeds.
Cut in butter until mixture resembles coarse meal.
Stir in Raisins.
In a separate bowl, combine buttermilk 1 egg, and baking soda.
Stir into flour mixture just long enough to moisten ingredients.
Place on floured board and knead lightly until dough is smooth.
Form into a ball and place in greased 2 quart casserole dish.
Use a sharp knife to cut a 4" cross about ½" deep in the center of the dough on top.
Brush top with egg yolk.
Bake at 375° for 1 hour, or until toothpick inserted in center comes out clean.
Cool bread on wire rack in casserole dish for 10 minutes.
Remove from casserole dish and continue cooling on wire rack.
To cut, divide loaf in quarters. Thinly slice each quarter.