Combine prunes and water in a large bowl; cover and refrigerate overnight. Drain prunes, reserving 2 cups liquid.
Combine prunes, reserved liquid, sugar, lard, spices, and salt in a large saucepan. Cook over medium heat, stirring occasionally, 10 minutes or until lard melts. Remove from heat, and let cool.
Sift together flour and soda in a medium mixing bowl; add prune mixture and eggs, stirring just until dry ingredients are moistened.
Pour batter into 2 greased 9- x 5- x 3-inch loaf pans. Bake at 350° for 1 hour or until a wooden pick inserted in center comes out clean. Cool in pans 10 minutes; remove from pans, and cool completely on wire racks.