Mix the fruits. Add rum, cover and let stand overnight.
Preheat the oven to 275°F. Grease one 10-inch tube pan or two 9 x 5 x 3-inch loaf pans. Line with wax paper and grease the paper.
Combine the fruits, the nuts and 1/2 cup of the flour.
Sift together the remaining flour, mace, cinnamon and baking powder. Mix the milk with the almond extract.
Cream the butter until smooth, adding sugars gradually. Add the eggs, mix well and add the milk mixture. Add flour mixture; mix well.
Pour the batter over the fruits and nuts and mix thoroughly. Fill the pans and press batter down firmly.
Bake tube cake about 4 hours, loaves about 3 hours. Let cakes stand 30 minutes. Turn out onto a rack and peel off the paper.
Wrap cooled cakes in cheesecloth soaked in the rum. Place in a crock or deep kettle and cover tightly. As the cloth dries, dribble a little of the same liquor over it. Let ripen 1 month before frosting with a layer of each of the following two frostings. When dry, spread the milk frosting evenly with Confectioners' Sugar Icing .