1. Preheat oven to 325 degrees. Butter two 5-by-9-inch loaf pans. Combine 3 1/4 cups all-purpose flour and salt in a bowl.

2. Cream butter and sugar with a mixer on high speed until pale and fluffy, for 8 minutes. Scrape down sides of bowl. Reduce speed to medium, and add vanilla extract.

3. Lightly beat eggs, and add to mixer bowl in 4 additions, mixing thoroughly after each and scraping down sides. Reduce speed to low, and add flour mixture in 4 additions, mixing until just incorporated. Toss raisins in remaining 2 tablespoons flour; fold into finished batter. Divide batter in half. Fold cinnamon into 1 half. Scoop batters into 2 prepared pans, 1/2 cup at a time, alternating plain and cinnamon. Swirl with a knife. Tap on counter to distribute; smooth tops.

4. Bake until a tester inserted into center of each cake comes out clean, about 65 minutes. Let cool in pans on a wire rack for 30 minutes. Remove from pans, and let cool completely on wire rack.

5. Make the glaze: Combine 2 cups confectioners' sugar and 4 to 5 tablespoons milk in a bowl. Drizzle over cooled cakes.