This week's Cocktail O'Clock comes to us courtesy of the new Martha Stewart Cocktails app (which you can download for 99 cents).
In a double old-fashioned glass, combine 2 peach slices, 3 blackberries, 2 large sprigs mint, 1 1/2 teaspoons honey, and 1 tablespoon fresh lemon juice. Mash gently with the back of a spoon until fruit releases juices. Add 2 ounces bourbon, 2 peach slices, and 3 blackberries. Fill glass with ice and top with seltzer.