Add the sugar, lemon slices, cloves, cinnamon stick, nutmeg, ginger and water to a large nonreactive saucepan set over medium-high heat. Stir frequently to dissolve the sugar. Let the mixture reach the boil, then turn the heat to medium, and simmer for 10 minutes. Add the brandy and ale and heat, but do not allow to boil. Serve in beer mugs, with a slice of lemon on each drink. Makes 8 (10-ounce) beer mugs.