Bring half of the water to the boil and pour it over the lemons, peel and Sugar. Stir and leave to stand covered for a while. Add the rest of the water cold. When the liquid is lukewarm add the yeast.
Keep the mead at room temperature until it starts to ferment, i.e. about one day. Put a couple of Raisins and 1 tsp of Sugar into clean bottles, and strain the mead into the bottles. Loosely cork the bottles and store them in a cool place. The mead is ready when the Raisins rise to the surface.