Charcoal.—Sieve carefully together 1lb. of fine,
dry flour and 4oz. finest “willow” charcoal, and mix it all to
a stiff paste with a little water, stirred in gradually; 1oz. or
2oz. of sugar may be added to the mixture, but it is better
without. Roll the paste out half an inch thick, cut it into
squares, etc., and bake in a sharp oven. These are best
made fresh, but will keep fairly well in an air-tight tin.