Pour the dripping, if hot, into a saucepanful of boiling water; (if cold, break it up in small pieces and put these in the boiling water;) let it boil up, and then boil for fifteen minutes, stirring it now and again; then pour it all into a large basin, and leave it till perfectly cold, when the dripping will have formed a thick, firm white cake, from the under side of which the impurities, blacks, etc., can easily be scraped. Dripping thus prepared keeps well, and the operation can be repeated several times as long as the fat is not allowed to burn. It is more economical to let dripping cool before adding water, as it always contains a portion of rich gravy, which would be wasted if it is poured direct into the boiling water.