Drop 8–10 apricots into boiling water, remove immediately, and turn into a sieve to drain. Skin, halve, remove the pits, and place the fruit in a saucepan. Add ⅜lb sugar, cover with a lid, and boil until tender. Rub the apricots through a fine sieve, place on ice, and stir until the purée cools and thickens. Add ½glass isinglass, mix with 1½glasses or more of whipped cream, stir thoroughly, then pile into a mold and set on ice.