Add enough water to the fruit juice to make 1 quart of liquid. Put 1 1/2 pints of this over the fire with the sugar. When boiling thicken it with the cornflour, which should be smoothed with the rest of the liquid. Stir well over the fire for 5 to 8 minutes; whip up the eggs and stir them carefully into the mixture so as not to curdle them. Pour all into a wetted mould, let it get cold, turn it out, and serve.