Place the stock in a clean saucepan, set it over a brisk fire. When
boiling, add the white of one egg to each quart of stock, proceeding
as follows: beat the whites of the eggs up well in a little water;
then add a little hot stock; beat to a froth and pour gradually into
the pot; then beat the whole hard and long; allow it to boil up once,
and immediately remove and strain through a thin flannel cloth.