Boil one cup of granulated sugar and one fourth cup of water until the syrup threads. In the meantime cook one fourth cup of sugar to the caramel stage; add one or two tablespoonfuls of boiling water and cook until the caramel is dissolved. When the first sugar and water are boiled to the thread stage add the liquid caramel, and if not now at the thread stage continue cooking until that stage is reached, then pour in a fine stream on to the white of one egg beaten until very foamy but not dry. Beat occasionally until cold, then spread a part over the cake and with forcing bag and tube "pipe" the remainder upon the cake. This icing is particularly good for a nut cake. Nuts may also be added to the icing.