Butter a slice of bread before you take it off the loaf; cut it about a half inch thick and remove the crusts. First of all, cover each slice with a thin layer of hard-boiled egg that has been pressed through a sieve or chopped very fine. In the center of this sandwich put the soft parts of six pickled oysters. Put the butter and flour into a little saucepan; mix without melting; add the cream, onion juice, curry and turmeric. Bring to boiling point; beat and stand away until perfectly cold. When you are ready to serve the sandwiches, cover each one with a thin layer of this sauce; put a slice of bread on top, press together, and serve. The sauce must not go over the sandwiches until you are ready to serve; and then, remember, you have but one layer between two slices of bread.