Melt two ounces of butter in a saucepan on a slow fire, with three tablespoonfuls of flour to thicken. Stir well, not letting it brown; then moisten with one pint of white broth (No. 99), beating constantly, and cook for ten minutes. Dilute three egg yolks separately in a bowl ; pour the sauce over the eggs, a very little at a time ; strain through a Chinese strainer, and finish with half an ounce of good butter and the juce of half a lemon, taking care that it does not boil a second time.