This section is from the book "The Cook Book By "Oscar" Of The Waldorf", by Oscar Tschirky. Also see: How to Cook Everything.
Put two ounces of butter into a saucepan and melt it; then stir in two tablespoonfuls of flour, mixing it well over the fire, but not letting it brown at all. Pour in gradually a pint of boiling water or white stock, and continue stirring until it thickens; then put in two ounces more butter, and two tablespoonfuls of finely-chopped parsley, and season to taste with salt and pepper. When the butter has dissolved the sauce is ready for serving.
Squeeze the juice out of a lemon, remove the pips, and mince fine the pulp and rind. Wash a good handful of parsley, shake it as dry as possible, and chop it, throwing away all the stalks. Put one ounce of butter and one tablespoonful of flour in the stewpan, and stir over the fire until well mixed; then put in the parsley and minced lemon, and pour in as much clear stock as will be required to make the sauce. Season with a small quantity of pounded mace, and stir the whole over the fire for a few minutes. Beat the yolks of two eggs with two tablespoonfuls of cold stock, and move the sauce to the side of the fire, and when it has cooled a little, stir in the eggs. Stir the sauce for two minutes at the side of the fire, and it will be ready for serving.
 
Continue to: