This section is from the book "Mrs. Rorer's Vegetable Cookery And Meat Substitutes", by Sarah Tyson Rorer. Also available from Amazon: Mrs. Rorer's Vegetable Cookery And Meat Substitutes.......
All the ordinary sauces are very easily made, if one will adhere strictly to the measurements and directions for putting them together. I will repeat that all measurements here are level, and it requires two level tablespoonfuls of flour to properly thicken each half pint of liquid. Sauces should not be boiled any length of time, or the butter will separate, making a greasy sauce. When directions tell you to bring them just to boiling-point, it means to take them from the fire the moment they boil. Disobedience to rules, or carelessness, always produces bad results.
A small gravy strainer should be kept near the stove, or in the table drawer, to be used only for straining sauces. It is wise to train your cook, or make it a rule for yourself, to always strain a sauce. It is sure then to be smooth.