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.......
Put the uncooked yolks of two or three eggs in a clean cold soup-dish; add a half saltspoonful of salt and a dash of cayenne. With a fork or spatula work all these well together and add, a teaspoonful at a time, a half pint of olive oil. Stir constantly and rapidly while adding the oil. Be careful to thoroughly incorporate each teaspoonful of oil before adding the next. Stir in at last one tablespoonful of vinegar or lemon juice. In warm weather, chill the eggs and the oil before mixing and stand the plate on ice. This dressing will keep several days if closely covered.
Too much vinegar or lemon juice thins the dressing. If a slightly sour salad is wanted, season the salad materials, not the dressing.
Whipped cream may be added to mayonnaise when it is ready to be used. The cream must be well whipped and drained or it will thin the mayonnaise.
Make a mayonnaise dressing, selecting light-colored eggs, and use lemon juice instead of vinegar. When the dressing is finished, add a drop of green coloring and a half pint of cream whipped to a stiff froth. This is used for Waldorf, yellow tomato and pineapple salad.