This section is from the book "The Steward's Handbook And Guide To Party Catering", by Jessup Whitehead. Also available from Amazon: Larousse Gastronomique.
"There are two schools of cookery in France, as distinct from one another as the langue d'Oil is distinct from langue d'Oc. There is the kitchen of the North - and of Paris - in which butter is the principal vehicle; and there is the kitchen of the South - or Midi - in which oil is the chief assimilator; and the most trustworthy authorities on French gastronomy have always held that the cuisine au beurre was far more conducive to digestion than the cuisine a I'huile." Such is the theory deduced from cookery books but, in fact, butter is excessively dear in Paris and very little is used in cooking. The need of it is lessened by the employment of gravies and sauces instead, and for frying' oil, beef suet and lard are used. In the United States cotton seed oil is becoming the principal medium for frying. The cheapness of an article soon leads to a trial and adoption without regard to arguments.The cheapest grades of cotton seed oil give out an unpleasant smell and taste when heated but the better grades do not, it is but a question of quality and price; and much of the lard used by those who ob ject to the oil is but the same oil in disguise. (See Cotton Seed Oil Lard, Imitat. on Butter.) The Jews who fry much fish use oil for frying, it is, or has been, neat's foot oil, but "vegetable oil" now takes the place of that " Potato chips" and French fried potatoes are now advertised as being fried without the use of lard - meaning that oil is used.
The hotel steward buys oil by the barrel and satisfies himself by previous trial of a small lot whether it is sufficiently refined for his purpose.