Reduce well one pint of espagnole (No. 414), adding slowly to it one gill of veal blond (No. 423), or chicken stock (No. 195) and a few truffle parings; when the sauce is well reduced, incorporate into it by degrees, two gills of Madeira wine or any other preferred. As soon as the sauce is finished, pass through a tammy and keep warm in a bain-marie.
A classic Escoffier-era wine sauce that assumes you already have a pot of espagnole on the stove. The whole character of it rests on when the wine goes in.
Charles Ranhofer published The Epicurean in 1894 after decades as chef at Delmonico's in New York, and its sauce chapter is essentially the French classical repertoire as it was practised in an American grand restaurant: a handful of mother sauces, then dozens of numbered derivatives built from them, each identified by the one ingredient that distinguishes it. Madeira sauce is the most durable of the wine derivatives, and its prominence reflects the trade rather than any French terroir. Madeira, sherry and Marsala are all fortified wines that survived long sea voyages and warm storage without spoiling, which made them staples of nineteenth-century American and British cellars long after table wines had become reliably available. That the recipe casually offers Xeres or Marsala as equals shows how interchangeably a professional kitchen treated them. In modern terms this sauce sits within what Escoffier would soon codify as sauce madere, a demi-glace finished with wine, and the family it heads includes sauce Perigueux when truffle is added in earnest rather than as parings.