Seidlitz powders

The powdery contents of both packets were stirred or dissolved separately in water and then mixed, giving off carbon dioxide with a characteristic fizzing sound.

Seidlitz powders, manufactured by numerous chemical factories from the early 19th century onwards, take their name from the village of Sedlec near Most, Czech Republic (previously in Bohemia).

Sedlec (Seidlitz) was described in an 1867 guide to European spa towns as "a wretched-looking place, hardly meriting the name of a village, and the wells - whence the water should be derived - are a few shallow, circular pits, whose contents very seldom find their way to this country [ie England]."

Though rarely used today, the term "Seidlitz powder" lives on as a lyric from the popular song "A Fine Romance" by Jerome Kern and Dorothy Fields.

One of the four clerks of Dodson and Fogg is mixing a "Seidlitz Powder," perhaps to treat a hangover, in chapter 20 of Charles Dickens' Pickwick Papers.