Penny Napoleonic Wars prompted the use of base metals in 1797. Despite the decimalization of currencies in the United States and, later, throughout the British Commonwealth, the name remains in informal use. No penny is currently formally subdivided, although farthings (¼ d.), halfpennies, and half cents have previously been minted and the mill (1/10¢) remains in use as a unit of account in some contexts. "Penny" is first attested in a 1394 Scots text, a variant of Old English ', a development of numerous variations including ', ', and '. The etymology of the term "penny" is uncertain, although cognates are
Quarter tone Tui St. George Tucker, Ivan Alexandrovich Wyschnegradsky, and Iannis Xenakis. (See List of quarter tone pieces.) The term "quarter tone" can refer to a number of different intervals, all very close in size. For example, some 17th- and 18th-century theorists used the term to describe the distance between a sharp and enharmonically distinct flat in mean-tone temperaments (e.g., D–E). In the quarter-tone scale, also called 24 tone equal temperament (24-TET), the quarter tone is 50 cents, or a frequency ratio of or approximately 1.0293, and divides the octave into 24 equal steps (equal temperament). In this scale the quarter tone