Double whole note either of two ways: by a hollow oval note head, like a whole note, with one or two vertical lines on either side, as on the left of the image, or as the rectangular shape also found in older notation, shown in the middle of the image (; ). Because it lasts longer than a bar in most modern time signatures in common use, the breve is rarely encountered except in English music, where the half-note is often used as the beat unit . A related symbol is the double whole rest (double rest or breve rest), which usually denotes
Two hundred fifty-sixth note long as the two hundred fifty-sixth note. After this would come the one thousand twenty-fourth note (eight flags or beams), the two thousand forty-eighth note (nine flags or beams), the four thousand ninety-sixth note (ten flags or beams), and so on indefinitely, with each note half the length of its predecessor. The shortest note value to have ever been used in a published work is the 1024th note (notated incorrectly as a 2048th) in Anthony Philip Heinrich's "Toccata Grande Cromatica" from "The Sylviad", Set 2, written around 1825; 256th notes occur frequently in this piece, and some 512th notes also