Franklin Taylor, A Dictionary of Music and Musicians (1900)
“ TRANSPOSITION, change of key, the notation or performance of a musical composition in a different key from that in which it is written. When it is said that a piece of music is in a certain key, it is understood that it consists of the notes of a certain scale, and that, except chromatic passing-notes and suchlike melodic changes, no note can be employed which is not a part of that scale. ”
