I suppose it is safe to say that at the date of the Norman Conquest measured music did not exist. Rhythmical music there must have been from the earliest times, music of the dance, music of the march; but no system had been invented by which the duration of musical sounds could be presented to the eye. The reason for this may perhaps be found in the close association that existed between music and language, and the fact that in this association music was formerly the handmaid, not, as now, the mistress. The ancient subordination of music to language still survives in the plain-song of the Church, which, for this very reason, remains to the present day unmeasured.