Prosodia Rationalis is the short title of the 1779 expanded second edition of Joshua Steele's An Essay Towards Establishing the Melody and Measure of Speech, to be Expressed and Perpetuated by Peculiar Symbols, originally published in 1775.[1] In this work Steele proposes a notation for linguistic prosody.[2] The notation is inspired by that used in music. The treatise is notable as one of the earliest works in the subject and its insight that in speech, unlike in most music, pitches slide rather than exhibit distinct tones held for lengths of time.[3]