It will be seen that the linguistic status of these components varies with their length. Components which are precisely the length of a phoneme, i.e. which represent merely the simultaneous breakdown of each phoneme by itself, enable us to eliminate phonemes of defective distribution and to indicate the phonetic composition of each phoneme […]. We shall also permit some components to have the length of more than one phoneme, i.e. we shall say that such a component stretches over a sequence of phonemes. When phonemes are written with such long components, we shall be able to know the limitations of distribution of any phoneme by looking at the components of which it is composed […]. Some of these long components will extend over all the phonemes of an utterance or linguistic form. These components will turn out to constitute the intonational or other contours of the language […].
- Harris (1944), a pag.181