Institutio Oratoria
Quintilian
Quintilian. Institutio Oratoria, Volume 1-4. Butler, Harold Edgeworth, translator. Cambridge, Mass; London: Harvard University Press, William Heinemann Ltd., 1920-1922.
On the other hand, hiatus is not to be regarded as so very terrible a crime: in fact I do not know which is the worse fault in this connexion, carelessness or a pedantic
On the other hand Demosthenes and Cicero show a sense of proportion in the way in which they face the problem. For the coalescence of two letters, known as συναλοιφή, may make our language run more smoothly than if every word closed with its own vowel, while sometimes hiatus may even prove becoming and create an impression of grandeur, as in the following case, pulchra oratione ista iacta te. [*](Boast yourself of that fine speech of yours.) For syllables which are naturally long and rich in sound gain something from the time which intervenes between two vowels, as though there were a perceptible pause.