Institutio Oratoria

Quintilian

Quintilian. Institutio Oratoria, Volume 1-4. Butler, Harold Edgeworth, translator. Cambridge, Mass; London: Harvard University Press, William Heinemann Ltd., 1920-1922.

But eloquence cannot be confined even to these three forms of style. For just as the third style is intermediate between the grand and the plain style, so each of these three are separated by interspaces

v10-12 p.489

which are occupied by intermediate styles compounded of the two which he on either side.