Institutio Oratoria
Quintilian
Quintilian. Institutio Oratoria, Volume 1-4. Butler, Harold Edgeworth, translator. Cambridge, Mass; London: Harvard University Press, William Heinemann Ltd., 1920-1922.
etsi vereor,
the cadence of a verse is not suitable to the cadence of a period: compare the phrase of Cicero, Quo me vertam, nescio, [*](pro Lig. i. 1, pro Cluent. i. 4. ) which is the end of a trimeter. It matters not whether we speak of a trimeter or of a senarius, since the line has six feet and three beats. The end of a hexameter forms a yet worse conclusion; compare the following passage from the letters of Brutus: neque illi malunt halbere tutores aut defensores, quoniam causam sciunt placuiisse Catoni. [*]( They ask for no guardians or defenders since they know that the cause has won the approval of Cato. )