Institutio Oratoria

some wrote ai in all cases, as in Greek, others confined its use to the dative and genitive singular; whence it comes that Vergil, [*](Aen. ix. 26 and vii. 464. ) always a passionate lover of antiquity, inserted pictai uestis and aquai in his poems.

But in the plural they used e and wrote Syllae, Galbae. Lucilius has given instructions on this point also; his instructions occupy quite a number of verses, for which the incredulous may consult his ninth book.

Again in Cicero's days and a little later, it was the almost universal practice to write a double s , whenever that letter occurred between two long vowels or after a long vowel, as for example in caussae, cassus, diuissiones. That he and Vergil both used this spelling is shown by their own autograph manuscripts.

And yet at a slightly earlier date iussi which we write with a double s was spelt with only one. Further optimnus maximus, which older writers spelt with a u, appear for the first time with an i (such at any rate is the tradition) in an inscription of Gaius Caesar. [*](Caligula, the first of the Caesars to adopt this title.)

We now write here, but I still find in manuscripts of the old comic poets phrases such as heri ad me uenit, [*]( Ter. Phorm. 36. ) and the same spelling is found in letters of Augustus written or corrected by his own hand.

Again did not Cato the censor spell dicam and faciam as dicem