In the fourth century Latin verse showed distinctly side by side two rhythms. Quantitative verse, long confirmed by Greek example and often directly imitative of Greek models, held the field of culture. The verse of Horace, Vergil, Ovid, it imposed itself upon all educated poets. Its influence controlled the schools through the archaistic teaching of style; and its quantitative prosody continued for centuries to be taught as part of _grammatica_. But all this while another rhythm was heard from the mouths of soldiers in songs of marching beat. What is somewhat indefinitely known as Saturnian verse moved beneath and behind literature, sometimes broke in half-conscious echoes through learned poetry, then gained the ground lost by literary standards, and finally won recognition as valid poetry in the hymns.[24] Eventually the manuals of metric, which in any age proverbially lag behind current habit, distinguished the new verse by a new application of an old name. They called it _rhythmus_. The ancient quantitative verse is generally referred to in the middle age as _metrum_ (_metra_, _metricus_, etc.); the new Latin verse, as _rhythmus_ (_rithmus_, _rithmicus_, etc.). Bede’s _De arte metrica_, written early in the eighth century and widely used as a textbook, distinguishes as follows: Rhythm is seen moreover to be like meter in that it is a harmonized pattern of words, not planned metrically, but adjusted by recurrence of syllables to the judgment of the ear, as are the songs of popular poets. Though there can be rhythm without meter, there cannot be meter without rhythm. The distinction may be stated more clearly thus: meter is regularity with harmony; rhythm is harmony without regularity. But often you will find in rhythm even regularity, kept not by the modes of [ancient] art, but by the sound and by the lead of the harmony itself. This, though popular poets must do it rudely, expert poets may do expertly. In this manner was most beautifully composed, with resemblance to iambic meter, that famous hymn Rex æterne domine, rerum creator omnium, qui eras ante sæcula semper cum patre filius, and other Ambrosians not a few. So in the fashion of trochaic meter is sung the alphabetical hymn on the day of judgment: Apparebit repentina dies magna domini, fur obscura velut nocte improvisos occupans.[25]