We can trace the history of alliterative verse in England with tolerable certainty. The Anglo-Normans first brought in rhymes, which they employed in their own poetry. The adoption of this new system into the English language was gradual, but it appears to have commenced in the first half of the twelfth century. It was, at first, mixed with alliterative couplets: that is, in the same poem were used sometimes rhyming couplets, which were suddenly changed for alliterative couplets, and then, after awhile, rhyme was again brought in, and so on. Of this kind of poetry we have four very remarkable examples, the _Proverbs of King Alfred_, a poem which was certainly in existence in the first half of the twelfth century;[12] the _Early English Bestiary_;[13] the Poem on the _Debate between the Body and the Soul_;[14] and the grand work of Layamon.[15] The following lines from the Bestiary may serve as a specimen of the manner in which the two systems are intermixed; they form part of the account of the spider:-- "ðanne _r_enneð ge _r_apelike, for ge is ai _r_edi, _n_imeð anon to ðe _n_et, and _n_imeð hem ðere, _b_itterlike ge hem _b_it and here _b_ane wurðeð, _d_repeð and _d_rinkeð hire _blod_, _d_oð ge hire non oðer _god_, bute fret hire _fille_, and dareð siðen _stille_." . . . . . . "Cethegrande is a _fis_ ðe moste ðat in water _is_; ðat tu wuldes seien _get_, gef ðu it soge wan it _flet_," etc. This kind of poetry appears to have been common until the middle of the thirteenth century; after which period we only find alliteration in songs, not used in simple alliterative couplets, but mixed up in the same lines with rhyme in an irregular and playful manner.[16] But there appears little room for doubting that during the whole of this time the pure alliterative poetry was in use among the lower classes of society; and its revival towards the middle of the fourteenth century appears to have been a part of the political movement which then took place. In this point of view, the poem of Piers Ploughman becomes still more worthy of attention as a document of contemporary literary history. The old alliterative verse came so much into fashion at this period that it was adopted for the composition of long romances, of which several still remain.[17] The use of this kind of verse was continued in the fifteenth century, and was imitated in Scotland as late as the time of Dunbar, but the later writers were evidently unacquainted with the strict rules of this species of composition.