Moreover, the state of the Iliad and Odyssey, in respect to the letter called the Digamma, affords a proof that they were recited for a considerable period before they were committed to writing, insomuch that the oral pronunciation underwent during the interval a sensible change.[256] At the time when these poems were composed, the Digamma was an effective consonant, and figured as such in the structure of the verse: at the time when they were committed to writing, it had ceased to be pronounced, and therefore never found a place in any of the manuscripts,—insomuch that the Alexandrine critics, though they knew of its existence in the much later poems of Alkæus and Sapphô, never recognized it in Homer. The hiatus, and the various perplexities of metre, occasioned by the loss of the Digamma, were corrected by different grammatical stratagems. But the whole history of this lost letter is very curious, and is rendered intelligible only by the supposition that the Iliad and Odyssey belonged for a wide space of time to the memory, the voice, and the ear, exclusively. [256] See this argument strongly maintained in Giese (Ueber den Æolischen Dialekt, sect. 14. p. 160, _seqq._). He notices several other particulars in the Homeric language,—the plenitude and variety of interchangeable grammatical forms,—the numerous metrical licenses, set right by appropriate oral intonations,—which indicate a language as yet not constrained by the fixity of written authority. The same line of argument is taken by O. Müller (History of the Literature of Ancient Greece, ch. iv. s. 5). Giese has shown also, in the same chapter, that all the manuscripts of Homer mentioned in the Scholia, were written in the Ionic alphabet (with Η and Ω as marks for the long vowels, and no special mark for the rough breathing), in so far as the special citations out of them enable us to verify.