Vedic Metre in its Historical Development c12.s3.97

c12.s3.97

(iii) Final -o represents a phonetic developement of ā, incapable of combination or shortening, certainly in átho, probably also in mó and nó. The genuineness of the form átho is shewn first by its appearing only in the popular Rigveda and the Atharvaveda, whereas all revisions of the text of the Rigveda have been carried through the whole of it: and secondly by its use before vowels and consonants alike, although in the latter case no metrical advantage is obtained. Again átho does not stand for áthā ū, for in no instance is it equivalent to áthā ū with hiatus, and it cannot be equivalent to áthā ū combined in the Atharvaveda, for in that case there would be almost as many occurrences of the particle ū in this one combination as in all other possible positions, which is contrary to the principle of quantitative evidence. It follows that *átho* is a real phonetic developement of *áthā*; and, if so, it is impossible that the later tendency to shorten the word to *átha* can have been at work at this period.