PGmc adverbs update
Fragment of a discussion from User talk:Rua
Final -a is not preserved in any Germanic language that has a body of any decent size. It's only found in Proto-Norse runic inscriptions, and those attest only a few words.
As far as I know, the preposition was just *an. The final vowels were proper to the adverbial forms, which is detailed in the paper.
I'm sorry, I have confused myself here. So the preposition *ana, ("on, onto"), should only be Proto-Germanic *an? And I meant, did the form giving Gothic, Old High German, Old Dutch and Old Saxon *ana, ("on, onto") come from a variant of *an, possibly adverbial?