Sentence:  The professor [...] had several other translations or feats of antiquarian deciphering to his credit. Indeed, I was extremely fortunate to find him in at the museum, for he planned to fly within the week to Peru where yet another task awaited his <WSD>abecedarian</WSD> talents. 
Meaning of the word marked with <WSD> tags:  Pertaining to the alphabet, or several alphabets. (Mid 17th century.)<ref name=SOED/>