PREPOSITIONS. Of redundant
Of is sometimes redundant before relatives and relatival words in dependent sentences, mostly after verbs intransitive.“Make choice of which your highness will see first.
”
“What it should be . . . I cannot dream of.
”
“Making just report
Of how unnatural and bemadding sorrow
The king hath cause to plain.
”
where, however, "whence" is, perhaps, loosely used for "what place," and of strictly used for "from." The redundant and appositional of, which we still use after "town," "city," "valley," &c., is used after "river" (as sometimes by Chaucer and Mandeville) in“He desires to know of you of whence you are,
”
“The river of Cydnus.
”