To Fettle

What is the derivation of the verb "to fettle?" In the North it means to amend—to repair—to put a thing, which is out of order, into such a state as to effectuate, or to be effectual for, its original, or a given purpose; e.g. a cart out of order is sent to the wheelwright's to be fettled. It has been suggested that the word is a verbalised corruption of the word "effectual." Bailey, in his *Dictionary*, has designated it as a north country word: but it is evident that he misunderstood its entire meaning; for he has merely "to fettle to," and seems to have been ignorant of the use of the word…