The first thing to know is that “tow” can be another word for raw flax or hemp. These fibers are coarse but a light golden colour and vaguely resemble light blonde hair. By extension then, a “towhead” is a head full of flax fibers (blonde hair) and also the person who possesses this head.

Most American English speakers have had occasion to use the familiar idiom out of whack to describe something maladjusted or out of order. Despite the commonness of this expression, plausible theories of its origin are in short supply. One suggestion has the whack in this phrase being a synonym for a hit or blow that throws something off, like a mechanism, the car door is out of whack, or a body part, I threw my spine out of whack. Possibility number two involves the word wacky, an older dialectal word originally meaning “foolish and left-handed.” Wacky in currant usage, of course, is “crazy, odd, peculiar.” Both of these options are suspect, however, because the very phrase out of whack implies that being in whack (whatever that may be) is positive. So we look to other theories, one of which points out that an older sense of the word whack means a share, bargain, or agreement. Or perhaps whack is an onomatopoeia for an auctioneer’s hammer rap, signaling the establishment of a bargain or fair price. If you like these explanations, then something out of whack is a bad bargain or an agreement that’s gone awry. Incidentally, the fraternal-twin phrase out of kilter has an origin equally mysterious. Though the word kilter has entered most contemporary dictionaries, its etymological source, like our whack, is unknown.

The first from an American College Dicitonary (ancient!),

the second from Encarta, MSN’s encyclopedia.

It MAY be helpful, don’t know…..:(