Encyclop\ufffddia Britannica, Inc., headquartered in Chicago, Illinois, ...
The University of Chicago owned it at one point. It's not British any more.
You probably want to check the [link|http://dictionary.oed.com/cgi/entry/00328384/00328384spg1?query_type=misspelling&queryword=numskull&first=1&max_to_show=10&sort_type=alpha&result_place=1&search_id=XvzV-8EE1qh-68&hilite=00328384spg1|OED] ...
numbskull, n. and a.
{alpha} 1697 M. PIX Innocent Mistress IV. iii. 33 You take me for a numpscull.
HTH!
Cheers,
Scott.
(Who would use the "b" to please himselfness.)