Ha, ha! Good observation. But actually, Gord - i went with the actual spelling of the title of the book by Samuel Butler.
Over the years since i first read it in the 60's, I've heard of different reasons why it got spelled that way, the most believeable for me being that it was so spelled because it looked better in print that way: Erewhon, rather than the "correct" reverse of "nowhere" which would be spelled, erehwon.
Or, maybe it's just that the author had spelled it Erehwon and the publisher spelled it as Erewhon and it stuck that way? Anyway, nice that someone even noticed it here!
Regards, walt