Posted by Jon on July 27, 1998 at 19:59:02:
In Reply to: Illustration Error in Swallowdale posted by Art Mulder on July 27, 1998 at 19:33:38:
Both those have been noted previously. You may want to do a search of the archives. IIRC the Secret Water error occurred sometime in the '60s when they changed plates. The Swallowdale error has AFAIK always been there.