I noticed today that Apple Mail keeps a copy of all gmail email messages in the Library/Mail folder. Over time this has accumulated to over 8GB. The GMail accounts are set up as iMap accounts. I delete whatever messages I do not want to save and expunge from GMAIL. Seems GMail also dumps these into the ALL MAIL folder. Even if I clean that out, the email messages stay in the Library/mail folders. Does anyone know how to prevent Apple Mail from archiving the iMap email messages in the Library/Mail folders?