Bob, Here is a link with the explaination: http://bobbuethe.tripod.com/cartoonacy/qanda/q_smokey.htm --- Rollei List - Post to rollei_list@xxxxxxxxxxxxx - Subscribe at rollei_list-request@xxxxxxxxxxxxx with 'subscribe' in the subject field OR by logging into www.freelists.org - Unsubscribe at rollei_list-request@xxxxxxxxxxxxx with 'unsubscribe' in the subject field OR by logging into www.freelists.org - Online, searchable archives are available at http://www.freelists.org/archives/rollei_list