Related Clues:

• Old message system
• Fax ancestor
• Communications system of the past
• See 21 Across
• Send a wire
• Obsolete communication
• Fax precursor
• Fax's kin
• Fax predecessor
• Pre-fax message
• Wired message
• Inform a former spouse by wire?
• Old communications machine
• Pre-fax communication
• Make known in advance