Discophone

A discophone is a magical communication device. They a small discs that can convey written messages. To use a discophone one must rub one's thumb over the disc and speak the message to be sent. When the message arrives, the discophone makes a low tone. It seems as though the discophone does not work deep underground.
As far as we know, there are only two discophones in existence. One is held by Blair MacWendell, the other by Relnwe Adiath.