The Silver Seal is an airship that runs from Reykjavik to London. It is a Geyik airship imported from the Ottoman Empire. The journey takes three days and cannot be done any faster, no matter how Passepartout may try to entice the captain or the engineer - unless there is enough money (12,000) or the Spherical Diamond to purchase the Silver Seal outright (this speeds it up by one day). Unable to speed up the flight, Passepartout instead spends his time preparing for he and his master's return to London after being gone for so long. After three days with no incident the airship will dock in London and the pair will immediately return to the Reform Club.