Encrypted Newspaper Ads in The Times: The Collinson Arctic Expedition Communication System (1850-1855)

Explore a fascinating DEF CON conference talk that uncovers the story of encrypted newspaper advertisements published in The Times between 1850-1855, designed as a secure communication system for Arctic explorer Captain Richard Collinson. Discover how these cryptographic messages, created using a modified Royal Navy signal-book cipher, served as a one-way communication channel from Collinson's family while he searched for the lost John Franklin expedition in the Canadian Arctic. Learn about the groundbreaking worldwide distribution system that allowed these encrypted messages to reach remote ports, and understand how these historical cryptograms remained unbroken until the 1990s. Follow the speakers' recent research efforts to decrypt all remaining advertisements and contextualize them within their historical and cultural framework.