Time glasses were objects resembling oversized magnifying glasses. They allowed users to look into a time stream moving at a rate different from their own. This was particularly useful in kindness facilities treating terminal patients, as the sick could experience their entire lives in a compressed time stream, while only a single day passed in absolute time. A time glass could sync up the two time streams, allowing patients and their loved ones to communicate with each other. The Doctor had one in his drawing room. (GAME: The Gunpowder Plot)