Diptych sundials consist of two plates hinged together by a string that serves as a gnomon. These plates open to form a right angle and have a viewing hole for a compass, a pin dial signifying the time of day, symbols of the Zodiac, as well as a dial for Italian and Babylonian hours. These beautiful timepieces told the time and would fit in your pocket. These intricate, portable sundials could be set for use in various latitudes, and equipped with devices helpful for merchants and travelers in Europe. Diptych dials became popular during the 16th and 17th centuries. They were used as portable timepieces. The sun was used for telling time during the day, and the moon at night. Miller was a famous instrument maker who worked in Nuremberg.