Diagram of a Nocturnal, an instrument used to determine time at night by the stars. Dated 18th Century Stock Photo - Alamy
File:Nocturnal howto.svg - Wikimedia Commons
Jamestown Settlement & American Revolution Museum at Yorktown - The nocturnal was an instrument used by 17th century navigators to determine time at night. The wooden instrument is engraved with the months
Pocket Nocturnal by Kala - The most charming timepiece of its time
Nocturnal | Canada Science and Technology Museum
Nocturnal Geocoin™
BBC - A History of the World - Object : Nocturnal or Nightdial