It is used to amplify small variations of length. DataInventory Number: MES01Date: 1900 (c.)Dimensions: Diameter : 17cmInstrument Categories: Measures PlacesLocation: Μουσείο Φυσικών Επιστημών και Τεχνολογίας, Πανεπιστήμιο Αθηνών - Museum of Science and Technology, University of AthensOrigin: Πανεπιστήμιο Αθηνών - Φιλοσοφική Σχολή / University of Athens - Faculty of Philosophy