Nonius (device)

Pedro Nunes Nonius model

Nonius is a measuring tool used in navigation and astronomy named in honour of its inventor, Pedro Nunes (Latin: Petrus Nonius),[1] a Portuguese author, mathematician and navigator. The nonius was created in 1542 as a system for taking finer measurements on circular instruments such as the astrolabe. The system was eventually adapted into the Vernier scale in 1631 by the French mathematician Pierre Vernier.[2]

  1. ^ "Pedro Nunes". Infopédia [em linha]. Porto: Porto Editora. 2015.
  2. ^ Poelje, Otto van (25 July 2004). "Diagonals and Transversals: Magnifying the Scale" (PDF). Journal of the Oughtred Society: 22–28. Retrieved 2 May 2017.