On This Day – Sep 28 : Metre was defined

Image

One metre was defined as the distance between two lines on a standard bar of an alloy of platinum (Pt) with 10% iridium (Ir), measured at the melting point of ice. The original international prototype of the metre is still kept at the BIPM, Bureau International des Poids et Mesures, in Sèvres, France.

Make your lessons pop

Choose an account option to continue exploring our full range of articles and teaching resources

Free

Free access for everyone, everywhere. If you only need a few resources, start here.


What's included

  • One free teaching resource each month
  • Five free Education in Chemistry articles each month
  • Personalised email alerts and bookmarks