Fondation de la Haute Horlogerie

Glossary

Universal hour

One twenty-fourth of the universal day which begins at midnight at the Prime Meridian at Greenwich. Following the 1884 International Meridian Conference in Washington, the Earth was divided into twenty-four time zones, each covering 15 degrees longitude measured from the Greenwich meridian. Subsequently, universal time replaced the multiple times based on local meridians. Until 1911, France continued to use the Paris meridian as the basis for its time.

• french: Heure universelle
• japanese: 標準時／ヒョウジュンジ
• chinese: 国际标准时