This was the reason why in 1889 by the 1st General Conference on Weights and Measures (CGPM) of the Bureau International des Poids et Mesures (BIPM) the three characteristics length, mass, and time were selected and in 1954 during the 10th CGPM three more characteristics were added and it was decided to derive an International System of Units (SI) that should cover all physical characteristics.
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In 1892−93 the Michelson interferometer was used to determine the length of the metre in terms of the wavelength of the red line of cadmium.