Measure of All Things

In June 1792, amidst the chaos of the French Revolution, two intrepid astronomers set out in opposite directions on an extraordinary journey. Starting in Paris, Jean-Baptiste-Joseph Delambre would make his way north to Dunkirk, while Pierre-François-André Méchain voyaged south to Barcelona. Their mission was to measure the world, and their findings would help define the meter as one ten-millionth ...