In June 1792, the scientists of the time cared about to know the exact measurement of the metre. Rodez would be a "central" element to accomplish this measure. Indeed, Jean Baptiste Joseph Delambre was responsible for measuring the distance from Dunkirk to Rodez, while Pierre Méchain was the one measuring between Barcelona and Rodez. They were to meet in Rodez to combine their results and determine the value of the metre. In 1793, at Montjouy in Barcelona, Méchain detected an inconsistency between the recorded lengths and an astronomical survey of the position of the stars. The Franco-Spanish war prevented him from repeating measurements. This difference (which was in fact not due to a handling error but the uncertainty of the instruments used) plunged him into deep trouble and he made every effort to avoid having to report on his work in Paris. In 1799, he resigned himself to attend an international conference which welcomed his scientific work. In 1798, the was created.