Pierre Vernier

Pierre Vernier (1580 to 1637) was a mathematician and instrument inventor from Ornans in Franche-Comté, then ruled by the Spanish Habsburgs, and the inventor and eponym of the vernier scale. Taught science by his father, he became captain and castellan of the castle at Ornans for the King of Spain and later a councillor and director general of economy in the County of Burgundy. In 1631 he published in Brussels a treatise on the new mathematical quadrant, dedicated to the Infanta, in which he described a movable sector of thirty equal divisions set against a quadrant scaled in half degrees, so that minutes could be read by finding which division lines coincide. Christopher Clavius had mentioned the idea before, but not as a permanent attachment. The name vernier was given by Jérôme Lalande, who showed that the older name nonius belonged to a different device.