When the Church of Saint-Jacques-la-Boucherie was torn down, it was decided to preserve one of its flamboyant towers (built under the reign of Francis I), now known as the Tour de St. Jacques. There are no ornamental decorations around its base since it was formerly inside the nave, and therefore not visible. The original church was a starting point for the religious pilgrimage to Santiage de Compostela. The alchemist Nicolas Flamel was originally buried under the floor of the church. The remaining tower is also a monument to science since this is where the mathematician and inventor Blaise Pascal conducted experiments concerning atmospheric pressure in 1648.