Church Saint Sulpice, Paris. Meridienne - Church Saint - Sulpice, Paris. The meridian line and...

Church Saint Sulpice, Paris. Meridienne - Church Saint - Sulpice, Paris. The meridian line and the obelisk - Established in 1744 by Claude Langlois under the direction of astronomer Pierre Charles Le Monnier, the meridian consists of a 40.3 m long copper band, which starts from a marble slab in the south transept and joins the obelisque in the north transept. A lens placed in the stained glass window of the south transept allows the Sun to illuminate the Meridian. At the summer solstice, a bright spot illuminates the marble slab; at the winter solstice, the light spot illuminates the obelisque