Lecture hall

Meridian viewers are small openings in a window or wall that cast a spot of light on a marked north-south line on the floor. This allows for determining noon and the solar solstices.

The placement of meridian viewers was mandated by law in February 1836 through a Royal Decree. This was at the request of Adolphe Quetelet, who was tasked with the precise determination of time for Belgium. Meridian viewers were installed in places such as Antwerp, Bruges, Liège, and in the aula of Ghent.

In July 1836, the famous Belgian mathematician Adolphe Quetelet established the Meridian line in the St. Gudula Church in Brussels. You can still go and see that copper line. Together with the light spot, you can determine noon yourself. Under the leg of Louis II of Hungary, depicted in the stained glass window, the light spot is placed. This spot casts a beam of light onto the copper line at noon. It is best to be there an hour or two before noon (depending on whether it is summer time or winter time), as you will see that the actual noon does not correspond with 12 o'clock on your watch.

Dromos