City : Brussels
Address : Baudouin I lane
Postal code : 1000
place : At the top of a building
Year of the sundial : 2003
Project leader : Architect Clernaux and Pinon
Type : Vertical
Remark :
Computing: Willy Leenders (time and date lines) and Jan De Graeve (geographic data)
The façade of the building, which is more or less facing south-west, is made of three parts: the left and right parts are flat while then central part is half of a cylinder. Inside this hollow part, the fourth of a cylinder, resides a sundial. It is about 6,5m broad and 3,3m high and covers the fifth to the sixth floor. A bowl generates the shadow.
A sundial on the outside of a cylinder was already described by Vitruvus and can be commonly found as shepherd sundial’ as they are called. Using the inside of a cylinder, as it is the case in Brussels, is very seldom.
The time indicated at the bottom is for summer. The 12 shown at the top is for winter. The bystander will merely notice that the time has to be adapter in summer with a value ranging from -6min up to +6min.
There are three date lines on the table, one for the beginning of the summer (bottom), one for the beginning of the winter (top) and one for the beginning of spring and autumn (in between).
On an aesthetic point of view this cylinder form presents some advantages: the sundial is compact. Should a flat sundial be constructed with the same distance from the bowl, the same time lines and the same date lines then the dimensions would have been 58m broad and 16m high.
Furthermore this sundial is very likely the greatest vertical sundial in the country.

3 pictures for this sundial:








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