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An example of the tower window for Cologne Cathedr

Carrying out glazing work in the giddy height of 43 metres in the North tower of Cologne Cathedral certainly requires a head for heights. A total of eight tracery windows have been installed here to reconstruct the original character of the tower as it was built in 1871 and its enchanting former library on the first floor.

The colourful original designs for all eight windows were still in existence in the construction archive of the Cathedral. It is assumed that they were designed by the ‘Dombauhütte’ (Masons’ Lodge of the Cathedral). There is, however, evidence that a local enterprise did the finish in 1871/72. At the time, all the windows received coloured ornamental glazing, which were based formally on the patterns of the medieval glass windows in the high porch of the Cathedral.

In World War II the windows in the North tower were all destroyed; except for some small remaining parts in the tracery. They were later replaced by a simple rectangular glazing made of clear glass. Half a century later, it was decided to exchange functionality with styled flair.

The preparations for the reconstruction of these windows were conducted in the Mason Lodge of the Cathedral (Dombauhütte). We performed the actual work.

On approaching the original, we referred to the selection of glass and the colour shades that had been retained from the original glazing. It was decided to use an antique cathedral glass, as its surface structure came closest to the original. With regard to the colour selection it was feasible to use the standard colours available. Only in individual cases, specific shades of colour had to be melded in accordance with the original samples, in order to achieve the original window reconstruction in the powerful Neo Gothic colours.

Each of the tracery windows including the pointed arch is 16 metres high, 5.20 metres wide and consists of 52 leaded panels, each measuring 74cm x 96cm. Depending on the pattern, one individual panel comprises between 250 and 300 pieces of glass.

With this restoration part of the original design, a piece of 19th century church architecture was returned to Cologne Cathedral. This ‘new’ North steeple hall is a fine example of how craftsmanship of today is able to revive historic originals.