Dome

Close view of Cathedral with bell tower, from northwest; Hyperboloid structures are architectural structures designed with hyperboloid geometry. Often these are tall structures such as towers where the hyperboloid geometry's structural strength is used to support an object high off the ground, however hyperboloid geometry is also often used for decorative effect as well as structural economy. The first hyperboloid structures were built by Russian engineer Vladimir Shukhov (1853-1939). In the Metropolitan Cathedral the hyperboloid structure is a result of 16 identical assembled concrete columns. These columns, having hyperbolic section and weighing 90 tons, represent two hands moving upwards to heaven. The Cathedral was dedicated on 31 May 1970. The four bronze sculptures (3 m high), represent the Evangelists and are by by Alfredo Ceschiatti (1968), as are the angels inside. Source: Wikipedia; http://en.wikipedia.org/wiki/Main_Page (accessed 12/2/2007)