History of modern period domes

New production techniques allowed for cast iron and wrought iron to be produced both in larger quantities and at relatively low prices during the Industrial Revolution. Iron was used in place of wood where fire resistance was a priority. In Russia, which had large supplies of iron, some of the earliest examples of the material's architectural use can be found. Andrey Voronikhin built a large wrought iron dome over Kazan Cathedral in Saint Petersburg. Built between 1806 and 1811, the 17.7 meter wide outer dome of the cathedral was one of the earliest iron domes.

Although iron production in France lagged behind Britain, the government was eager to foster the development of its domestic iron industry. In 1808, the government of Napoleon approved a plan to replace the burnt down wooden dome of the Halle au Blé granary in Paris with a dome of iron and glass, the "earliest example of metal with glass in a dome". The dome was 37 meters in diameter and used 51 cast iron ribs to converge on a wrought iron compression ring 11 meters wide containing a glass and wrought iron skylight. The outer surface of the dome was covered with copper, with additional windows cut near the dome's base to admit more light during an 1838 modification. Cast-iron domes were particularly popular in France.

An early example from Britain is the fanciful iron-framed dome over the central building of the Royal Pavilion in Brighton, begun in 1815 by John Nash, the personal architect of King George IV.

In 1828, the eastern crossing tower of Mainz Cathedral was rebuilt by Georg Moller with a wrought iron dome. The dome was made of flat iron sections and reinforced with ties that passed through the interior of the dome. Such dome reinforcement was one of the two established techniques, the other being the use of a combination of horizontal rings and vertical ribs. It was later removed in favor of the current structure.

Saint Isaac's Cathedral, in Saint Petersburg, was built by 1842 with one of the largest domes in Europe. A cast iron dome nearly 26 meters wide, it had a technically advanced triple-shell design with iron trusses reminiscent of St. Paul's Cathedral in London. Also reminiscent of St. Paul's dome and that of the Panthéon in Paris, both of which the original designer had visited, the dome of St. Nicholas' Church in Potsdam was added to the building from 1843-49. A dome was included as a possibility in the original late Neoclassical design of 1830, but as a wooden construction. Iron was used instead by the later architects.

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