The 19th-century glasshouse grew out of the city-dweller's desire to bring nature and the natural into urban life. These structures became popular in urban, public, and semi-public settings. As these structures gained popularity in Europe, greenhouses began to be constructed on larger scales and of stronger materials. One engineer, Joseph Paxton (1803–1865), had an enormous effect on the development of the conservatory building type. His structures called for a system of glass and metal roof construction, whereas past structures had typically been constructed of wood and glass. His choice of materials allowed designs for glasshouses of substantially larger scales. His best known example is the Crystal Palace at the world's first International Exhibition in 1851. Elsewhere in Europe, Hector Horeau designed several conservatories of glass and iron, such as the Lyons Conservatory in France of 1847. In Germany, August von Voit designed the Great Palm House in the Old Botanical Gardens in Munich in 1860.