A pressed iron sheeting of regular undulations, known in the trade as 'S-profile galvanised sheet-metal'. It originated under patent to Henry R Palmer a civil engineer in London, in 1829. Richard Walker (to whom the patent had been attributed) acquired the patent and was in production and advertising the product by 1832. In 1837 a patent was taken out by HV Craufurd in 1837 and Sorel in the same year in France for hot-dipped galvanising, and the combination of these technologies into a single product is claimed by John Porter of Southwalk in 1843. (See Herbert, 1978: Chapter 3 'Corrugated iron and prefabrication').
The product was an immediate success in the colonies, and its use in South Africa ubiquitous in replacing thatch or tiles as a roof covering. In local South African parlance it became known as 'zinc', the metal component of the galvanising finish. In kit form (see Prefabricated wood-and-iron) it enabled the rapid housing of the mining towns of Kimberley and later Johannesburg. It is of the most widely used materials in creating shelter and informal housing. Its use today is still ubiquitous and its aesthetic as a material has seen contemporary resurgence as being fashionable.