John Cadbury opened a grocers shop in Birmingham in 1824 and began making chocolate. In 1831 he started manufacturing cocoa and chocolate on a commercial scale. Cadbury's moved to a bigger factory in Birmingham in 1847. George and Richard Cadbury took over the company from their father in 1861 and found a Dutch process to improve their cocoa. They built houses for workers in Bournville, outside Birmingham, starting in 1879 to improve conditions. Cadbury launched their first milk chocolate bar in 1897 and their iconic Dairy Milk bar in 1905.