more complex mechanical and optics-based toys were also invented. carpenter and westley began to mass-produce the kaleidoscope, invented by sir david brewster in 1817, and had sold over 200,000 items within three months in london and paris. the company was also able to mass-produce magic lanterns for use in phantasmagoria and galanty shows, by developing a method of mass production using a copper plate printing process. popular imagery on the lanterns included royalty, flora and fauna, and geographical/man-made structures from around the world. the modern zoetrope was invented in 1833 by british mathematician william george horner and was popularized in the 1860s. wood and porcelain dolls in miniature doll houses were popular with middle-class girls, while boys played with marbles and toy trains.