From Todd Veldhuizen:
Babbage never succeeded in having his analytical engine finished. However, a father-and-son pair of Swedes, Georg and Edvard Scheutz, succeeded in building a working difference engine in 1843. It was clear that the drive toward computer miniaturization had already begun: Babbage's design was intended to be driven by a steam engine, but the Scheutzes' "...does not require great power, and the machine could be kept in motion by a little dog, of the kind that is used in England as motive power for roasting-spits."
The mind, it boggles...
Source: M. Lindgren. Glory and failure: the difference engines of Johann M�ller, Charles Babbage and Georg and Edvard Scheutz. Stockholm papers in history and philosophy of technology 2017, Dept. of Technology and Social Change, Link�ping University, Link�ping, Sweden, 1987.