These are one of the many kinds of traditional wooden Christmas decoration that are produced in the Erzgebirge region of Saxony. The area was historically full of silver and tin mines, and when these mines ran out the impoverished miners turned to wooden toy manufacture to get by. Many of the miners would have been familiar with quite complex wooden machinery, constructed for ore processing, pumping water and fresh air, etc, which was often water or animal-powered, and so it's quite common to find that the toys and decorations have mechanical elements - such as the 'pyramid' below which has elements which turn, powered by a draft created by lit candles.