Singing bird automaton - Germany - 1910-1920, 1920-1930

The singing bird slot machine comes from my parents' estate.
The case/base and cage are made of brass. The movement is housed in the case/base, and the winding mechanism as well as the locking mechanism are located on the underside.
The bird in the cage, with feather adornments, moves its beak and tail feathers to the bird chirping – see video –.
To the best of my knowledge, the manufacturer is the company Karl Griesbaum from the Black Forest.
Manufactured around 1910/1920. Unfortunately, many Griesbaum bird-playing automata lacked markings both inside and outside, as was the case here as well.

The total height of the slot machine is 25 cm, the diameter of the lower body is 15.5 cm, and the diameter of the cage is 10 cm.