Radierungen - Etchings
Etchings of animal images that were colored later to give a naturalistic representation of life seen

Solution

The seen etchings were done to give Children an impression about foreign or even well known animals. Beside the natural representation of familiar and strange animal groups the children lerned playfully, the numbers, eg 1 Lioness, 2 orangutans, 3 Elelephants, 4 penguins, 5 gazelles etc.