Once the universal legend Leonardo Da Vinci invented a bridge without mortar. The lopsided stones in this model are wedged together in a similar manner to construct a wall. This “wall game” promotes a sense of balance and static, as well as dexterity and patience. Additionally, the different types of wood give players a feeling for natural materials. One cotton bag contains about 40 of these uneven stones with which little master builders can become the real Da Vinci.