Later that year, he created two additional automata, "The Tambourine Player" and "The Digesting Duck", which is considered his masterpiece. The duck had over 400 moving parts in each wing alone, and could flap its wings, drink water, seemingly digest grain, and seemingly defecate. Although Vaucanson's duck supposedly demonstrated digestion accurately, his duck actually contained a hidden compartment of "digested food", so that what the duck defecated was not the same as what it ate; the duck would eat a mixture of water and seed and excrete a mixture of bread crumbs and green dye that appeared to the onlooker indistinguishable from real excrement. Although such frauds were sometimes controversial, they were common enough because such scientific demonstrations needed to entertain the wealthy and powerful to attract their patronage. Vaucanson is credited as having invented the world's first flexible rubber tube while in the process of building the duck's intestines. Despite the revolutionary nature of his automata, he is said to have tired quickly of his creations and sold them in 1743.