The following winter, Vaucanson added two more machines to the show. One was a second android musician, a life-size Provençal shepherd that played twenty minuets and other dance tunes on a pipe grasped in its left hand, while accompanying itself with its right on a drum slung over its shoulder. The pipe had only three holes, which meant that the notes were produced almost entirely by the player’s variations of blowing pressure and tongue stops. Working to reproduce these subtleties in his automaton, Vaucanson found that human pipers employed a much greater range of blowing pressures than they themselves realized. The Piper also yielded another surprising discovery. Vaucanson had assumed that each note would be the product of a given finger position combined with a particular blowing pressure, but he discovered that the blowing pressure for a given note depended upon the preceding note, so that, for example, it required more pressure to produce a D after an E than after a C, obliging him to have twice as many blowing pressures as notes. The higher overtones of the higher note resonate more strongly in the pipe than the lower overtones of the lower note; but pipers themselves were not aware of compensating for this effect, and the physics of overtones was explained only in the 1860s by Hermann von Helmholtz.