Reply To: Ballone Burini P-45
The André Borel and Phillippe Seiler patent for the Clavietta shows some good pictures of the mechanism, and explains how the airflow is directed.
Wind actuated musical instrument
US 3034392 A
https://www.google.com/patents/US3034392?dq=ininventor:%22Andre+Borel%22&hl=en&sa=X&ei=sPpeVeqwBZTe7Ab43oDABw&ved=0CCUQ6AEwAQ