An admirable aeronautical engineer, who is known from his creation of the first helicopter.
In the book you can read however that this was only attained after a succesful life as an aeroplane builder.
At a later age he decided to do something copletely different and that is what became the helicopter.
I am in the posession of an autographed copy, which was obtained in a small bookshop in Maastricht. If somebody could tell me how it got there......