"We learn much by tribulation, and by adversity our hearts are made better."

"The desire for flight is the expression of a deep-seated human instinct."

"If its engine stops, it must fall with deathly violence, for it can neither glide like the aeroplane or float like the balloon. The helicopter is much easier to design than the aeroplane, but is worth…"

"The fact that the machine did not fall apart at the first gust of wind was a great encouragement."

"The flying machine which will really fly might be evolved by the combined and continuous efforts of mathematicians and mechanicians in from one million to ten million years — provided, of course, we c…"