The mathematician of to-day admits that he can neither square the circle, duplicate the cube or trisect the angle. May not our mechanicians, in like manner, be ultimately forced to admit that aerial flight is one of that great class of problems with which men can never cope... I do not claim that this is a necessary conclusion from any past experience. But I do think that success must await progress of a different kind from that of invention.

The demonstration that no possible combination of known substances, known forms of machinery and known forms of force, can be united in a practical machine by which men shall fly along distances through the air, seems to the writer as complete as it is possible for the demonstration to be.

One of the most beautiful hypotheses ever propounded in physics is ... the Dynamical Theory of Gases

My first undertaking in the way of scientific experiment was in the field of economics and psychology.

Though born in Nova Scotia, I am of almost pure New England descent.

My father was the most rational and the most dispassionate of men.

As years passed away I have formed the habit of looking back upon that former self as upon another person, the remembrance of whose emotions has been a solace in adversity and added zest to the enjoyment of prosperity.