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

The beginning of 1856 found me teaching in the family of a planter named Bryan, residing in Prince George County, Md., some fifteen or twenty miles from Washington.

A few years later the Naval Academy was founded at Annapolis, and a similar course was pursued to provide it with a corps of instructors.

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

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.

Quite likely the twentieth century is destined to see the natural forces which will enable us to fly from continent to continent with a speed far exceeding that of a bird.

Whenever a total eclipse of the sun was visible in an accessible region parties were sent out to observe it.