The final result of our researches has widened the class of substances sensitive to light vibrations, until we can propound the fact of such sensitiveness being a general property of all matter.

Before anything else, preparation is the key to success.

Neither the Army nor the Navy is of any protection, or very little protection, against aerial raids.

I begin my work at about nine or ten o'clock in the evening and continue until four or five in the morning. Night is a more quiet time to work. It aids thought.

Perseverance must have some practical end, or it does not avail the man possessing it. A person without a practical end in view becomes a crank or an idiot. Such persons fill our asylums.

I am a believer in unconscious cerebration. The brain is working all the time, though we do not know it. At night it follows up what we think in the daytime. When I have worked a long time on one thing, I make it a point to bring all the facts regarding it together before I retire; I have often been surprised at the results... We are thinking all the time; it is impossible not to think.