"No useless discourse. All conversation which does not serve to enlighten ourselves or others, to interest the heart or amuse the mind, is hurtful."
Nicolas Léonard Sadi Carnot was a French military engineer and physicist. A graduate of the École polytechnique, Carnot served as an officer in the Engineering Arm of the French Army. He also pursued scientific studies, and in June 1824 published an essay titled Reflections on the Motive Power of Fire. In that book, which would be his only publication, Carnot developed the first successful theory
"To take away to-day from England her steam-engines would be to take away at the same time her coal and iron. It would be to dry up all her sources of wealth, to ruin all on which her prosperity depends, in short, to annihilate that colossal power."
"Notwithstanding the work of all kinds done by steam-engines... their theory is very little understood, and the attempts to improve them are still directed almost by chance."
"Iron and heat are... the supporters, the bases, of the mechanic arts."
"Steam navigation... tends to unite the nations of the earth as inhahitants of one country. ...is not this the same as greatly to shorten distances?"
"There is almost as great a distance between the first apparatus in which the expansive force of steam was displayed and the existing machine, as between the first raft that man ever made and the modern vessel."
"Nature, in providing us with combustibles on all sides, has given us the power to produce, at all times and in all places, heat and the impelling power which is the result of it. To develop this power, to appropriate it to our uses, is the object of heat-engines."