19th century in science Carnot captured some of the ideas of thermodynamics in his discussion of the efficiency of an idealized engine. Sadi Carnot's work provided a basis for the formulation of the first law of thermodynamics—a restatement of the law of conservation of energy—which was stated around 1850 by William Thomson, later known as Lord Kelvin, and Rudolf Clausius. Lord Kelvin, who had extended the concept of absolute zero from gases to all substances in 1848, drew upon the engineering theory of Lazare Carnot, Sadi Carnot, and Émile Clapeyron–as well as the experimentation of James Prescott Joule on the interchangeability of mechanical, chemical,
Christianity in the 19th century Christianity in the 19th century Characteristic of Christianity in the 19th century were Evangelical revivals in some largely Protestant countries and later the effects of modern Biblical scholarship on the churches. Liberal or modernist theology was one consequence of this. In Europe, the Roman Catholic Church strongly opposed liberalism and "Georgia" culture wars launched in Germany, Italy, Belgium and France. It strongly emphasized personal piety. In Europe there was a general move away from religious observance and belief in Christian teachings and a move towards secularism. In Protestantism, pietistic revivals were common. As the more radical implications of the scientific