Maine, Henry (1822–1888), English student of common law, ancient and modern, and the author of a remarkable work on the early village community. Chief works: "Village Communities in the East and West," and "Lectures on the Early History of Institutions.”
Marx, Karl (1818–1883), founder of the Social Democratic school of Socialism. Having left Germany as a political refugee, settled first in Paris, where he published, with Ruge, a Radical paper in German. Expelled from France in 1844, and from Belgium in 1848, he settled in London, where he was, in 1864, one of the chief founders of the International Working Men’s Association, and the intellectual leader of the General Council of the Association. Chief works: "The Misery of Philosophy" (1847)—a reply to Proudhon's "Philosophy of Misery" ("Economical Contradictions"); "Communist Manifesto" (1848), (about its origin, see W. Tcherkesoff's "Pages of Socialist History," 1896, and Professor Andler's "Historical Introduction" to it, in French, 1901); and especially his principal work, "Capital," of which the first (chief) volume appeared in 1867, containing a remarkable analysis of the genesis of capital, and became the foundation of the economical ideas of Social Democracy. Two more volumes of "Capital"—the last being a posthumous work—appeared later on.
Maurer, Georg Ludwig (1796–1872), a German historian, who has put on a scientific basis the study of the old village community. Chief work: "Einleitung zur Geschichte der Mark-, Hof-, Dorf-fund Stadt-Verfassung."
Mechanical Theory of Heat, one of the greatest acquisitions of modern science. It consists in its being now proved that all the phenomena winch we describe as heat phenomena (the heating of a body, its cooling, its melting, its boiling, the transformation of a liquid into a gaseous state, etc.) are the results of vibrations of the molecules of physical bodies. When the sum of these vibrational movements (invisible to the eye) which are going on in, let us say, a piece of iron, increases, the temperature of that piece of iron increases also. And vice versâ. Heat is thus a mood of motion. This is why we can produce heat by friction. The mass-movement of a train which is brought to a state of rest by powerful brakes, is spent in the friction of the wheels of the train upon the rails, and there it appears as heat in the heated rails and as sparks thrown from under the wheels. The quantity of mechanical force which is required to heat one pound of water by so many degrees can be measured; it has been measured with great accuracy; and this quantity is known as "the mechanical equivalent of heat." The mechanical theory of heat was foreseen, and even partly expressed, in the eighteenth century. Later on, in the "twenties" of the nineteenth century, it was expressed by Séguin senior, who had already made the necessary measurements. Rudolf Meyer, a German doctor, was the first to formulate it, in 1845, in a comprehensible and correct form; but he was not listened to.