The Second Law of Thermodynamics: Memoirs by Carnot, Clausius, and ThomsonReflections on the motive power of heat by Sadi Carnot -- On the motive power of heat and on the laws which can be deduced from it for the theory of heat, by R. Clausius -- The dynamical theory of heat. -- By W. Thomson (Lord Kelvin). |
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100 degrees analytical expression assumed atmospheric air ature Briggsian logarithms calculated carbonic acid Carnot's theory change of temperature change of volume Clapeyron Clausius column compression conclusions condensation condition consequently considered constant pressure constant temperature constant volume corresponding cylinder deduced demonstration denote descent of caloric determined dp dt dynamical theory elastic fluid equation exactly expansion experimental experiments expression external former paper formula function gaseous laws Gay-Lussac Gay-Lussac's law hypothesis increase infinitely small Joule Joule's kilogram latent heat liquid magnitude maximum density mechanical effect mechanical equivalent motive power produced numbers obtain operations perature permanent gases piston power of heat principle quantity of heat quantity of motive quantity of vapor raise ratio refrigerator Regnault result saturated steam specific heat steam-engine substance suppose tempera theoretical theory of heat thermal tion total heat transfer ture unit of heat vis viva water vapor weight zero
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Page 116 - It is impossible, by means of inanimate material agency, to derive mechanical effect from any portion of matter by cooling it below the temperature of the coldest of the surrounding objects*.
Page 113 - The object of the present paper is threefold : — (1) To show what modifications of the conclusions arrived at by Carnot, and by others who have followed his peculiar mode of reasoning regarding the motive power of heat, must be made when the hypothesis of the dynamical theory, contrary as it is to Carnot's fundamental hypothesis, is adopted. (2) To point out the significance in the dynamical theory, of the numerical results deduced from Regnault's observations on steam, and communicated about two...
Page 116 - If this axiom be denied for all temperatures, it would have to be admitted that a self-acting machine might be set to work and produce mechanical effect by cooling the sea or earth, with no limit but the total loss of heat from the earth and sea, or, in reality, from the whole material world.
Page 118 - It is impossible for a selfacting machine, unaided by any external agency to convey heat from one body to another at a higher temperature, or heat cannot of itself pass from a colder to a warmer body.
Page 10 - ... quantity by the compression of the elastic fluids. This preliminary idea being established, let us imagine an elastic fluid, atmospheric air for example, shut up in a cylindrical vessel, abed (Fig. 1), provided with a movable diaphragm or piston, cd. Let there be also two bodies, A and B, kept each at a constant temperature, that of A being higher than that of B.
Page 111 - To distinguish this motion from others, and to signify the cause of our sensation of heat," and of the expansion or expansive pressure produced in matter by heat, "the name repulsive motion has been adopted *." 2. The dynamical theory of heat, thus established by Sir Humphry Davy, is extended to radiant heat by the discovery of phenomena, especially those of the polarization of radiant heat, •which render it excessively probable that heat propagated through "vacant space," or through diathermanic...
Page 112 - I have lately proved experimentally that heat is evolved by the passage of water through narrow tubes. My apparatus consisted of a piston perforated by a number of small holes, working in a cylindrical glass jar containing about 7 Ib.
Page 132 - Water," by my elder brother, still hold. Also, we see that Carnot's expression for the mechanical effect derivable from a given quantity of heat by means of a perfect engine in which the range of temperatures is infinitely small, expresses truly the greatest effect which can possibly be obtained in the circumstances ; although it is in reality only an infinitely small fraction of the whole mechanical equivalent of the heat supplied ; the remainder being irrecoverably lost...
Page 115 - If an engine be such, that when it is worked backwards, the physical and mechanical agencies in every part of its motions are all reversed, it produces as much mechanical effect as can be produced by any thermodynamic engine, with the same temperatures of source and refrigerator, from a given quantity of heat.
Page 146 - This formula, established without any assumption admitting of doubt, expresses the relation between the heat developed by the compression of any substance whatever, and the mechanical work which is required to effect the compression, as far as it can be determined without hypothesis by purely theoretical considerations. 64. The preceding formula leads to that which I formerly gave for the case of fluids subject to the gaseous laws; since for such we have pv=Pov0(l+-Et) ....... (1), from which we...