In famous publications, The Mechanical Theory of Heat (Die Mechanische Wärmetheorie) – with its Applications to the Steam Engine and to Physical Properties of Bodies is a 376-page 1867 book written by German physicist Rudolf Clausius, that is the founding publication and linchpin of the entire edifice of the science of thermodynamics. [1]

The book, a collection of nine memoirs (papers) of Clausius, is the result of a prolonged investigative correction of French physicist Sadi Carnot's 1824 paper "On the Motive Power of Fire", in which Clausius modified Carnot's caloric theory based postulates on the nature of the relationship between heat and work, in particular the assumption that no change occurs in the working body during one heat cycle, with the recent experimental discoveries contained in the theory of heat and mechanical equivalent of heat, to result in the modern mathematical formulation of the first and second laws of thermodynamics.

First edition - 1865:
The first edition of Clausius' The Mechanical Theory of Heat, consist of a mathematical introduction, his collection of nine memoirs on the mechanical theory of heat, published in the fifteen years prior in various journals (principally in Poggendorff’s Annalen), along with an attachment of notes and appendices:

• Mathematical Introduction (1858): On the Treatment of Differential Equations which are not Directly Integrable, pp. 1-13.
• First Memoir (1850): On the Moving Force of Heat and the Laws of Heat Which May be Deduced Therefrom, pp. 14-69
• Second Memoir (1851): On the Deportment of Vapour During its Expansion Under Different Circumstances, pp. 90-100
• Third Memoir (1851): On the Theoretic Connexion of Two Empirical Laws Relating to the Tensions and the Latent Heat of Different Vapours, pp. 104-110
• Fourth Memoir (1854): On a Modified Form of the Second Fundamental Theorem in the Mechanical Theory of Heat, pp. 111-135
• Fifth Memoir (1856): On the Application of the Mechanical theory of Heat to the Steam-Engine, pp. 136-207
• Sixth Memoir (1862): On the Application of the Theorem of the Equivalence of Transformations to Interior Work, pp. 215-250
• Seventh Memoir (1863): On an Axiom in the Mechanical Theory of Heat, pp. 267-289.
• Eighth Memoir (1863): On the Concentration of Rays of Heat and Light, and on the Limits of its Action, pp. 290-326.
• Ninth Memoir (1865): On Several Convenient Forms of the Fundamental Equations of the Mechanical Theory of Heat, pp. 327-365.

Second edition - 1875:
After having taught the subject for a number of years, in 1875 Clausius finished rewriting the book so as to take it from a collection of papers to a "text-book of the subject". It was published in 1876 and later as an English translation edition in 1879. [2] In the preface to the second edition, he states that his long experience as a lecturer on the subject at the Polytechnic School and at several universities over the last ten years, since the publication of the first edition, has taught him how the subject matter should be arranged to make this “somewhat difficult theory” more readily intelligible. The chapters to the second edition are listed below:

#	Chapter Title	Pgs.
	Translator's Preface (by Walter Browne)	v-vi
	Author's Preface (by Rudolf Clausius)	vii-viii
	Table of Contents	ix-xvi
	Mathematical Introduction: on Mechanical Work, On Energy, and on the Treatment of Non-Integrable Differential Equations	1-20
I	First Main Principle of the Mechanical Theory of Heat: or Principle of the Equivalence of Heat and Work	21-38
II	On Perfect Gases	39-68
III	Second Main Principle of the Mechanical Theory of Heat	69-90
IV	The Second Main Principle Under Another Form: or Principle of the Equivalence of Transformations	91-109
V	Formation of the Two Fundamental Equations	110-125
VI	Application of the Mechanical Theory of Heat to Saturated Vapour	126-162
VII	Fusion and Vaporization of Solid Bodies	163-174
VIII	On Homogeneous Bodies	175-194
IX	Determination of Energy and Entropy	195-211
X	On Non-Reversible Processes	212-234
XI	Application of the Mechanical Theory of Heat to the Steam-Engine	235-294
XIII	On the Concentration of Rays of Light and Heat on the Limits of its Operation	295-331
XIII	Discussions on the Mechanical Theory of Heat as Here Developed, and on its Foundations	332-362
	Appendix I: On the Thermo-Elastic Properties of Solids (by Walter Browne)	363-368
	Appendix II: On the Continuity of the Liquid and and Gaseous States of Matter (by Walter Browne)	369-371
	Appendix III: On Capillarity (by Walter Browne)	372-376

Overviews of the chapters are slowly being written as subfiled wikipages to this page (as linked to above).

	References 1. (a) Clausius, R. (1865). The Mechanical Theory of Heat – with its Applications to the Steam Engine and to Physical Properties of Bodies. London: John van Voorst, 1 Paternoster Row. MDCCCLXVII. (b) The Mechanical Theory of Heat (20 online synopsis pages) - HumanThermodynamics.com. 2. Clausius, Rudolf. (1879). The Mechanical Theory of Heat, (2nd ed). London: Macmillan & Co.
Note on the new inprint availability of Clausius' The Mechanical Theory of Heat by American chemical engineer Libb Thims (Oct 2008, 4:11-min)