Part 1

SADI CARNOT

AT THE AGE OF 17.

(From a Portrait by Bailly, 1813.) ]

REFLECTIONS ON THE MOTIVE POWER OF HEAT.

FROM THE ORIGINAL FRENCH OF N.-L.-S. CARNOT, Graduate of the Polytechnic School.

ACCOMPANIED BY AN ACCOUNT OF CARNOT’S THEORY. BY SIR WILLIAM THOMSON (LORD KELVIN).

EDITED BY

R. H. THURSTON, M.A., LL.D., DR.ENG’G; Director of Sibley College, Cornell University; “Officier de l’Instruction Publique de France,” etc., etc., etc.

SECOND, REVISED, EDITION. FIRST THOUSAND.

NEW YORK: JOHN WILEY & SONS. LONDON: CHAPMAN & HALL, LIMITED. 1897.

Copyright, 1890, ROBERT H. THURSTON.

ROBERT DRUMMOND, ELECTROTYPER AND PRINTER, NEW YORK.

DEDICATED

=Sadi Carnot,=

PRESIDENT OF THE FRENCH REPUBLIC,

THAT DISTINGUISHED MEMBER OF THE PROFESSION OF ENGINEERING WHOSE WHOLE LIFE HAS BEEN AN HONOR TO HIS PROFESSION AND TO HIS COUNTRY;

AND WHO, ELEVATED TO THE HIGHEST OFFICE WITHIN THE GIFT OF THE

FRENCH NATION,

HAS PROVEN BY THE QUIET DIGNITY AND THE EFFICIENCY WITH WHICH HE HAS PERFORMED HIS AUGUST DUTIES THAT HE IS A WORTHY MEMBER OF A NOBLE FAMILY, ALREADY RENDERED FAMOUS BY AN EARLIER SADI CARNOT, NOW IMMORTAL IN THE ANNALS OF SCIENCE, AND IS HIMSELF DESERVING OF ENROLMENT IN A LIST OF GREAT MEN WHICH INCLUDES THAT OTHER DISTINGUISHED ENGINEER, OUR OWN FIRST PRESIDENT,

GEORGE WASHINGTON.

CONTENTS.

I. PAGE THE WORK OF N.-L.-SADI CARNOT. By the Editor, 1

II. THE LIFE OF N.-L.-SADI CARNOT. By Mons. H. Carnot, 20

III. REFLECTIONS ON THE MOTIVE POWER OF HEAT AND ON MACHINES FITTED TO DEVELOP THAT POWER. By Mons. N.-L.-Sadi Carnot, 37

IV. ACCOUNT OF CARNOT’S THEORY. By Sir William Thomson (Lord Kelvin), 127

APPENDIX. A. EXTRACTS FROM UNPUBLISHED WRITINGS OF CARNOT, 205 B. CARNOT’S FOOT-NOTES, 237 C. NOTE BY THE EDITOR, 261

PUBLISHERS’ NOTE.

The raison d’être of the following translation of the famous work of Carnot is not the usual one, either with the Publishers or the Editor—expectation of gain in either purse or fame. Neither could reasonably be anticipated from the reproduction of the work of an author of more than a half-century ago, in a field then unrecognized, and to-day familiar to but few; and especially when, as is in this case the fact, the work itself has been long out of date as a scientific authority, even had it ever held such a position. It could not be presumed that a very large proportion of even the men of science of the English-speaking world would be sufficiently familiar with the subject, or interested in its origin, to purchase such a relic of a primitive period as is this little book. Nor could the translation of the work, or the gathering together by the Editor of related matter, be supposed likely to be productive of any form of compensation. The hook is published as matter of limited but most intense scientific interest, and on that score only.