OF

JAMES WATT

BY

M. ARAGO

PERPETUAL SECRETARY TO THE ACADEMY OF SCIENCES.

TRANSLATED FROM THE FRENCH

WITH ADDITIONAL NOTES AND AN APPENDIX

BY JAMES PATRICK MUIRHEAD, ESQ. M. A.

OF BALLIOL COLLEGE OXFORD

ADVOCATE.

LONDON: JOHN MURRAY.

EDINBURGH: WILLIAM BLACKWOOD AND SONS.

M.DCCC.XXXIX.

615.

PREFACE.

IN 1699, Louis XIV. gave to the Academy of Sciences a new code of laws, by which several important changes were introduced into the constitution of that Society.

Of these, one of the most novel, was the admission of Foreign Associates. These were never to exceed eight in number, and were to be chosen without regard to any other considerations than their scientific fame, and the integrity of their lives. Hence, the honour of being admitted into that very distinguished class, has always been esteemed a reward of the most eminent philosophical attainments; and "the list of Foreign Associates," says Cuvier, "commencing with the names of Newton, Leibnitz, and Peter the Great, has never degenerated from its original splendour."*

In 1814, the name of JAMES WATT was added to this illustrious catalogue; and, some years after

his death, the duty of preparing an Historical Eloge, or biographical memoir, in which his scientific career, and the sense which his fellow-members entertained of his loss, should be recorded, devolved upon the Perpetual Secretary, M. Arago. That Eloge was read at the public meeting of the Academy of Sciences, on the 8th of December, 1834.

If the title of this work requires any further explanation, it may be given in the words of Fontenelle, who, more than a century ago, filled the same office which M. Arago now holds, and published the Eloges of many Academicians. "The title of Eloges," says he, "is not quite so correct as that of Lives would be; for they are, strictly speaking, merely Lives, such as would be written by an author who only did justice to their subjects."

The well-known abilities of M. Arago, himself a distinguished cultivator of the same sciences as the great philosopher whom he here commemorates, have been exercised with even more than their usual success, on the congenial topic thus presented to him. He has explained many most important inventions, involving numerous and minute scientific details, with so much simplicity and precision, as to render them intelligible, and therefore interesting, to every reader; while his peculiar felicity of illustration and powers of