EXPERIMENTAL RESEARCHES

IN

CHEMISTRY AND PHYSICS.

BY

MICHAEL FARADAY, D.C.L., F.R.S.,

FULLERIAN PROFESSOR OF CHEMISTRY IN THE ROYAL INSTITUTION OF GREAT BRITAIN.
HON. MEM. R.S.ED., CAMB. PHIL., AND MED. CHIRURG. SOCC., F.G.S., Ord. BORUSSI POUR
LE MÉRITE" EQ., COMMANDER OF the Legion of HONOUR, INSTIT. IMP. (ACAD. SC.)
PARIS. SOCIUS, ACADD. IMP. SC. VINDOB. ET PETROP., REG. SC. BEROL.,
TAURIN., HOLM., MONAC., NEAPOL., AMSTELOD., BRUXELL., BONON., ITAL.

MUT., SOCC. REG. GOTTING., ET HAFN., UPSAL., HARLEM.

ACAD. AMER. BOST., ET SOC. AMER. PHILAD. SOCIUS, ACAD. PANORM., SOCC. GEORG.
FLORENT., ET PHILOM. PARIS., INSTIT. WASHINGTON., ET ACAD.
IMP. MED. PARIS. CORRESP., ETC.

REPRINTED FROM THE PHILOSOPHICAL TRANSACTIONS OF 1821-1857;
THE JOURNAL OF THE ROYAL INSTITUTION; THE PHILOSOPHICAL MAGAZINE,

AND OTHER PUBLICATIONS.

LONDON:

RICHARD TAYLOR AND WILLIAM FRANCIS,

PRINTERS AND PUBLISHERS TO THE UNIVERSITY OF LONDON,
RED LION COURT, FLEET STREET.

1859.

PREFACE.

THE reasons which induce me to gather together in this Volume the various physical and chemical papers scattered in the Philosophical Transactions and elsewhere, are the same as those which caused the 'Experimental Researches in Electricity' to be collected into one Series. As investigations, several of them are very imperfect; but it was thought a duty to print them just as they were, that they might be referred to as safely for facts, opinions, and dates, as the original papers. The correction of certain phrases and typographical errors, and the addition of some matter here and there with its proper date, is not considered as interfering with this intention.

October, 1858.

MICHAEL FARADAY.