THE

EDINBURGH NEW

2929 2-16

PHILOSOPHICAL JOURNAL.

THE

EDINBURGH NEW

PHILOSOPHICAL JOURNAL,

EXHIBITING A VIEW OF THE

PROGRESSIVE DISCOVERIES AND IMPROVEMENTS

IN THE

SCIENCES AND THE ARTS.

EDITORS.

THOMAS ANDERSON, M.D., F.R.S.E.,

REGIUS PROFESSOR OF CHEMISTRY, UNIVERSITY OF GLASGOW;

SIR WILLIAM JARDINE, BART., F.R.SS.L. AND E.;
JOHN HUTTON BALFOUR, A.M., M.D.,

F.R.S., SEC. R.S. EDIN., F.L.S.,

REGIUS KEEPER OF THE ROYAL BOTANIC GARDEN, AND PROFESSOR OF MEDICINE AND BOTANY,
UNIVERSITY OF EDINBURGH.

FOR AMERICA,

HENRY D. ROGERS, LL.D., Hon. F.R.S.E., F.G.S.,

STATE GEOLOGIST, PENNSYLVANIA; PROFESSOR OF NATURAL HISTORY IN THE
UNIVERSITY OF GLASGOW.

EDINBURGH:

ADAM AND CHARLES BLACK.

LONGMAN, BROWN, GREEN, & LONGMANS, LONDON.
MDCCCLXIII.