The London, Edinburgh and Dublin Philosophical Magazine and Journal of Science

LONDON, EDINBURGH, AND DUBLIN

PHILOSOPHICAL MAGAZINE

AND

JOURNAL OF SCIENCE.

CONDUCTED BY

SIR DAVID BREWSTER, K.H. LL.D. F.R.S.L. & E. &c.
RICHARD TAYLOR, F.L.S. G.S. Astr. S. Nat. H. Mosc. &c.
SIR ROBERT KANE, M.D., F.R.S., M.R.I.A.

WILLIAM FRANCIS, PH.D. F.L.S. F.R.A.S. F.C.S.
JOHN TYNDALL, F.R.S. &c.

"Nec aranearum sane textus ideo melior quia ex se fila gignunt, nec noster
vilior quia ex alienis libamus ut apes." JUST. LIPS. Polit. lib. i. cap. 1. Not.

VOL. XIII.-FOURTH SERIES.

JANUARY-JUNE, 1857.

LONDON.

TAYLOR AND FRANCIS, RED LION COURT, FLEET STREET,
Printers and Publishers to the University of London;

SOLD BY LONGMAN, BROWN, GREEN, LONGMANS, AND ROBERTS; SIMPÉIN,
MARSHALL AND CO.; WHITTAKER AND CO.; AND PIPER AND CO.,
LONDON-BY ADAM AND CHARLES BLACK, AND THOMAS

CLARK, EDINBURGH; SMITH AND SON, GLASGOW;
HODGES AND SMITH, DUBLIN; AND
PUTNAM, NEW YORK.

"Meditationis est perscrutari occulta; contemplationis est admirari perspicua . . . . . Admiratio generat quæstionem, quæstio investigationem, investigatio inventionem."-Hugo de S. Victore.

-"Cur spirent venti, cur terra dehiscat,

Cur mare turgescat, pelago cur tantus amaror,
Cur caput obscura Phoebus ferrugine condat,
Quid toties diros cogat flagrare cometas;
Quid pariat nubes, veniant cur fulmina cœlo,
Quo micet igne Iris, superos quis conciat orbes

Tam vario motu."

J. B. Pinelli ad Mazonium.

TIRKYKA TET VWD ZIVVLOKD TIMOR

CONTENTS OF VOL. XIII.

(FOURTH SERIES.)

NUMBER LXXXIII.-JANUARY 1857.

Mr. G. Gore on the Development of Dynamic Electricity by

the Immersion of unequally Heated Metals in Liquids

Mr. A. Cayley's Supplementary Remarks on the Porism of the

In-and-circumscribed Triangle......

M. J. Bertrand on Foucault's Gyroscope.

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