U 



THE 

 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. 

 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. 



" Nee aranearum sane textus ideo melior quia ex se fila gignunt, nee noster 

 vilior quia ex alienis libamus ut apes." Just. Lips. Polit. lib. i. cap. 1 . Not. 



VOL. XXIX.— FOURTH SERIES. 



JANUARY— JUNE, 1865. 



tV» 



LONDON. 



TAYLOR AND FRANCIS, RED LION COURT, FLEET STREET, 



Printers and Publishers to the University of London ; 



SOLD BY LONGMAN, GREEN, LONGMAN, ROBERTS, AND GREEN ; SIKPKIN, 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. 



