*° Lg5 



THE ^ 



LONDON, EDINBURGH, and DUBLIN 



PHILOSOPHICAL MAGAZINE 



AND 



JOURNAL OF SCIENCE. 



CONDUCTED BY 



SIR ROBERT KANE, LL.D. F.R.S. M.R.I.A. F.C.S. 



AND 



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. XXXVI.— FOURTH SERIES. " 



JULY— DECEMBER 1868. 



■£■' . 



LONDON. 



TAYLOR AND FRANCIS, RED LION COURT, FLEET STREET, 



Printers and Publishers to the University of London j 



SOLD BY LONGMANS, GREEN, READER, AND DYER; SIMPKIN, MARSHALL AND CO. ', 



WHITTAKER AND CO.; AND KENT AND CO., LONDON: BY ADAM AND 



CHARLES BLACK, AND THOMAS CLARK, EDINBURGH ; 

 SMITH AND SON, GLASGOW; HODGES AND 

 SMITH, DUBLIN ; AND PUTNAM, 

 NEW YORK. 



