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. XXVIL— FOURTH SERIES. 

 JANUARY— JUNE, 1864. 



rrmsoyv 



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 \ SIMPKIN, MARSHALL 



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