THE 

 LONDON, EDINBURGH, and DUBLIN j^^^ 



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. 

 RICHARD PHILLIPS, F.R.S.L.&E. F.G.S. &c. 

 SIR ROBERT KANE, M.D. M.R.I. A. 

 WILLIAM FRANCIS, Ph.D. F.L.S. F.C.S. 



v^Kt^ 



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

 vilior quia ex alienislibamus ut apes." Just. Lips. Po/iMib. i. cap. 1 . Not, 



VOL. I.— FOURTH SERIES. 



JANUARY— JUNE, 1851. 



LONDON. 



RICHAIID TAYLOR, RED LION COURT, FLEET STREET, 

 Printer and Publisher to the University of London; 



SOLD BY LONGM.\N, BROWN, GREEN, AND LONGMANS J SIMPKIN, MARSHALL 



AND CO.; s. highley; whittaKeii and co.; and sherwood, 



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