OU3 



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. 

 SIR WILLIAM THOMSON, Knt. LL.D. F.R.S. &c. 



AND 



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



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

 ilior quia ex alienis libamus ut apes." Just. Lips. Polii. lib. i. cap. 1. Not. 



VOL. X.— FIFTH SERIES. 

 JULY— DECEMBER 1880. 



^ 



J DEC 14/880 



L X D .V : 

 TAYLOR AND FRANCIS, RED LION COl'KT, FLEET STREET. 



BOM) BY LONGMANS, GREEN, HEADER, AND DYER; KENT AND CO. J SIMPKIN, MAR8HALL 



AND CO. : AND WIIITTAKEIi. AND CO. ; AND BY ADAM AND CHARLES BLACK, 



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