THE 



PHILOSOPHICAL MAGAZINE, 



OR 



ANNALS 



OF 



CHEMISTRY, MATHEMATICS, ASTRONOMY, 



NATURAL HISTORY, AND 



GENERAL SCIENCE. 



BY 



RICHARD TAYLOR, F.S.A. L.S. G.S. M. Astr. S. &c. 



AND 



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



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

 vilior quia ex alienis libamus ut apes." JUST. LIPS. Monit. Polit. lib. i. cap. 1. 



VOL. IX. 



NEW AND UNITED SERIES OF THE PHILOSOPHICAL MAGAZINE 



AND ANNALS OF PHILOSOPHY. 



JANUARY-JUNE, 1831. 



LONDON: 



PRINTED BY RICHARD TAYLOR, RED LION COURT, FLEET STREET, 

 Printer to the University of London. 



SOLD BY LONGMAN, REES, ORME, BROWN, AND GREEN; CADELL ; BALDWIN 

 AND CRADOCK ; SHERWOOD, GILBERT, AND PIPER J SIMPKIN 



AND MARSHALL; UNDERWOOD; AND s. HIGHLEY, LONDON : , 



AND BY ADAM BLACK, EDINBURGH; SMITH AND SON, 

 GLASGOW J AND HODGES AND M'ARTHUR, DUBLIN. 



