»l. 64 



No. 318. 



Published the Last Day of every Month. — Price 2s. 6d, 



NUMBER CCCXVIII. 

 For OCTOBER 1824. 



WITH A PLATE 

 Illustrative of Mr. Sturgeon's Electro-Magnetic Rotating Ap- 

 paratus ; and of Mr. Haycraft's Apparatus for ascertaining 

 the Specific Heat of Gases. 



By ALEXANDER TILLOCH, LL.D. 



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LITERATURE AND ARTS, LEGHORN, ETC. 



And RICHARD TAYLOR, F.L.S. 



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 GICAL SOCIETY; AND OP THE ROYAL ASIATIC SOCIETY 



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