THE 



PHILOSOPHICAL MAGAZINE 



COMPREHENDING 



THE VARIOUS BRANCHES OF SCIENCE, 



THE LIBERAL AND FINE ARTS, 



AGRICULTURE, MANUFACTURES, 



AND 



COMMERCE. 



BY ALEXANDER TILLOCH, 



HONORARY MEMBER OF THE KOYAL IRISH ACADEMY, &C. ScC. &C 



" Ni'c aranearum sar.e textus ideo melior quia ex se fila p;i;!fnunt, nee nostcr 

 villor quia ex alicnis libamus ut ajx-s." Just. Lii-s. Mo/iil. J-'olit. lib. i. c;)}) i. 



VOL. XXVITI. 

 for JUNE, JULY, AUGUST, and SEPrEMBEll, 1807. 





LONDON.- Xi-y'/T'C-^^-y, 



PRINTED FOR JOHN MURRAV, FLEET S'Mjf.BX, frA'*'^ 



A. CON.STABLR AND CO. EDINBURGH : 



And sold by Riciiakd;:on j'Cadei.l and Davie;;; LoNi;man, Hurst, 



Reks, and Giime; Symonds; Veknor, Hood, .and SiiARih ; 



Harding; HimiLtr ; London: Bki.l and Bkaui-'l i e, 



Edinburj^h: Brash & Run, and U. Niv kn, filasgow: 



and (Jii.Bi.K] and Houoks, Dublin. 



