Vol. 56. 



November 1820. 



No. 271- 



'^£^^^ 



^i^ Published the Last Day of every Month, 



yM [PRICE 2s. 6J.] 



iS "^^^^ I4r 



W PHILOSOPHICAL MAGAZINE^ 



AiND JOURNAL: 



CON3PKEHJEMDINO 



THE VARIOUS BRANCHES OF SCIENCE, 



THE LIBERAL AND FINE ARTS, 



GEOLOGY, 



AGRICULTURE, 



MANUFACTURES AND COMMERCE. 



i NUMBER CCLXXI. 



H For NOVEMBER 1820. 



v^ WITH A PLATE BY PORTEfl 



"^\ Exhibiting Sections, &c. of Mr. Malam's Improved Gas-Meter. ^Ji| 



A BY ALEXANDER TILLOCH, 



I 



M.U.I.A. M.G.S. M.R.A.S. JIUXK.'II, F.S.A. EDIN. AND PERTH, 

 M.S.E.l.N. OF FRANCE, &C. c^C. &C. 



LONDON: 



PRfNTED BY RICHAjlD AND ARTHUR TAYLOR, SHOE-LANE '. 



And sold by Cadell and Davies ; Longman, Hurst, Rees, fc^y 

 Or ME, & Brown; Highlky; Sherwood and Co. ; Harding im^if: 

 Underwood; SiMPKiNandMARsnALL ; London: Constable t >^ 

 and Co. Ediiiburgli: Brash and RriD; Duncan; and Pen- >Ji4^ 



an, Glasgow: and Gilbert and Hodges, Dublin. 



^ 



