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THE 



PHILOSOPHICAL MAGAZINE 

 AND JOURNAL: 



COMPKEHBNDINO 



THE VARIOUS BRANCHES OF SCIENCE, 

 THE LIBERAL AND FINE ARTS, 

 GEOLOGY, 

 AGRICULTURE, 



MANUFACTURES AND COMMERCE. 



NUMBER CCLXIX. 

 Far SEPTEMBER 1820. 



WITH A PLATE BY PORTER 



Illustrative of Mr. Hall's Percussion Gun-Lock; and of 

 Mr. Park's Moorir 



BY ALEXANDER ULLOCH, 



M.ll.I.A. M.O.S. M.n.A.S. MUNICH, F.8.i^g|l)IN . ANl>rERTlI, 

 M.S.&.I.N. OF FRAtJCE, &C.'jA &C. 



V^-OR, SHO 



E-LANE 



LONDON: 



PRINTED BY RICHARD AND ARTHUR TAV" 



, And sold by CADELLand Davies; LoNOf an, Hurst, Rees, 



■ Orme, & Brown ; Highley;Sherv/ood -ndCo.; Harding ; 



Underwood; SiMPKiNandMARSHAtL;I:ondon: Constable' 



and Co. Edinburgh: Brash and Reid i'DuNCAN; and 1 f.n- 



MAN, Glasgow: and Gilbert and H(>'>GEs^)ublii-i. 



