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NUMBER CCXCVIL 

 For J A NUAR F ,1823. 



CONTAINING TWO ENGRAVINGS. 



1. Illustrative of Mr. Tredgold's Paper on the Flexure of Astronomical 



Instruments. 



2. Deueeroucq and Nichols' Apparatus for Madame Gervais' New 



Method of Fermentation. 



By ALEXANDER TILLOCH, LL.D. 



M.R.I.A. M.O.S. M.A.S. F.S.A. EDIK. AKD PERTH; CORRESPONDING MEMBER OP THE 

 ROTAL ACADEMY OP SCIENCES, MUNICH; AND OF THE ACADEMY OF SCIENCES, 

 LITEUATURE AND ARTS, LEGHORN, ETC. 



And RICHARD TAYLOR, F.L.S. 



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