viii CONTENTS. 



SUPPLEMENT TO VOL. XVII. 



Engravings of the following Objects: 1. Apparatus for triturating Quicksilvef: 

 2. Erman's New Classes of Galvanic Conductors: 3. Mr. J. Trotter/s Curvili- 

 near Saw; 4. Mr. J. Hardie's Bookbinder's Cutting Press. 



I. Description of a Machine for triturating and combining Quicksilver with other 

 Substances. By a Correspondent - - - 313 



II. A Memoir on Two new Classes of Galvanic Conductors. By Mr. Erman 



3i.a 



III. Inquiries concerning the Oxidations of Iron. By Mr. Darso 328 



IV. Description of a Curvilinear Saw, invented by John Trotter, Esq., of Soho 

 Square - 334 



V. Account of a Bookbinder's Cutting Press, for wliich Fifteen Guineas were 

 yoted to Mi"- James Hardie, of Glasgow, by the Society of Arts 336 



VI. On Blende, and some other Articles. By Professor Proust - 337 



VIL Remarks on the Structure of Mount Jura, from a considerable Number of 

 Heights taken by the Barometer, and extended through France to the Sea. 

 By Mr. And. de Gy, Member of the Academy of Cassel, &c. 341 



VIIL Some Mineralogical and Geological Observations, made in the Isle qf 

 Arran. By the Rev. James- Headrick ... 344 



IX. Questiqns respecting the Vines and Wines of Champagne, by Mr. ChaptaJ, 

 with Answers to them by Mr. Gernon, of Epernay - , 353 



3L On the most sensible Reagents for Muriatic, Carbonic, and Sulphuric Acids, 

 and for Ammonia. By C. H. PfarT, Professor of Chemistry at Kiel. 3b'0 



XI. Some farther Remarks on the pretended Formation of Muriatic Acid in 

 Water by the Influence of the Galvanic Pile. By the same - 362 



XII. Description of the Mode of making Threshing-FIoors in the Commune of 

 Valbonnais, in the Department of the Isere. By Mr. J. J. Champollion Figeac, 

 Secretary to the Society of Sciences and Arts at Grenoble, &c. 363 



XIII. Scientific Newsr— French National Institute - - 365 



