1 CONTENTS. 



Page 

 their External Form remains the same. By William Haidinger, 

 Esq. F. R. S. Edin. - 275 



XIV. Observations on the Barometer and Thermometer made at Mal- 

 manger and Ullensvang in Norway, during a period of thirty years, 

 from 1798 to 1828. By Provost Hertzberg of Ullensvang. 

 Communicated by the Author. - - 292 



XV. On the Employment of Equations of Condition in Naval Architec- 

 ture. By George Harvey, Esq. F. R. S. Lond. and Edin. F. L. S. 

 Honorary Member of the Society for promoting the Useful Arts of 

 Scotland, &c. &c. Communicated by the Author. - 294 



XVI. On the Cultivation of the Science of Shipbuilding. By George 

 Harvey, Esq. F.R.S. Lond. and Edin. Member of the Royal Geo- 

 logical Society of Cornwall, &c. &c. Communicated by the Author. 298 

 XVII. Remarks on Self-Registering Thermometers, particularly on Mr 



King's, described in last Number. Communicated by the Author, 300 

 XVIII. Description of Pyrolusite, or Prismatic Manganese Ore. By Wil- 

 liam Haidinger, Esq. F. R. S. E. - - 304 

 XIX. Comparison of the Hourly Mean Temperature at Christiania and 

 Leith in February and July. By Professor Hansteen. Commu- 

 nicated by the Author. - 309 

 XX. On a New Cleavage in Calcareous Spar, with a Notice of a Method 

 of detecting Secondary Cleavages in Minerals. By David Brew- 

 ster, LL.D. F. R.S. Lond. and Sec. R. S. Edin. - 311 

 XXI. On the Cause of the extraordinary figure of Calcareous Spar, and on its 



Cleavage in three different directions. By Christian Huygens, 314 

 XXII. New Researches on Endosmose and Exosmose. By M. Dutrochet, 317 



XX III. Observations on the Colour of Water, and on the Tints of the Ocean. 



iJy Sir Humphry Davy, Bart. - 324 



XXIV. ZOOLOGICAL COLLECTIONS, - - 327 



1. On the Natural History of the Par, - - ib. 



2. On the Generation and Migration of Eels, - - 328 



3. On the Luminous Appearance of the Ocean. By Lieut. R. 1n- 

 galls, - - - - - 330 



4. Circumstances relative to the Economy of Bees. By T. A. Kntght, 

 Esq. ----- 331 



XXV. HISTORY OF MECHANICAL INVENTIONS AND OF PRO- 

 CESSES AND MATERIALS USED IN THE FINE AND USE- 

 FUL ARTS, .... - 332 



1. Description of the Winch Bridge, the oldest Suspension Bridge in 

 England. Communicated by W. C. Trevelyan, Esq. ib. 



2. On Lithochromy, or the Art of multiplying Oil Coloured Litho- 

 graphic Paintings, .... 333 



3. On the Grass Oil of Nemaur. By J. Forsyth, Esq. ib. 



4. Theory of Sir H. Davy's Safety Lamp. By G. Libri, 334 



5. Protection against Damp, Rust, &c By John Murray, F. S. A. 



F. L. S. &c. Communicated by the Author, - 335. 



fJ. Improvement of Candles. By John Murray, F. L. S. and Lecturer 

 on Chemistry. Communicated by the Author, - 336 



