11 CONTENTS. 



Page 



XV. Notice of Two Earthquakes felt at Sea, ... 267 



XVI. Abstract of a Memoir on the Birds in the Environs of Geneva, by L. A. 

 Necker. With Observations, by a Correspondent, - . 269 



XVII. Account of the Discovery of an Inhabited Island in the Pacific. By 

 Captain Eeg of the Pollux Sloop of War, in the Service of his Majesty 

 the King of the Netherlands. In a Letter to Dr Brewster from G. 

 Moll, Professor of Natural Philosophy in the University of Utrecht, 278 



XVIII. Notice respecting the Working and Polishing of Granite in India. In 



a Letter to the Editor from Alexander Kennedy, M.D. F. R. S. E. 281 



XIX. Observations on the Superiority of Achromatic Telescopes with Fluid 

 Object-Glasses, as constructed by Dr Blair, - . 282 



XX. On Epistilbite, a New Mineral Species of the Zeolite Family. By Dr 

 Gustavus Rose, Berlin. Communicated by the Author, . 285 



XXI. On the Horary Variations of the Barometer. By Baron Alexander 



de Humboldt, ..... . 290 



XXII. Notice regarding Professor Mitscherlich's Observations on the Dimor- 

 phism of Hydrous Sulphate of Zinc, and Hydrous Sulphate of Magne- 

 sia. By William Haidinger, Esq., F. R. S. E. Communicated by 



the Author, - - - - - -301 



XXIII. Observations on the Geography of the Burrampooter and the Sanpoo 

 Rivers. By Captain R. Lachlan, 17th Regiment. In a Letter to the 

 Editor, - - - - 302 



XXIV. On a Property of Light, exhibited in the Examination of small Lu- 

 minous Points by Telescopes. By Professor Amici of Modena, 306 



XXV. Observations on the Relative Performances of Achromatic and Re- 

 fleeting Telescopes. By Mr Hehschel, Mr South, and Professor 

 Amici, ._---. 309 



XXVI. Farther Observations on Levyne, a New Mineral Species. By the 

 Editor, ..... 316 



XXVII. On the Torpidity of the Tortoise and Dormouse. By John Mur- 

 ray, Esq. F. S. A. F. L. S., &c. &c. - - - 317 



XXVIII. Observations on the Intensity of Magnetism in different parts of 

 the Earth's Surface. By Christian Hansteen, Professor of Astro- 

 nomy in the University of Norway. ... 323 



XXIX. On the Magnetising Power of the more refrangible rays of Light. 



By Mrs Mary Somerville, .... 328 



XXX. HISTORY OF MECHANICAL INVENTIONS AND PRO- 



CESSES IN THE USEFUL ARTS, - . 338 



1. Description of a simple Punt- Boat for saving time and labour. By 

 Andrew Waddell, Esq. F. R. S. E. Communicated by the Au- 

 thor, ..... - - ib. 



2. Method of condensing wood and giving it a closeness of grain for re- 

 sisting moisture, for the construction of furniture and other purposes. 



By Mr James Falconer Astlie, ... 333 



3. Discovery of a Fine Sand for Flint Glass at Alloa, superior to that 

 from Lynn Regis. By Robert Bald, Esq. F. R. S. E. Civil Engi- 

 neer. ....... ib. 



