441 



lution of numbers, ii. 2 ; explanation 

 of an optical deception in the ap- 

 pearance of the spokes of a wheel 

 seen through vertical apertures, ii. 

 230. 



Roots, on the origin and formation of, 

 i. 328 ; on the causes which influ- 

 ence the direction of the growth of, 

 i. 398. 



Ross (Lieut. J. C.), observations to de- 

 termine the amount of atmospherical 

 refraction at Port Bowen, ii. 296. 



Rotation, on the magnetism of iron 

 and other substances during, ii. 241, 

 243, 249, 251, 293, 295, 305 ; elec- 

 trical and magnetic, ii. 287. 



Rumford (Count) on a curious pheno- 

 menon observed on the glaciers of 

 Chamouny, with observations on the 

 propagation of heat in fluids, i. 133 ; 

 on the nature of heat, and the mode 

 of its communication, i. 139. 



Rumker (C.), calculations of some ob- 

 servations of the solar eclipse on 7th 

 Sept. 1820, ii. 150. 



Russell (Dr. P.) on the orifices found 

 in poisonous snakes, i. 138 ; on the 

 voluntary expansion of the skin of 

 the neck in the Cobra de Capello, or 

 hooded snake, i. 157. 



S. 



Sabine (Capt. E.) on irregularities in 

 the direction of the compass needles, 

 caused by the attraction of the iron 

 in ships, ii. 109 ; on the dip and va- 

 riation of the magnetic needle, ii. 

 110; experiments to determine the 

 acceleration of the pendulum in dif- 

 ferent latitudes, ii. 144; on the tem- 

 perature of the Caribbean Sea, ii 

 193 ; comparison of barometrica 

 measurement, with the trigonome- 

 trical determination of a height a 

 Spitzbergen, ii. 217 ; on the diffe- 

 rence in the number of vibrations 

 made by an invariable pendulum ii 

 London and at Greenwich, ii. 360 

 on the ratio of the magnetic force 

 in Paris and in London, ii. 326 

 on the difference in the length o 

 the seconds pendulum in London 

 and in Paris, ii. 329 ; on the dip o 

 the magnetic needle in London 

 Aug. 1821, ii. 155, Aug. 1828, ii 



357 ; on the reduction to a vacuum 

 of an invariable- pendulum, ii. 368 ; 

 on tht feduction to a vacuum of 

 Capt. Kater's convertible pendulum, 

 ii. 381 ; note on the Rev. F. Fal- 

 lows's observations with the pen- 

 dulum at the Cape of Good Hope, 

 ii. 39 ; on the difference in the num- 

 ber of vibrations made by an inva- . 

 riable pendulum at Greenwich and 

 Altona, ii. 403 ; on the correction for 

 variations of temperature, ii. 404. 

 Safety-lamp, Dr. Clanny's, i. 467. 



, Sir. H. Davy's, ii. 32, 35, 



61, 62. 



Salt, analysis of British and foreign, 

 i. 356. 



Saltpetre, on the natural production of 

 on the walls of buildings, i. 509. 



Salts, en super-acid and sub-acid, i. 

 289. 



Sap in trees, on the ascent of, i. 53 ; 

 on the descent of, i. 118, 201 ; the 

 motion of, i. 147 ; the state in which 

 it is deposited during winter, i. 172. 



Saturn, on the figure of, i. 203, 246, 

 298 ; the climate and atmosphere 

 of, i. 246. 



Saussure (Th. de) Sur la decomposition 

 de 1'amidon a la temperature atmo- 

 spherique par 1'action de 1'air et de 

 1'eau, ii. 105. 



Say (Thos.) on the genus Ocythoe, ii. 

 108. 



Schehallien, lithological survey of, i. 

 409. 



Schreibers (Dr. C.) on a doubtful am- 

 phibious animal of Germany, called 

 Proteus Anguinus, i. 47. 



Schroeter (J. J.) on the planet Vesta, 

 i. 270. 



Scilly Islands, on the current to the 

 westward of, ii. 17. 



Scoresby (W.) on the anomaly in the 

 variation of the magnetic needle as 

 observed on shipboard, ii. 108 ; 

 experiments on the magnetical pro- 

 perties in steel and iron by percus- 

 sion, ii. 168, 210. 



Sea serpent, description of an extra- 

 ordinary marine animal, ii. 302. 



Sea-sickness, on the origin of, i. 349. 



Sea- water, on the specific gravity, tem- 

 perature, and saline contents of, ii. 

 73, 111, 178, 355. 

 Sea- worm, on the shell of the, i. 231. 



