456 INDEX. 
Perkins , Mr, on a steam-engine of great power, 186, 598. — oil crystal- 
lisation under pressure, 188. 
Pictet , M. on the ice-caverns in the Jura and the Alps, 1. — on the mi- 
nerals brought by Mr Clissold from Mont Blanc, 173* 
Pitchstone from Newry, analysis of, 189- 
Plymouth , on the examination of the population returns of, 270. 
Polarisation of light, historical account of discoveries respecting it, 
149, 245. 
Polyzonal lenses, on the construction of, 160. 
Population of Russia, 204. 
Population of North America, on the increase of, 41, 328, — returns of 
Plymouth examined, 270. 
Prisms , on the construction of large ones for optical purposes, 1(?7, 
note. 
Prize offered by the Academy of Berlin for the best theory of haloes, 
393. 
Proceedings of the Royal Society of Edinburgh, 179? 335. — of the Wer- 
nerian Society, ] 80, 386. 
Prout , Dr, on the changes in the egg during incubation, 63. 
Pyro-cilric acid described, 400. 
Pyroxene, green, analysis of, 1 89* 
R 
Rain, account of a great fall of, at the tropics, 185. 
Ram age, Mr, his large reflecting telescope, 393. 
Reflecting microscope, description of a new one, 326, — telescopes with 
several lenses, 391, — telescopes of great size, 393. 
R( fraction, double, observed in compressed glass, and in glass that has 
been quickly cooled, 392. 
Revolutions of the animal kingdom, as indicated by geognosy, on the, 
110 . 
Rewah, on the great waterfalls of, 83, 
Rhine , at Basle, on the quantity of water in the, 399* 
Rhinoceros, Asiatic, on the manners of the, 195. 
Rhinoceros, horn of one found in the Loch of Forfar, 387, 404, 
Ringing walnut-trees described, 194. 
Rock-crystal, on the formation of, ipi. ’ 
Root, on the physiology of the fibres of the, 37, 
Rotation of bodies, on the, 389, 
Rot horn, ice cavern of the, described, 290. 
Royal Society of Edinburgh, proceedings of, 179. 
S 
Schmidt on the height of the atmosphere, 418. 
Schweinitzia, a new genus of plants described, 256. 
Scoreshy, Captain, his discoveries on the East Coast of West Green- 
land, 200,- — analysis of the journal of his voyage, 340. 
Scotland, gleanings of natural history on the coast of, 293. 
Seeheck, Dr, his electro-magnetic experiment, 399. 
Sedgwick, Professor, on basaltic dikes and formations, 390. 
Sheep, on domestic ones become wild, 268. 
Ship, notice respecting an ancient one found at Stranraer, 36. 
