458 
INDEX. 
N 
Natron, on a formation of, 427* 
Neill, Mr, on a remarkable shower of haill which fell in Orkney, 
S65. ^ • 
Newton, Sir Isaac, on the double refraction and polarization of light, 
124, 
O 
Ocean, on the temperature of the, 267, 268. 
Occultation of ^ pisces, 429- 
Oersted, Professor, his discoveries on electro-magnetism, 176. 
Ordeal Trial in Congo and Loango, described, 329. 
Orkney Islands, on the remains of trees in the, 209. 
Oxley, Mr, on the variation of the needle, 277. 
P 
?alm Tree in Congo described, 330. 
Pallas, geocentric places of, 431. 
Pallas, M. on the phosphorescence of fluor-spar, 183. Note. 
Parallaxes, new method of calculating, 387* 
Parallel roads of Lochaber, 417* 
Parry’s voyage of discovery, account of, 144. 
Patents, Scottish, 224. 
Patton, Admiral, his inquiries respecting the submarine current at 
the Straits of Gibraltar, 249- 
Pendulum, wooden, account of the going of a clock with a, 355. 
Perkins, Mr, — on the compressibility of water, I76. — on keeping the 
back-water from mills, 439- 
Phosphorescence of fluor-spar, 183. 
Piezometer for measuring the compressibility of water described, 178. 
Pigments, ancient, 427* 
Pine^Martin, cross breed between it and the cat, 208. 
Planets, New, oppositions of the, 197* 
Plants, on the respiration of, JOO. 
Platinum, alloys of, 202. 
Platina, extraordinary mass of, discovered in Peru, 214. 
Polarization of Light, history of the, 121. 
Polarised Light, on the tints of in certain crystals, 339. 
Potassium, on the alloys of, 447, on the motion of these alloys in 
water, 389. 
Potentilla, on a new species of, 195. 
Porcelain-Clay from the Halkin Mountain described, 257. 
Pound, Troy, Dutch, on the weight of it, 449, 
Printing from fusible metal, 451. 
Proteus Aiiguinus described, 398. 
Prussiates, Berzelius’s analysis of the, I6. 
Pyrolignous acid, on the antiseptic power of the, 344. 
Pyroxenes, on the analysis of the, 21, 
