INDEX. 



N. 

 Newton's theory of gravitation arofe from 



a common occurrence, 150 

 Nicholfon, 311 

 Nitrous gas, its abforption by the falts of 



iron, 107 

 Nitrous oxide, 99. — Its alarming effects 



on Mr. James Stodart, 225 

 Nodules, lblar, 18 

 Nonius, flying, of Mendoza, 8 

 Numbers, Gough on primes and factors, 



3.' — Curious properties of, 314 



O. 



Obfervations of Piazzi and of Zach, on 

 the new planet Ceres, 288, 294 — On 

 the plumb-line and fpirit-level, 312 



Ochres, natural production of, 1.1 a 



Odorous fubftances, their motions on the 

 furface of water, 51 



Oil, its rtrange effect on the extrication 

 of gas by galvanifm, 201 — Conducts 

 heat downwards, 241. — Ufed by pain- 

 ters, on its improvement by Mr. 

 Sheldrake, 259.— Burned on water, 

 297 



Olbers, Mr. 193, 287 



Openings, in the folar atmofphere, 14 



Organ pipes, ftrange influence of, upon 

 each other, 320 



Oriani, 194 



Otomagues, favages who eat a mere earth, 



Oxide, nitrous, 99 — Mr. Stodart feri- 

 oufly affected by breathing it, 225 



Paint, with milk, Sec. 212 



Paper, bleaching of, by Loyfel, 148 



Papin's digefter, 100 



Parmentier, 157.— On the clarifying of 



liquids, 228, 253 

 Payen, 303 



Pearfon, Dr. on James's powder, 22, 23 

 Pearfon, Rev. Wm. his account of the 



new planet Ceres, 284 

 Perez, Cit. Y, on radical vinegar, 39 



Pernety, 213 



Perfpective inftrument, cheap, Ample, 

 and portable, by R. L. Edgeworth, 

 Efq. 281 

 Tfaff, Profeffor, 173 

 Phantafmagoria, 147 

 Phantafms, optical, ib. 

 Philipfthal, Mr. his phantafmagoria, 147 

 Philofophical Tranfaclions, 73 

 Phipfon, Mr. 198 

 Phiogifton, 199 

 Phofphate of iron, native, 238 

 Phofphorus, new and curious inflamma- 

 tions of, 296, 297.— Plentifully ob- 

 tained from fiih bones, 299. — Moves 

 fpontaneoufly on mercury, but camphor, 

 &c. do not, 301 

 Piazzi, M. of Palermo', his new planet, 



72> I93> *9 6 » 287 

 Pictet, Cit. 281, 135 

 Pile, galvanic, its capacity compared with 



electric apparatus, 175, 177 

 Planet new, fee Ceres, 72 

 Platina fufed by galvanifm, 178 

 Piatt, M. 59 



Piumb-iine for aftronomical inftruments*. 

 its limits of accuracy, by Mr. Ez. 

 Walker, 309 

 Pons, 70 

 Pores, folar, 18 



Pott, furgeon, on the cataract, 65 

 Powder, James's, Chenevix on, 22 

 Prevoft, Cit. Benedict, on the motions of 



camphor, &c. on water, 51 

 Prieftley, Dr. 41, 108. — His reply to 

 Mr. Cruiclcfhank, and defence of phio- 

 gifton, 181. — On the pile of Volta, 

 198 

 Prime numbers, curious properties of, 314 

 Prognoftics of the weather from animals, 



&c. 280 

 Prouft, Mr. on the nutriment afforded by 

 various bones, 1 00.— On metallic ful- 

 phurets, 109, 269, 258 

 Pruffian blue, Des Mortiers on, 75 

 Pulvis antimonialis, 22 

 Pyrites, their nature amply inveftigated, 

 109, 269 



