I 



N 



D 



E 



X. 



5§K 



Petrol, or Petroleum, ii. tot 

 Petroleum induratum, ii. ioj 

 Peyff r, i. 233 



Pfaflf, Dr. on Polynom'als, i. 47. 361, ii. 9 

 Phenomenon, remarkable, Optical, i. zi$ 

 Philadelphia, Chemical Society of, ii. 376 

 Philipps, Samuel, ii. 96 

 Philolaub, ii. 185 



Philolophical Tranfaftions of the Royal So- 

 ciety, i. 191. ii. 142, 420- Correfpand- 

 ence, i. 185, 528, 430, 431, Society of 

 Manchefter, IViemoirs of, ii. 188 

 Phofphori, Light of the. Natural, ii. 134 

 Phofphoric Acid contained in the Urine of 

 Animals that feed on Vegetables only, 

 ii. 71 

 Phofphorus, Combuftion of, in vacuo, i. 

 236, 279. Obftrvations on, and Experi- 

 ments with, by Brugnatelli, i. 444. Sup- 

 po'ed Apptarance of Light in Azotic 

 Gas, ii. 8. Its Combuftion, ii. 498 

 Photius, ii. 136 

 Picard, i. 99 



Piftet, ProfelTor, i. 97. ii. i6o, 414 

 Pinchbeck, Mr. i. 6i 

 Pigotr, Edward, Efq, on the Brightnefs of 



two fixed Stars, i. 191 

 Pifo Cneius, ii. 254 



Pifton, Metallic of Mr. Cartwrighr, ii. 364 

 Pitch Mountain, or Mineral, ii. 203 

 Pius III. Pope, i. 75 

 Planetary Atmofpheres, ii. 40 

 Planets, Motion of, ii. 41. Inftrument for 



exhibiting Jupiter and Satellites, ii. 122 



Plants, Irritability of the Pollen of, i. 471 



Platina, Salts and Precipitates of, i. 537. 



Amalgam of, i. 53S. Aftioa of Nitre on, 



ii. 30 



Playfair, John, on the Trigonometrical 



Tables of the Bramins, ii. 167, 192 

 Pliny, i. 107, 137. ii. 255, 256, 259 

 Plumb Line and Spirit Ltvel, i. 134 

 Plutarch on Gravitation, ii. 85, 184 

 Polarity, magnetic, of a Mountain, i. 97 

 Poleni, ii. 172 



Pollen of Plants, Irritability of, i. 471 

 Polybius, ii. 238 

 Polynomials, i. 47 

 Polytechnic School, i. 93, 141 

 Poor, report of Society for bettering the 



Condition of, i. 190 

 Poplar, Athenian, ii. 334 

 Population of Europe, ii. 436 

 Porta Baptifta, ii. 90 

 Portable Eleftrical Machine, Defcription of 



a New, i. 506 

 Porterfield, Dr. i. 305 

 Pot-afti, Economical Procefs for obtaining 

 Pure, i. 329. In Volcanic Produftions, 

 ii. 289 

 Pott, i. 142 



Poultry, Pricesofat different Periods, ii. 184 

 Pound, ii. 128 

 Precipitates of Platina, i. 537 

 Prelong, Cit. i.82 

 Preparation of the oxygenated Muriate of 



Pot-afli, ii. 290 

 Prefs, Hydroftatic of Bramah, i.29 

 Prefervation of Gun- powder, Mode of, 1,262 

 Prevoft, Benedift, on Odours, i. 153 

 Prevot, Cit. i. 97, 153, 154, ao5, 431 

 Vol. I. July 1799. 



Prices of various Articles at different Pe- 

 riods, ii. 284 

 Prieftley, Dr. i. 67, 182, 261, 265, 314, 



481, 5*7. 546- !>• 95» 96, i9<'> i'9. 



243, 246, 313, 314 

 Prieur, i. 44. ii. 262 

 Piince, Rev. J. his Air-pump defcribed, i. 



121, 441. ii. 29 

 Printing by Cylinders, i. 18. From Glafs 



Plates, ii. 60 

 Prints, Method of Cleaning and Bleaching, 



ii. 26; 

 P|rior, Mr. John, his new Efcapement, ii. 



363 



Prize Donation by Count Rumford, i. 188 



Procefs for making Artificial Cinnabar, li. 2. 

 For refining of Saltpetre, ii. 23. Of Bleach- 

 ing, ii. 268 



Projeflion of the Earth, ii. 39 



Prony, i. 46, 420, 421. ii. 173, 231 



Propagation of Sounds, Experiments on, by 

 Perrole, i. 411. Of the Zebia, curious 

 Faft, relpe£ting the, ii. z67. 



Properties of Light, ii. 147, 194 



Proportional CompaiTcs, ii. 89 



Prouft, i. 184. On Pruffian Blue, i. 453. ii. 

 97. His Memoir on the Tanning Prin- 

 ciple, ii- 337. 339. Enquiries concerning 

 Tin, ii. 515 



Pruflian Blue, Enquiries concerning the Na- 

 ture of, by Prouft, i. 453. Folfil, from 

 B.razil, ii. 508 



Prulfiates of Iron, White and Blue, i. 454 



rrulfic Colouring Principle, i. 142. 



Ptolemy, i. 107. li. 238, 259 



Public Loans, Prize Queftion on, ii. 238 



Pumice, Analyfis of, ii. 289 



Pump, Air, i. 119. New Conftruftion of, i. 

 441. By Sir Georg':: S. Mackenzie, ii. 

 28. Common, i. 120. Worked by the 

 Wind, rendered fteady, ii. 71 



Purification of fixed Alkalis, i. 164. Of 

 011,11.46. Of Water, ii. 213. Of Mer- 

 cury, i. 181. Of Potalh economical Pro- 

 cefs for, i. 329 



Purity of Drugs and Medicinei, Examina- 

 tion of, ii. 118 



Putois, Sieur, ii. 233 



Pufchkin, Count Mufiin, i. 537 



Pyrenean Mountains, the moft elevated 

 Summit, calcareous, ii. 511 



Quadratic Equations, Rule for folving, i. 



»39 



Queflion, Philofophical, i. 284. Mathema- 

 tical, i. 92, 138, 186, 188, 238, 284, 41 1 



Qulckfilver, Method of Congelation of, by 

 Walker, ii. 497 



R. 



Raab, Mademoifelle, ii. 248 



Rachitis, or Rickets, Nature and Treatment 



of, i. 174, 200 

 Rain, preceded by Drynefs of the Atraof- 



phere, i. 51 1 

 Rambouillet, M. ii. 308 

 Ramond, his Excurfion to Mount Perdu, 



ii. 510 

 Kamuntiini) Mr. i. 328 



Ramfden, Mr. i. 310, 476. His Acco,un,t qf 

 Lenfes Maftique^s, ii. 96, 234, 42J 



Ranchon, Mr. i. 201 



Randel, Ad. FiiJ. on the Powers of Euro- 

 pean States, i. 47 



Raflilcigh, Philip, M.P. F.R.S. and F.A.S. 

 Specimens of Minerals, i. 96 



Rafpe, Mr. ii. 346 



Raw Silk, Bleaching, i. jit, S8 



Read, Mr. John, ii. j63. On the Doufaler, 

 ii.495 



Reaumur, i. 36. ii. T90, 2S6 



Red Lead of Siberia, new Metallic Acid in> 



Reflection of Light, i. 554. ii. 148, 198 



Rcflcftors, ii. 197 



Refraition, Aiim^fpherical, fingular Inftance 

 of, by W. Latham, Eliq. ii. 41 7 



Refrafilion, A( hromatic, by a fingle Surface, 

 i. 7. Horizontal, fingular EfFedts of, i, 

 146, 152. Correftions for, i. 1 50 



Refraftive Puwer of Fluids, meafure of, i. t 



Re-t'iomontanus, i. 108. ii. 84 



Rehe, Mr. ii. 421 



Re-id, Dr. on Vifion, i. 549 



Reil, i. 255 



Renaud, Mr. i. 579 



Rennel, James, Elq. F.R.S. his Obfervations 

 on North Africa, ii. 253, 280, 483, 350 



Rennie, John, efq. ii. 47, 95 



Refonance of M'llical Inftruments, i. 416 



Revival of Infefts after Immerfion in fer- 

 mented Liquors, ii. 353 



Ribbands, Count Rumford's Experiments 

 on the Reduflion of Metallic Oxyds, at- 

 tached to, ii. 400 



Richmond, Duke of, i. 377 



Richtcr, Mr. ii. 342 



Rickets, or Rachitis, Nature and Treatment 

 of, i. 174, 200 



Rifled Shot, Experiments with, i. 382 



Rings, Fairy, i. 546 



Rinmann, i. 77. ii. 105 



Rios, Don Jofef de Mcndoza, Refearches ia 

 Aftronomy, i. 19 



Rittenhoufe, David, Efq. i. 13, 152 



Rivard, ii. 378 



Rivers, Edtlies of, ii. 492 



Rivers of Guiana, it. 348 



Robertlbn, Dr. i. 108. Mr. his Gunter's 

 Rule, i. 374. 



Robifon, Profcflbr, ii. 199 



Robins, Mr. on Gunpowder, i. 459 



Rochon, Abbe, on Achromatic Lenfes, ii. 23 J 

 His Wire-cloth for Lanthorns, ii. 412 



Rock Cryftal, produced in the humid Way, 

 by Tromenfdorff, i. 217 



Roebuck, John, M.D. ii. 191 



Roederer, Cit. ii. 238 



Rollo, Dr. i. 285, 341. ii. 427 



Rom6 de L'lfle, i. 25 



Romieu, i. 153, 205, 2o5 



Roquefort, Cold Caves of, 233 



Rofe Water, to make at all Seafons, i. 80. 



Rofe, Mr ii. 372 



Rofeapcnna, Manfion of, deftroyed|by the 

 Sands, ii. 3S5 



Rotation of the Earth, ii. 39 



Rouelle, ii. 71 



Rouland, his Silk-machine for Eleftrjcity,; 

 ii. 420 



Rowley, Mr. ii. 12a 



A £ Roy, 



