INDEX. 



Parmentier, 141 



Peat, on its ufe as fuel, 207. — Chemical 



• remark on, 213 



Pearfon, Dr. 47. — On the life of fulphate 

 of iron as a manure, and on the efficacy 

 of paring and burning land, 206 — 239 



Pendulum, ufe of a large block of ftone 

 in fixing a, 72. — Imperfections of the 

 compound, 73. — Various conftructions 

 of the circular, 76. — An ofcillatory or 

 rolling, 77, — On the properties of the, 

 158 



Petrofiiex, formation of, 166 



Phofphate of cerium, II 



Piarzi, Mr. Jofeph, 302 



Piclet, M. 1—92 



Pine's pendulum, 72 



Phtina, two new metals, iridium and of- 

 mium, obtained from, 24. — On a new 

 metal, rhodium, found in crude, 34. 



Playfair, Prof. 167 



Plot, Dr. 115 



Porcelain of Reaumur, nature of the, 59 

 —123 



Porphyry, formation of, 168 



Porta, J. P. 150 



Prize qu,eftions, 301 



Prouft, 268 — 273 — 301 



Fruffiate of cerium,, 1 1 



of potafh, on the poffibility of 



obtaining it pure, 32 



Ptolemy, 146 



1'yritci, compaiative analyfis of different 

 kinds of, 271 



Pyromctets, alledged defects in, 74.— 

 Methods by which they have been ob- 

 viated, 79 



0^ 



Q^eiiions, prize, 3d 



R. 



Ragftone, analyfis of, 115 

 Ramf<kn, Mr. the inventor of an initru- 

 ment for drawing pcrfpeclivc, 4. — Kis 

 icterj So 



Reaumur, 59 — 123 



Reboul, 301 



Refin of lac, properties of, 97 



Refms, the action of alcilies on, 245 



Rhodium, a new metal found in crude 



platina, 34 

 Richter, 279 

 Robifon, Prof, on fulphate of iron found 



in peat-afhes, 242 

 Rouelle, 141 

 Rouppe, M. 14 — iS 

 Roxburgh, Dr. 45 

 Rult in corn, on the caufe of the, 225 



Sallow, abfoibent power of the charcoal 

 of, t 5 



Salt of peat, on its ufe as a manure, 207, 

 —Chemical examination of, 210 



Salts, metallic, on their effects on vege- 

 tation, 241 



Sandarach, experiments en, 246 



Sap, experiments and obfervations on its 

 motion in trees, 289 



Saron, 82 



Saunders, Mr. 45 



Sauffure, 287 — 297 



Scheele, his method of obtaining bensoic 

 acid, 87— 141— 261 



Schiftus, a remarkable, 184. — Analyfis 

 of, 187 



Schoerbing, M. C. on a method of bleach- 

 ing cotton, and of giving a permanent 

 red to cotton and linen, 126 



Sculpture, an ancient Egyptian, fuppofed 

 to relate to aftronomy, 4 



Serum of milk, chemical examination of, 

 258 



Simons, 301 



Smithfon, Mr. 122 



Sound, experiments and obfervations on, 



' H 



Spallanzani, 1(19 



Spar, formation of calcareous, 166 

 Speaking-trumpet, mathematical theory 

 of the, 160 



Spectacle , 



