INDEX. 



PcIIetier, 9; it)8 



Pendulum, Mr. Troughton's, 1— Wooden 



rod, 2' — Improved, 3 

 Pennington, Mr. 4 

 Perrole, 55 

 FhilUps, Mr. R. 104. 

 Phofphorus, eafy method of making the 



very combuftible oxide of, 136 — Aftion 



of on metallic falutions, 138 — 141 

 Pigott, E. Efq. his inveftigation of the 



changes of the ftar in Sobiefki's fhield, 



271 — 281 

 Piai, Prof, his letter on corindon found 



in Italy, 103 

 Planet Junq,, note on, 57 — Juno, Ceres, 



and Pallas, geocentric places of, 100 — 



102 



Plants, methods of preferving, 236, 240 



Platina, crude, cxanrJnation of by MefTrs. 

 Tennant and Woollafton, 59 — New 

 metals foUndiin,,. 59, 163 — And mer- 

 cury, adlion of on each other, 162—182 

 —How fufcd by Mr. Chenevix, 166 — 

 Method of coating polifiied fteel and 

 brafs with, 282 



Prefs for hotaoicaj fub]e£ls defcribed, 236 

 —240 



Prieftlcy, Dr. 66, 79, 81, 82, 83 



Prize queftions, 59, 299, 300 



Prony, 299 



Proufi-, 10, 75, 164 — His experiments on 

 pyrites, 12 — Difcovery of two kinds 

 of honey, 61 



Pyrites, comparative analyfis of different 

 kinds of, 6—^17 



Pyrometer, new, 341 



fjuickfilvcr, a£tlon of phofphorus on fo- 



lution of, 139 — And platina, action of 



en eachoiher, 162 — 182 — Recent mu- 



^i((ttate of tin the mdft delicate tell of, 179 



R. 



Rawlinfon, Mr. James, his improved mill 



for levigating painters' colours, 119 

 Reaumur, jS 



Reid, Mr. T. on the conftrudlon ©f 



time-keeping machines, 1 — 5 

 Refpiration, concife view of the theory of, 



79 — 86 — Mufcles concerned in, of a 



mixed nature, 262 ., , 



Richter, failure of his attempts to produce 



palladium, 62, 167 

 Rltter, his miftake refpefting the charged 



pile, 144 — On the galvanic rank of mi- 

 nerals, 169 

 Robertfon and SacharofF, moft remarkable 



t^s and obfcrvations in th^ir aeroftatic 



voyage from Feterfburgh, 5a — 55 

 Robifon, Prof, his meafure of forces, 



151, 265 

 Romme, 299 

 Ropes weakened by overtwiftlng, 38— 



And by tarring, 39, 42. — Perhaps 



ftrengthened by tanning, 42 

 Rofe and Gehlen, failure of their attempts 



to produce palladium, 61, 164 

 Roxburgh, Dr. W. j on the culture and 



comparative ftrength of hemp andothar 



vegetable fibres, 32 — 47 



• W. jun. 42 



Roy, Julien le, 4 



Peter le, 5 



Rumford, Count, on the temperature of 



water when its denfiiy is a maximum, 



225—235 

 RuflTian voyage round the world, 6»'''''''A 



Sacharoff" and Robertfon's aeroftatic Yoy- 

 age, 52—55 



Safety valve, containing a vacuum valve 

 in the fame hole, 243 



Sage, J 38 



Sago, the pith of the arrow palm, 33 



Saline waters. Bavarian method of eva- 

 porating, 47—49 



Saufleur, Tbeod. de, 158 



Sauveur M. his eftimate of a hoffe-power, 

 146 



Sawyer, Mr. 167 



Scapement, crank. Invented by Soumllle, 



4— Bad, ib,— Duplex, 5— Detached, ib. 



3-chnjidtj 



i 



