INDEX. 



Haaktion of heat, inftrument for meafur- 



ing the eftefts of the, 62.— Is increafed 



by bodies which facilitate the paffage of 



heat, 194 



Rainbow, fupernumerary, caufed by the 



interference of light, 1 35 

 Raflileigh, P. Efq. 14 

 Raymond, 142 

 Rays, calorific and frlgorific may be the 



fame, 197 

 — — dark folar, experiments on, 140 

 R. B. dcfcription and drawing of his in- 

 ftrument for drawing in perfpeftive, laa. 

 —Another for delineating ovals, 123.— 

 Projeft for a perpetual motion, 211, — 

 Defcription and drawing of his new pa- 

 rallel rule, 213 

 Reaumur, 182 

 Red enamel, 268 



Rheumatifm, cure of by galvanlfm, 246 

 Richter, Mr. 180 

 Ritter, 140 



Rocks, improved procefs for Hafting, 230 

 Roy, Gen. 112, 230 

 Rule, parallel, defcription and drawing of 



a new, 213 

 Rumford, Count, on the nature and mode 

 of communicating heat, 58, 193, 102, 

 142.— Account of a curious phenome- 

 non obferved on the Glaciers of Cha- 

 BQOuny, 207 



S. 



Sage, B. G. on a method of giving the 

 colour, grain, and hardnefs of fteel to 

 copper, 267 



Salop, mucilaginous powder from the root 

 of, 234 



Salts, triple of platina, 67 



Sand, its ufe in blading rocks with gun- 

 powder, 231 



Sauffure, la, 57 



Scheele, 290 



Sealing-wax, cxperimentt on its power of 

 abforbing air; 26s 



Seeds, perifh when deprived of oxigen, 



Seguin, M. on chamoyinjf leather, 251 



Sennebicr, 196 



Seymour, Lord Webb, 104 



Sheldrake, Mr. T. on Tingry's errors re- 



fpedting copal varnifhes, 151 

 Ships, on an improved method of con- 



ftrufting, 166 

 Silex and carbonate of lime, combination 



of, lOI 

 Silver, the true melting point of, 99 (note) 

 ■ ■■■■■, fulminating, accident with, 203 

 Smeaton, Mr. 215. — His pendulum, 229, 



230 

 Smith, Dr. 162 



Smoke from a candle facilitates thepaflfage 

 of heat, 61, — Prevents water from boil- 

 ing, 202 

 Soda and platina, method of preparing a 



muriate of, 67 

 Solard, 283 



Sound, ftrong refemblance of it to llght„ 

 138.— On the caufes of the augmenta- 

 tion of its intenfity in fpeaking trum- 

 pets, 283.— Is notdiminiihed by an In- 

 ternal covering of wool, 288.— Nor does 

 its Intenfity arife from refledlion, 289 

 Soy, Chinefe, method of preparing, 237 

 Speaking trumpets, on the caufes of the 

 augmentation of the intenfity of found 

 in, 283."— -Hiftory of the Invention ot, 

 ib.— Proportions of a conical, aS4,— 

 Augmentation of found in thofe with 

 cylindrical tubes, 287. — It is not owing 

 to the refiedion of the fonorous rays, 

 289 

 Spermaceti, on the latent heat of, 45 

 Squares, on the computation of tables of> 



4, 123, 171 

 Squills, vernal, mucilaginous powder from, 



232 

 Star, difcovery of a new moving, iix 

 Starch, Is a generic term, 70.— Noteafily 

 decompofed, 74.— Experiment on its 

 union with tan, 75.— Chemical exami- 

 nation of, 76 

 — — ' of pepper, 77 



Steam, 



