INDEX. * 425 



Sponge, experiments on the bleaching of, 402, 403 

 ^'prm^fs for carriages, observations on, 97, 98 

 Steam-engines, method of securing, 385, 386 

 Steel, action of iron in motion upon, 160-162. Menstruum foe 

 etching steel plates, 175. Mode of preparing damasked steel, 

 386, 387 

 Stomachs of animals, on the nature of the acid and saline matters 



usually existing in, 142-144 

 Stone'Bridges, influence of temperature on, 371 

 Structures of rocks, observations on, 60-80 



Sulphates, metallic, experiments on the decomposition of, by hydro- 

 gen, 392-394 

 Sulphur Mountain of Ticsan, account of, 406, 407 

 Sulphuret oi c'axhoxi znA ammonia, on the re-action of, 149-156. 

 Facts tovrards the chemical history of the sulphuret of mercury, 

 922-295 

 Sulphuric Acid of Nordhausen, researches on, 145-148 

 Sun, temperature of, 385 

 Superior (Lake,) notes on the geography and geology of, 1-34, 



228-269 

 Swainson (W[\lia.m, Esq.,) A monograph by, of the genus ancillaria, 



272-289 

 Taylor (Dr. Brook,) his method of solving the problem of atmo- 

 spherical refraction, 346-358 

 Tea, adulteration of, by the Chinese, detected, 166 

 Temperature, influence of stone bridges on, 379 

 Test, elder-berries used for, 400 



Thouin (M.,) on a mode of planting through trees, 409, 410 

 Titanium, experiments on, and combinations of, 174, 175. Tlie 



presence of, in mica, confirmed, 392 

 Travellers, use of the pocket box-sextant to, 50-60 

 Trinkets of gold, suggestion for cleansing, 179 

 Turrell's menstruum for etching steel plates, 175 



Upas poison, active principle of, 176, 177 

 Uranium, native sulphate of, discovered, 409 



Vapours, metallic, method of condensing, 270, 271 



Vauquelin (M.,) experiments of, on the active principle ofoolocynth, 



400, 401. And of the Daphne Alpina, 401, 402 

 Velocity of sound, results of experiments on, 162, 163 

 Vesuvius, account of the volcanic saline matter of, 407 

 Vegetable Life, power of, 4 1 3 



Vogel (M.,) process of, for bleaching sponge, 402, 403 

 Volcano of mud, eruption of, in Sicily, 193, 194. Account of tlie 

 volcano of Puracu, 404-40G. Obsidian thrown out by the vol- 

 cano of Sotara, 408 

 Voltaic Pile, on the distribution of electricity in, 171 , I 72 

 Vol. XVllI. 2 1' 



