Index, 311 



Starch, chemical remarks on, ii. 280. 



Stars, two sorts of, i. 256 number and distance of the 

 fixed stars, 257, 258 the constellations, 259 unformed 

 stars, 26l. 



Steam, its weight compared with that of water, ii. 75,76. 



Steam-engines, their operation explained, i. 60. 



Steel, account of, ii. 251. 



Steelyard, principle of this instrument, i. 235. 



Strontian, account of this kind of earth, ii. 1Q(5. 



Stony substances. See Earths. 



Strata of the earth, various opinions concerning the, ii. 171 

 to 174. 



Style, alterations in the, why introduced, ii. 17. 



Suber, nature of, ii. 284. 



Sublimation, process of, ii. 81. 



Suction, the idea of this is a vulgar error, i. 73. 



Sugar, chemical remarks on, ii. 275 to 277. 



Sulphates found in mineral waters, ii. 25(J. 



Sulphur, a simple combustible substance, ii. 36 chemical 

 account of it, 51, 204 to 207. 233. 28Q how detected 

 in waters, 264. 



Sulphuric acid, its nature and properties, ii. 147 to 154 

 dangerous experiment with and oil of turpentine, 151, 

 152. 



Sulphuric ether, nature of the fluid so called, ii. 217. 



Sulphurous acid in mineral waters, ii. 258. 263. 



Summer, our distance from the sun is greater in this season 

 than in winter; this paradox explained, i. 273, 274. 



Sun, its diurnal motion apparent and not real, i. 1 expe- 

 riment and calculation on the degree of its continual 

 exhaustion, 140, 141 lecture on the sun, and his real 

 and apparent motions, 270 constitution of the solar 

 system, ib. apparent diurnal and annual motions of 

 the sun accounted for, ib. his distance from us greater 

 in summer than in winter; this paradox explained, 

 272, 273 present difference between the nominal and 

 real places of the signs of the zodiac, 274 difference 

 between solar and sicleral time, 276, 277 form of 

 the sun, 280 spots on his disc, their number and mag- 

 nitude, ib. conjecture concerning them, 281 they 

 produce the discovery of his form, and revolution on his 

 axis, 282 phenomenon of the zodiacal light, ib. 

 tables of the diameters, magnitude, density, and solidity 

 of the sun and the primary planets, 2QO u/294 method 



