INDEX. 



19 



its use in extracting gold and silver, 

 vi, 3 1C; experiments on, 319; ap- 

 plied to mirror 

 <lnito, description of Ilie city of, i, 



-'i. ofthe pli.in of, i.. 

 If <n i>i(/ t antiquity of horse, v, 085 

 AW;/, itst fi. .* on rocks, i,2,'>d; general 

 observations on, iii, 3; experiments 

 on, iv, 20; causes of, 143; at the 

 equator, 148; on mountains, J49; 

 unusual fall of, 150; violent at Den- 

 bigh, 155; at Rippondcn, 150; salt, 

 ! ">r ; observations on the snine, 158; 

 volcanic, l6l ; of anew kind, 162; 

 of fishes, 166 



Rainbow, an inverted, vi, 524 ; solar 

 and lunar, 528 ; lunar one in Derby- 

 shire, 529 

 Ttaleit/h on the height of mountains, 



i, 260 



Ramtdfte, optical deception at, iv, 516 

 Rarefaction, observations on, iv, 203 

 Rattlesnake, natural history of the, v, 

 566; on the rattle of, 569; on the 

 fascinating power of, 570 ; experi- 

 ments on, 57 1 

 Rat/, his botanical system, v, 10; 



witty remark of, v, 358 

 Reading, in Berkshire, phenomenon 

 at, ii, 53 ; bed of o\ ster shells at, 1 49 

 Re-agents, observations on, iii, 188 

 Realt mount, glory seen on, iv, 530 

 Redbreast, natural history of the, v, 636 

 Red lights in the air, iv, 416 

 Red snow at Genoa, iv, 172; on the 



Alps, 173 

 Refractions, atmospherical and double, 



iv, 514, 516 



Rryuliis, fate of the army of, v, 576 

 Jieicheuait island, description of, iii, 234 

 Rcmora, description of the, v, 508; 



origin of the fable concerning, 511 

 RejMMMM%otl the power of, iv, 56; on 



electric, vi, 24 

 Resitia, in Italy, temarkable well at, 



ii, 229 



Returning stroke in eletricity, iv, 336 

 Revolution, duration of a sidereal, i, 147 

 Ret/hum springs in Iceland, account of, 



iii, I i'J 

 Rhea, or American ostrich, described, 



v, 615 



Rhine, gold in the sand of the, ii, 286; 

 course of the river, iii, 23 



Rhodes destroye.l by an earthquake, ii,'2 

 Rhodope, description of mo-Mr, ii, 408 

 Rhone, account of the river, iii, ^~>; 



|v;ulS'.ir nind on the, iv, 234 

 Rhiilnrb, drscrutiio'i of, v, 19(5; two 

 sorts of, IQgypurgative (utilities of, 

 H.';> / 



ffihar in Hungary, baths of, iii, 165 

 Jtice, on the culture o', 

 Rir/t:nan, professor, death of, iv, 353, 



357 

 Ridis, spontaneous combustion of, iv, 



502 

 Rille, in France, disappearance of the, 



iii, 7 



Ring ouzel, description of the, v, 624 

 Rings, cause of ruiry, v, 316 

 Riobambo, South America, destroyed, 



i, 487 



Rio Janeiro, commerce of, ii, 304 

 Rio de la Plata, description of, iii, 48 

 Rion, lieutenant, sufferings of, iv, 99 

 Rippendon, violent rain, at, iv, 156 

 Rivers, on the course of, i, 317 ; on 

 the origin of, iii, 5; disappearance of, 

 6, description of principal, 10 50 

 Roads, construction of Roman, ii, 137 

 Rochford, phenomenon at, ii, 52 

 Rockets, construction of, vi, 212 

 Rocks, method of blasting, ii, 275 

 Rocks, description of, i, 319; struc- 

 ture of, 320; formation of, 322; on 

 volcanic, 508 ; on the vegetable pro- 

 ductions of, v, 32 

 Rock-bridge in Virginia, described, ii, 



439 



Rock-salt in Cheshire, works of, ii, 369 

 Rochia, Joseph, remarkable history 



of, iv, 177 



Roger Rain's house, Derbyshire, ii, 85 

 Roggewein, voyage of, iv, 89 

 Roman antiquities in Britain, ii, 165, 

 217,221,227; at Hercuianeuni, -.^<J 



empire, extent of, i, 302 



Romans, their improvements,!, 301; 

 their destruction of forests, ii, 135, 

 147 ; luxury of the, v, 619 

 Rome, caverns near, ii, 76 

 Roinaine, M. melancholy fate of, vi, 7 1 

 Rote-hill, Siibsux, phenomenon at, iv, 



420 



Rusia-ba;/, Gibraltar, cave at, ii, 469 

 Rosin, nature of, v, 175 



