652 
extirpation of, 76 
wild American, extirpation of, 7§ 
Po, sediment of, 276-284 
floods of, in 1872, 279, note 
embankments of, 507 et segg. 
geographical character of, 507, note 
inundations of, 509, note 
discharge of, 519, note 
Ponps, objections to draining, in Catholic coun- 
tries, 529, note 
POWDER, consumption and uses of, 406, note 
PRAIRIES, character and origin of, 390, note 
INDEX. 
RIvERs, fertilizing slime of, 244, note 
origin of, 268, 505, note 
transporting power of, 274 
sediment of, its extent, 275 
injury to their banks by lumbermen, 364 
underground and submarine, 472, note 
intercommunication of, 497, nove 
diversion of water from, effects of, 498, note 
effect of obstructions in, 505, note 
confluence of, effect on the current below, 
505, note 
great, proposed diversion of, 624 
PRECIPITATION, absorption of, by earth, 21, 215, | RrvER BEDS, natural change of, 498 
note 
in the United States, 217, note 
in Lombardy, 456, note 
extraordinary, at Genoa in October, 1872, 
279, note 
how much lost by evaporation, 472 
plans for economizing, 487 
QUADRUPEDS, domestic, origin and transfer of, 
86, 87 
domestic, number of, in the United States, §8 
wild, number of, in the United States, 88 
extirpation of, 92-96 
QUARRIES, extent of, 403, note 
QUEBEC, high tides at, 360, note 
lumber trade of, 360, note 
RaBBIT, injurious in Australia, 89, note 
RaILways, scientific uses of, 53, note 
consumption of timber by, 355 
Rarn, summer, how far lost by evaporation, 216 
RAIN WATER, its absorption and infiltration, 474 
economizing its precipitation, 487 
RAVENNA, cathedral of, 62, note 
Rep SEA, richness in organic life, 98 
diversion of the Nile to, its effect, 621 
REPTILES, utility and destruction of, 125 
RESERVOIRS, natural subterranean, 474 
as remedies against inundations, 492 
natural, 494 
REVENTLOV’s organization of dune economy in 
Denmark, 595 
REVOLUTION, French, influence of, on woods, 354 
RHINE, discharge of, in flood, 237, note 
- ordinary discharge of, 519, note 
sediment of, 543 
diversion of, 624 
RuHONE, Gischarge of, 519, note 
Rice, cultivation of, unhealthy, 467 
climatic limits of, 468, note 
introduced into Europe by Moors, 468, note 
RiTTER’s opinion on Egypt erroneous, 455, note 
artificial change of, 498 
in Egypt, 498 
in Italy, 499 
in Switzerland, 500 
RIVER DEpPostts, 504 
of the Po, 279, 506, note 
of the Nile, 525 
of the Tuscan rivers, 525 
RIVER EMBANEMENTS, 501 
their effects, 502 
RIVER MOUTHS, obstructions of, 522 
accelerated by man’s influence, 523 
effect of tidal movements, 524 
RoBIn, the American, voracity of, 121, note 
Rock, generally permeable by water, 285, note 
cuttings in England, 403, note 
soit beneath, 628 
covering with earth, 629 
ROMAN CAMPAGNA, insalubrity of. 447, note 
RoMAN EMPIRE, physical advantages of its ter- 
ritory, 1 
physical decay of its territory, 3, 5 
causes of this decay, 5, 7 
Rome, commerce of, passive, 65, note 
objects of, 65, ote 
insalubrity of, 158, note 
Romans and Greeks, great material works of, 426 
contempt for artisans and engineers, 426 
Roots of trees, influence of, on drainage, 242 
Rozzr’s plan for diminishing inundations, 512 
RUBBISH HEAPS in Egypt, 641 
of Monte Testaccio, 641 
RUDE TRIBES, continuity of arts among, 17 
commerce of, 18 
relations to organic life and nature, 38, note 
Russia, diminution of forests in, 824 
diminution of forests in, effect of, on rivers 
and lakes, 325, note 
attempts to reclaim the sands, 608, note 
SACRAMENTO City, effect of river dike at, 
508, note 
