silicious stones cutting away rooks, 188.

Satellites, 53, 54;
motions of, about their centres and about the sun, 53, 54.

Saturn, 38, 53, 57, 396;
cloud bands of, 70;
gaseous wraps of, 97;
path of the earth affected by, 59, 60.

Savages, primitive, students of Nature, 1.

Scandinavia, changes on the coasts of, 96.

Science,
advance of, due to mechanical inventions, 22;
astronomy beginning with, 10;
chemical, characteristics of, 14;
conflict between religion and, 20, 22;
conflict between the Roman faith and, 20;
mechanical inventions as aids to, 22, 23;
modern and ancient, 4;
natural, 5, 6;
of botany in Aristotle's time, 14;
of physiology, 15;
of zooelogy in Aristotle's time, 14;
resting practically on sight, 10.

Scientific development,
historic outlines of, 17;
tools used in measuring and weighing, as an aid to vision, 12.

Sea,
battering action of the, 140;
coast ever changing, 385, 386;
effect of volcanic eruptions on the, 299;
floor deposits of the, affected by volcanoes, 360, 361;
in receipt of organic and mineral matter, 359;
hot and cold currents of the, 102;
littoral zone of the, 351, 352;
puss, 142;
rich in organic life, 352, 353;
solvent action of the, 361;
strata, formation of, 354;
water, minerals in, 185;
weeds, 155, 156.

Seas, dead,
originally living lakes, 200;
water of, buoyant, 199;
eventually the seat of salt deposits, 199-201;
general statement as to division of, 83, 84;
shape of the, 83, 84.

Seashore, air of the, 98.

Seasons, changing the character of the, 61, 62.

Sense of hearing, 9,10;
of sight, 10;
of smell, 9, 10;
of taste, 9, 10;
of touch, 9, 10.

_Seracs_, 214.

Shocks, earthquake. See under EARTHQUAKES.

Shore lines, variation of, 83, 84.

Shores, cliff, 138-142.

Sink holes, 202;
in limestone districts, 253, 254.

Skaptar,
eruption of, 297, 298;
lava from the eruption of, 298.

Sky, mackerel, 35.

Snow, 207-225, 244;
as an evidence of atmosphere, 65;
blankets, early flowers beginning to blossom under, 208;
covering, difference between an annual and perennial, 210;
effect of, on plants,