Part 105

Rivers, 134.

Rivulets, 131.

Satellites, 80, 111, 113.

Saturn, 85.

Scales, or balance, 55.

Screw, 54, 67.

Shadow, 110, 111.

Siderial time, 106.

Sight, 165.

Signs of the zodiac, 86, 93.

Smoke, 14, 29.

Solar microscope, 202.

Solstice, 100, 102.

Sound, 151. acute, 155. musical, 155.

Space, 33.

Specific gravity, 123. of air, 140.

Spectrum, 190.

Speaking-trumpet, 154.

Sphere, 26.

Springs, 130.

Spring tides, 116.

Square, 81, 85.

Stars, 77, 86, 102.

Storms, 147.

Substance, 10.

Summer, 76, 100.

Sun, 71, 75, 78, 162, 182.

Swimming, 41.