Thermometer, Fahrenheit's, [277]

Tides, [78]

Tubes, friction of liquids in, [197]

Twilight explained, [346]

Unison, [268]

Up and down, explanation of, [81]

Vapor, influence of pressure upon the formation of, [292]

Vaporization, [291]

Velocity, relation of, to force, [194]

Velocity, relation of, to shape, [195]