Part 43

Dissonance, explanation of, 42; definition of, 33, 44. See Consonance.

Distances, estimation of, by the eye, 68 et seq.

Dogs, like tuning-forks, 23; their mentality, 190.

Domenech, Abbé, 92.

Dramatic element in science, 243.

Drop of water, on a greased plate, 8; on the end of a stick, 8; in free descent, 8.

Dubois, 218.

Dubois-Reymond, 370, footnote.

Dufay, 271.

Dynamics, foundations of, 153 et seq.

Ear, researches in the theory of, 17 et seq.; diagram of, 18; its analysis of sounds, 20 et seq.; a puzzle-lock, 28; reflected in a mirror, 93; no symmetry in its sensation, 103.

Earth, its oblateness not due to its original fluid condition, 2; rotation of, 204; internal disturbances of, 285.

Economical, nature of physical inquiry, 186; procedure of the human mind, 186; order of physics, 197; schematism of science, 206; tools of science, 207; coefficient of dynamos, 133.

Economy, of the actions of nature, 15; the purpose of science, 16; of language, 191 et seq.; of the industrial arts, 192; of mathematics, 195-196; of machinery, 196; of self-preservation, our first knowledge derived from, 197; generally, 186 et seq., 269.

Education, higher, 86; liberal, 341 et seq., 371.

Efflux, liquid, 150.

Ego, its nature, 234-235.

Egypt, 234.

Egyptians, art of, 78 et seq., 201.

Eighteenth century, the scientific achievements of, 187, 188.

Eleatics, on motion, 158.

Electrical, attraction and repulsion, 109 et seq., 168; capacity, 116 et seq.; force, 110, 119, 168; spark, 117, 127, 132, 133, 190; energy, measurement of, 128 et seq., 169; currents, conceptions of, 118, 132, 135-136, 226-227, 249, 250; fluids, 112 et seq., 228; pendulums, 110; levels, 173; potential, 121 et seq.; quantity, 111, 118, 119.

Electricity, as a substance and as a motion, 170; difference between the conceptions of heat and, 168 et seq., rôle of work in, 120 et seq.; galvanic, 134. See Electrical.

Electrometer, W. Thomson's absolute, 127, footnote.

Electrometers, 122, 127.

Electrostatic unit, 111.

Electrostatics, concepts of, 107 et seq.

Elements, interdependence of the sensuous, 179; of bodies, 202; of phenomena, equations between, 205; of sensations, 200; used instead of sensations, 208-209.