Radiator, electric, 3, 79
Radiograph, self-recording, 338
„, diurnal record of light by, 344, 345
Receivers, automatic for electric radiation, 125, 161
„, galena, universal type of, 269
Recorder, Mechanical lever, 261
„, Magnetic, 263
„, Photographic, 308
„, Resonant, 364, 366, 368
„, Conductivity, 169, 230
„, Crescographic, 347
„, Crescographic Magneto, 357
„,„Balanced, 351
Refraction, electric index for glass, 41
„,„„„sulphur, 30
Response, electric, of metals, 266
„„„„, effect of increasing intensity of stimulus on, 295
„„„„, effect of variation of temperature on, 257
„„„„, effect of chemical reagents on, 274
„„„„, effect of poison on, 274
Retina, artificial, 269
Rhythmic tissue in plant and animal, 372
Selective conductivity, exhibition of, by crystals, 71
Self-recovering receiver, perfect type of, 173
„„„, negative response exhibited by, 172
„„„, effect of cyclic E. M. F. variation on, 248
Silver, characteristic curve of positive type given by, 246
„, two varieties of, 146
„, variation of current and resistance with increasing E. M. F. in, 247
Steam, effect of, in abolishing response of plant, 314
Stimuli, effect of superposition of, in living tissues, 313
„,„„„„, in metals, 201
Stimulus, opposite effects of strong and feeble, on electromagnetic receivers, 135, 181
„„„„„„„, on response of metals, 302
„„„„„„„, on response of plants, 256
„, similarity of effect of, on living and non-living, 253
„, Subminimal, effect of, 181, 203, 297
Stimulants, effect of, on inorganic response, 274, 300, 301
„„„„, on response of leaf, 321
Strain cell, effect of single stimulus on, 198
„„, effect of continuous stimulation on, 202
„„, irreversible molecular effect of torsion on, 197
Strained dielectric, polarisation of electric ray by, 19
Stratified rocks, polarisation of electric ray by, 20
Sulphur, electric index of refraction for, 30
