INDEX.

Himstedt and Nagel action of radium rays on the eye, 217
Hofmann, Gonder, and Wölfl properties of radio-active lead, 27, 413
Hofmann and Strauss radio-active lead, 27
Hofmann and Zerban connection of activity of thorium with uranium, 29
Huggins, Sir W. and Lady spectrum of phosphorescent light of radium bromide, 205
Hydrogen production of, by radium rays, 215
Induced radio-activity (see Excited radio-activity)
Induction radio-active, 24 meaning and examples of, 415 et seq.
Insulators conduction of, under radium rays, 209
Iodoform coloration produced in, by radium rays, 214
Ionization theory of, to explain conductivity of gases, 31 et seq. by collision, 39, 57 variation of, with pressure of gas, 61 et seq. variation of, with nature of gas, 64 comparison of, produced by rays, 111, 194 production of, in insulators, 209 total, produced by 1 gram of radium, 433 et seq. natural ionization of gases, 531 et seq. connection of, with phosphorescent and photographic actions, 549
Ions in explanation of conductivity of gases, 31 et seq. production of, by collision, 39, 57 rate of recombination of, 40 et seq. mobility of, 42 et seq. difference between mobility of positive and negative, 43 et seq. condensation of water around, 46 et seq. difference between positive and negative, 49 charge carried by, 50 diffusion of, 51 et seq. charge on an ion same as on hydrogen atom, 54 number of, produced per c.c., 54 size and nature of, 55 et seq. definition of, 56 et seq. velocity acquired by, between collisions, 58 energy required to produce, 58, 551 comparative number of, produced in gases, 65 disturbance of potential gradient by movement of, 65 production of, in insulators, 209 number of, produced by α particle, 433 number produced per c.c. in closed vessels, 533 et seq.
Joly motion of radium in an electric field, 211 absorption of radium rays by atmosphere, 492 (see footnote)
Kaufmann velocity of cathode rays, 75 variation of e/m with velocity of electron, 127 et seq.
Kelvin theory of radio-activity, 441 age of sun and earth, 492, 493
Kelvin, Smolan and Beattie discharging power of uranium rays, 7
Kleeman and Bragg theory of absorption of α rays, 172 et seq. relation between ionization and absorption, 174 et seq. range of α rays in air, 174 four sets of α rays from radium, 174 et seq.
Kohlrausch conductivity of water altered by radium rays, 208
Kohlrausch and Henning conductivity of solutions of radium bromide, 208
Kunz phosphorescence of willemite and kunzite, 203

548