- Disintegration account of theory of, 234, 325, 445 list of products of, 448 rate of, in radio-elements, 457 emission of energy in consequence of, 474 et seq. helium a product of, 476 et seq. possible causes of, 486 et seq. of matter in general, 496 et seq.
- Dissipation of charge in caves and cellars, 514 et seq. in closed vessels, 531 effect of pressure and nature of gas on, 534 et seq. effect of material of vessel on, 536 et seq.
- Dolezalek electrometer, construction of, 94 et seq.
- Dorn charge carried by β rays, 122 electrostatic deflection of β rays from radium, 124 discovery of radium emanation, 246 effect of moisture on emanating power of thorium, 255 electrolysis of radium solution, 313 loss of weight of radium, 474 radium emanation in springs, 513
- Dreyer and Salomonsen coloration of quartz by radium rays, 213
- Dunston analysis of thorianite, 486
- Durack ionization by collision of electrons of great velocity, 171
- Dust effect of, on recombination of ions, 42 effect of, on distribution of excited activity, 305
- Earth amount of radium in, 493 et seq. age of, 496 excited activity deposited on, 504 activity concentrated on peaks of, 504 emanation from, 507 very penetrating radiation from, 520
- Ebert condensation of emanation from the earth, 510 apparatus for determining number of ions per c.c. in air, 527 velocity of ions in air, 528
Table of Contents
INDEX.
542