None
Meyer (E.) structure of 7 rays, 291 Meyer (St.) phosphorescence in kunzite, 301 Meyer (St.) and Hess heating effect of radium, 571 Meyer (St.) and Mache total ionisation due to one curie of emanation, 502 Meyer and Regener probability variation of a particles, 187 Meyer (St.) and v. Schweidler absorption of a rays, 146 magnetic deflection of ft rays, 193 changes of activity in uranium, 453 analysis of radio-lead, 511 , period of radium D, 512 period of polonium, 515 period of actinium B, 525 separation of actinium C by volatili- sation, 526 residual activity on bodies exposed to actinium emanation, 527 Meyer (G.) and Himstedt luminosity of air due to a rays, 303 Millikan measurement of charge on ion, 52 Minerals activity of uranium and thorium, 13 separation of radium from uranium, 14 active substances present in uranium, 444 constancy of ratio of radium to uranium in, 446, 460 deficiency of radium in some uranium, 463 production of helium by uranium and thorium, 560 age of radio-active, 562, 598 E. R.-A. Minerals (cont.) amount of helium in uranium and thorium, 564 heating effect of uranium, 583 final transformation products of radio-active, 596 amount of lead in radio-active, 597 Mitchell radio-active equilibria, 431 Mobility of ions, 41 et seq. difference in, for positive and negative ions, 42, 44 Molecules number of, per c.c. of gas, 140 Moore and Schlundt methods of separation of uranium X, 453 separation of thorium X, 544 Moseley charge carried by ft rays from radium, 204 number of ft rays from radium B and radium C, 611 number of 7 rays per ft ray, 614 Moseley and Fajans see Fajans and Moseley Moseley and Makower see Makower and Moseley Moseley and Kobinson total ionisation produced by ft and 7 rays, 230, 295, 579 escape of helium from minerals by grinding, 563 Moulin saturation with a rays, 33 velocity of expulsion of delta rays, 171 radium collector, 324 Nagaoka structure of the atom, 620 Neon possible transformation product of radium emanation, 321 Nishikawa, Kinoshita and Ono theory of collection of active matter from atmosphere, 628 Nomenclature of radio-active substances, 23 et seq. origin of, for radiations, 115 change in, for active deposits, 524, 534 Nuttall and Geiger see Geiger and Nuttall Occlusion of emanation in thorium and radium, 359, 361 44 690 INDEX Ono, Kinoshita and Nishikawa theory of collection of active matter from atmosphere, 628 Owens effect of smoke on recombination, 41 absorption of a rays, 146 on thorium emanation, 348 Ozone production of, by radium rays, 314 Paschen apparent charge carried by y rays, 272 attempt to deflect 7 rays by a mag- netic field, 286 velocity distribution of /3 rays, 251 Peck and Willows effect of radium rays on spark, 322 Pegram electrolysis of active deposit, 409 electrolysis of active deposit of thorium, 537 Pegram and Webb heating effect of thorium, 583 Penetrating power comparison of, for a, /3 and 7 rays, 117 of |8 rays, 223 variation of, with energy of /3 par- ticle, 239 of 7 rays, 258 et seq. Perkins diffusion of radium emanation, 386 Perrin measurement of charge on ion, 52 charge carried by cathode rays, 76 structure of the atom, 410 Petavel and Eutherford effect of high temperature and pres- sure on decay of emanation, 505 Petterson heating effect of /3 rays from radium, 578 Phillips effect of temperature on recombina- tion, 41 effect of temperature on mobility of ions, 46 Phillips (C. E.) conducting glass fibres, 94 Phosphorescence ,of uranium salts, 7 due to radium rays, 296 of zinc sulphide, 297 of barium platinocyanide, willemite and kunzite, 298 of diamond, 299 effect of bombardment of a particles on, 300 decay of, for willemite and zinc sul- phide, 301 Phosphorescence (cont.) spectrum of, shown by radium, 302 spectrum of, shown by actinium, 302 production of, by heat (thermo-lumin- escence), 304 Phosphorus discharge by, 5 Photographic action of a rays from thick layers, 143 of a, j8 and 7 rays, 305 produced by one a particle, 306 Photographic method use of, in radio-activity, 87 application of, to deflection of j3 rays, 194 decrease of velocity of /3 rays by, 244 records by, of trails of a and /3 par- ticles, 663 registration of a particles by, 664 Physical actions of radium rays on spark, 322 on electrodeless discharge, 323 on resistance of selenium, 323 on conductivity of radium solutions, 323 on contact difference of potential, 323 equalization of potential, 324 on resistance of liquid and solid dielectrics, 324 Physiological actions of radium rays, 327 Piezo-electrique of quartz, 104 et seq. Pirret (Ruth) and Soddy ratio of radium to uranium in mine- rals, 463 Pohl luminosity of air due to a rays, 303 Pohl and Franck mobility of ions in helium, 45 Pollock large ions in the atmosphere, 638 Polonium discovery and properties of, 14, 20 connection with radio-tellurium, 20, 515 luminosity of air surrounding, 304 decomposition of water by, 318 connection of, with radium F, 515 chemical properties of, 516 amount of, in uranium minerals, 517 spectrum of, 517 possible transformation of, into lead, 517 heating effect of, 586 Poole heating effect of uranium and thorium minerals, 584 INDEX 691 Potassium discovery of activity of, 12 radio-activity of, 587 absorption of 8 rays from, 588 effect of conditions on activity of, 589 Precht and Range flame spectrum of radium, 471 heating effect of radium, 569 Pressure effect of, on mobility of ion, 46 effect of, on current through gases, 60 effect of, on ionisation due to y rays, 293 effect of, in distribution of active deposit, 401 vapour for radium emanation, 484 effect of, on y ray activity of radium, 505 Probability variations in emission of 8 particles, 186 et seq. variation in number emitted in given interval, 189 variation in ionisation due to y rays, 291 bearing of, on law of transformation, 419 Products final products of disintegration, 596 tables and properties of, 668 Przibram mobility of ions in vapours, 45 condensation of vapours round ions, 50 Pulse theory of X rays, 83 connection of, with y rays, 287 distribution of energy in, for y rays, 288 Quartz piezo-electrique, 104 et seq. effect of radium rays on, 308 Quinine sulphate discharge by, 6 Eadiation discovery of, from uranium, 7 constancy of, from uranium, 8 theories of, 80 of energy, from moving electron, 82 secondary, accompanying o rays, 170 recoil, 174 et seq. secondary, accompanying 8 rays, 204 from uranium, 447 from uranium X, 452 from uranium Y, 455 from ionium, 457 from radium, 474 Eadiation (cont.) from radium A, B, C, 489 from radium D, E, F, 508 from actinium products, 531 penetrating from earth and atmo- sphere, 594, 634 Eadio-actinium discovery and properties of, 529 rise and decay curves due to, 530 chemical properties of, 533 Eadio-active definition of term, 4 Eadio-lead discovery of, 21 connection with radium D, 21, 511 radio-active constituents of, 510 Eadio-tellurium separation of, 20 connection with polonium, 21 connection of, with radium F, 515 separation of, 516 Eadio- thorium discovery of, 11 separation and properties of, 544 radiations from, 545 growth of, from meso-thorium, 549 separation of, from meso-thorium, 551 Eadium discovery of, 12 et seq. separation of, 14 et seq. amount of, in minerals, 16 radiations from, 17 number of a particles emitted by, 132 groups of a rays present in, 150 clock, 199 number of 8 particles emitted by, 202 et seq. absorption of 8 rays from, in air, 229 distribution with velocity of 8 rays from, 251 velocity of groups of 8 rays from, 254 absorption of y rays from, 258 luminosity of compounds of, 302 spectrum of light emitted by, 303 chemical actions produced by radia- tions from, 314 decomposition of water by, 317 effect of radiations of, on spark, 322 effect of, on resistance of selenium, 323 use of, as potential equaliser, 324 effect of radiations from, on conduc- tivity of dielectrics, 324 motion of. velocity of, 175 separation of active substances by, 176 distance traversed in gases during, 176 velocity and mass of atoms liberated by, 177 use of, to determine atomic weights, 178 ionisation due to atoms liberated by, 179 range of atoms liberated by, 403 Eecombination of atoms of active deposit with ions, 400 Eecombination of ions 27, 38 theory of initial (Bragg), 33 coefficient of, 41 effect of pressure and temperature on, 41 effect of dust on, 41 Eeflection apparent for /3 rays, 212 Eegener * difficulty of saturation with a rays, 35 measurement of charge on a particle, 52, 137 scintillations produced by /3 particle, 133 counting of scintillations, 133 44—3 694 INDEX Eegener (cont.) decrease of number of a particles with distance, 156 scintillations in the diamond, 299 period of polonium, 515 Eeinganum effect of electric field on range of a particle, 165 photographic trail of a particle, 307 Eetardation of a particle, 141 law of, 145 of /3 particles in traversing matter, 240 Kicharz and Helmholtz actions of ions on steam jet, 47 Eighi scattering of /3 rays, 215 Einger and Jorissen action of (3 rays on hydrogen and chlorine, 316 Eitzel separation of uranium X by charcoal, 454, 601 Eobinson and Moseley see Moseley and Eobinson Eobinson (H.) and Eutherford heating effect of radium and its pro- ducts, 576, 577 heating effect of ft and 7 rays from radium, 580 Eocks amount of radium in, 644 amount of thorium in, 649 Eontgen rays discovery of, 1 theories of nature of, 83 et seq. Eoss and McCoy activity of thorium minerals, 546 Eossi and Eussell spectrum of ionium, 467 Eossignol and Gimingham decay of thorium emanation, 351 Eoyds spectrum of radium emanation, 483 Eoyds and Eutherford nature of a particle, 137 action of emanation on water, 321 spectrum of radium emanation, 482 Eubidium radio-activity of, 12, 587 absorption of j8 rays from, 589 Eudge colouration of glass by radium rays, 307 Euer and Levin photographic action of potassium rays, 588 Eumelin decay of radium emanation, 352 Eunge arid Precht see Precht and Eunge Euss diffusion of thorium emanation, 388 distribution of active deposit of acti- nium, 399 distribution of active deposit at low pressures, 402 Euss and Makower see Makower and Euss Eussell effect of temperature on decay of products of radium, 503 effect of gases on volatilisation of radium C, 507 Eussell and Marckwald ratio of radium to uranium in mine- rals, 463 Eussell and Eossi spectrum of ionium, 467 Eussell and Soddy absorption of 7 rays from radium, 259 correction for absorption using wide cone of 7 rays, 261 absorption of 7 rays from radio- active substances, 267 period of uranium X, 452 separation of uranium X, 453 Eussell and Soddy (Mr and Mrs) absorption of 7 rays by lead, 260 Saake activity of atmosphere at high alti- tudes, 631 Sackur decay of radium emanation, 352 Sackur and Hahn see Hahn and Sackur Salomonsen and Dreyer effect of radium rays on quartz, 308 Sanderson amount of radium and thorium ema- nation in air drawn from the soil, 643 Satterly absorption of radium emanation by charcoal, 380 amount of radium in potassium salts, 589 amount of radium emanation in atmosphere, 633 Saturation current meaning of, 29 difficulty of obtaining with a rays, 32 et seq. ' Scattering of a rays laws of, 180 et seq. through large angles, 183 theory of, 184 single and compound, 186 INDEX 695 Scattering of 8 rays effect of, on distribution, 215 amount of, by different materials, 217 variation of, with velocity, 217 by transmission, 218 by thin sheets of matter, 219 theories of, 220 Scattering of 7 rays, 279 variation of amount of, with material and angle, 281 Schenke radium emanation in thermal springs, 641 Schlundt and Moore see Moore and Schlundt Schmidt (G. C.) discovery of activity of thorium, 10 •Schmidt (H. W.) use of quartz fibre in electroscope, 94 reflected 8 rays, 216 absorption of 8 rays, 224 coefficients of absorption of 8 rays, 225 absorption of 8 rays by liquids, 228 theory of absorption of 8 rays, 231 velocity of 8 rays from radium E and uranium X, 238 distribution of 8 rays, 314 recombination of atoms of active deposit, 400 8 rays from radium B, 488 decay of active deposit of radium, 492 effect of 8 rays from radium B on rise curve, 493 effect of temperature on decay of products of radium, 503 Schmidt (H. W.) and Cermak effect of temperature on decay pro- ducts of radium, 503 Schrader effect of gases on volatilisation of active deposit, 506, 600 Schuster measurement of e/m for cathode rays, 78 pulse theory of X rays, 83 effect of pressure on 7 ray activity. of radium, 505 v. Schweidler probability variations in transforma- tions, 187 v. Schweidler and Bohm-Wendt conductivity of oils under radium rays, 326 v. Schweidler and Hess heating effect of radium, 571 v. Schweidler and Mache velocity of ions in atmosphere, 638 v. discovery of thorium X, 332 decay of thorium X, 333 decay and rise of uranium X, 335 decay of radium emanation, 352 effect of conditions on emanating power of thorium, 358 condensation of thorium and radium emanations. 364 temperature of condensation of radium emanation, 366 development of disintegration theory, 413 period of uranium X, 452 origin of helium in radio-active substances, 555 Soil radio-activity of, 640 presence of radium and thorium emanations in, 643 Spectrum of ionium, 467 of radium, 470 of radium emanation, 482 of polonium, 517 Spinthariscope, 133 Standards of ionisation, 111 of radium, 660 et seq. Stark (J.) nature of 7 rays, 290 theory of successive changes, 418 Stark and Giesel luminosity of air due to rays from polonium, 304 Starke (H.) determination of ejm for cathode rays, 208 production of 7 rays by 0 rays, 282 Steele and Grant micro-balance, 481 Stokes terminal velocity of small sphere in air, 51 pulse theory of X rays, 83 Stoney (Johnstone) origin of name "electron," 79 Stopping power definition of, for a particle, 165 law of, 165 variation of, with velocity, 168 Stormer theory of aurora, 654 Strauss and Hofmann discovery of radio-lead, 21 Stromholm and Svedberg chemical properties of thorium X and actinium X, 533, 544 Strong activity of potassium, 588 Strutt conductivity of gases, 62 nature of a rays, 119 radium clock, 199 absorption of 8 rays from radium ,. 227 luminosity of autunite, 302 constancy of radium to uranium in minerals, 460 rate of production of helium by uranium and thorium minerals, 561 escape of helium from thorianite, 563- amount of helium in radio-active minerals, 564 origin of the helium in beryl, 565 age of geological strata, 566 amount of helium in specimens of zircon, 566 amount of helium in saline minerals, 568 radio-activity of ordinary materials^ 592 radium, emanation in hot springs,. 641 amount of radium in rocks, 644 radium in meteorites, 653 Sun presence of radium in, 654 duration of heat of, 655 Svedberg and Stromholm see Stromholm and Svedberg Swinne relation between range of a particle and period of transformation, 609> Szilard concentration of radium D, 511 Taylor ionisation of a particle, 65 variation of ionisation with range for gases, 154 variation of stopping power with velocity, 168 Temperature effect of, on decay of radium ema- nation, 355 effect of, on escape of thorium ema- nation, 359 effect of, on escape of radium ema- nation, 361 effect of, on condensation of emana- tions, 366 effect of, on active deposits, 409 effect of, on volatility of active deposit of radium, 503 independence of rate of transforma- tion on, 503 INDEX 697 Temperature (cont.) of volatilisation of radium products in different gases, 506 Thermo-luminescence, 304 Thomson (Sir J. J.) difference between positive and nega- tive ions, 49 measurement of charge on ion, 51 electrical mass of a charged body, 71 charge carried by cathode rays, 76 electrostatic deflection of cathode rays, 77 measure of e/m for cathode stream, 78 •canal rays, 81 pulse theory of X rays, 83 distribution of energy in pulse theory, 84 emission of delta rays, 135 properties of delta rays, 170 theory of scattering of /3 rays, 220 origin of heat energy of radium, 412 structure of the atom, 617 number of electrons in atoms, 618 radio-activity of tap water, 641 Thomson (J. J.) and Kutherford theory of ionisation, 26 Thorianite production of helium by, 561 age of, 562 escape of helium from, 563 Thorium discovery of activity of, 10 nature of radiations from, 10 emanation from, 10 changes in activity of, 11 calculation of variation of activity of commercial preparations, 440, 546 transformations of, 534 et seq. number of a particles emitted by, 551 period of, 551 series of transformations of, 552 rate of production of helium by, 560 heating effect of, 583 end product of, 599 relation between range and period of transformations of, 607 distribution of, in rocks, 649 Thorium emanation discovery and properties of, 348 decay of, 350 radiations from, 357 effect of conditions on escape of, 358 condensation of, 364 absorption of, by liquids, 377 absorption of, by solids, 379 diffusion of, 387 number of a particles expelled by, 395 transformation of, 534 presence of, in atmosphere, 626 emission of, by soil, 641 Thorium emanation (cont.} emission of, by sediment, 642 measurement of amount of, in soil, 643 Thorium A discovery and properties of, 396 period and properties of, 534 Thorium B period and properties of, 535 volatilisation of, 537 electrolysis, 537 radiations from, 538 electro-chemical properties of, 603 Thorium C separation and properties of, 535 volatilisation of, 537 separation of, on nickel plate, 538 analysis of a radiations from, 539 complex nature of, 539 modes of disintegration of, 541 electro-chemical properties of, 603 Thorium GI component product of thorium C, 540 Thorium C2 component product of thorium C, 540 Thorium D absorption of 7 rays from, 268 proportion of 7 rays to /3 rays, 271 separation and properties of, 542 radiations from, 542 electro-chemical properties of, 603 Thorium X discovery of, 333 decay and rise of, 333 separation and properties of, 543 radiations from, 543 chemical properties of, 544 electro-chemical properties of, 603 Thorpe (Sir T. E.) atomic weight of radium, 472 Townsend ionisation by collision, 36 coefficient of recombination of ions, 40 diffusion of ions in gases, 53 et seq. proof that charge on ion equals charge carried by hydrogen atom in elec- trolysis, 55 compensation method of measure- ment, 103 Transformation products of, 22 et seq. decay and exponential law of, 22 of matter by radiations, 320 meaning of exponential law of, 341 theory of, 344, 410 et seq. development of theory of, 413 theory for one, 419 theory of successive, 420 rayless, 433 analogies between series of, 605 698 INDEX Transformation (cont.) relation between range and period of, 607 origin of 8 and y rays in, 611 et seq. mode of, 620 causes of, 621 irreversible character of, 623 Traubenberg absorption of radium emanation by liquids, 375 Tuomikoski absorption of y rays, 259 Ulrich and Haitinger separation of radium, 16 Ultra-violet light discharge by, 5 Uranium discovery of activity of, 6 phosphorescence of salts of, 7 activity of compounds of, 13 use of, as ionisation standard, 111 absorption of a rays from, 146 range of a rays from, 163 absorption of 8 rays in, 229 absorption of y rays from, 264, 268 proportion of y rays to 8 rays from, 271 luminosity of nitrate of, 302 connection with ionium and radium, 444 activity of minerals containing, 445 relative activity of products of, in minerals, 446 complexity of, 447 presence of two groups of a rays in, 449 period of, 450 effect of periods of two components on relative activity of, 451 connection between radium and, 460 production of radium in, 465 series of products of, 468 rate of production of helium by, 560 heating effect of, 583 end product of, 597 relation between range and period of transformation of, 607 amount of, in earth, 650 Uranium 1, 449, 468 (see Uranium) Uranium 2, 449, 468 (see Uranium) Uranium X absorption of y rays from, 264, 268 proportion of y rays to (3 rays, 271 discovery of, 330 methods of separation of, 331 decay of, 331 decay and rise of, 335 period of, 452 radiations from, 452 Uranium X (cont.) methods of separation of, 453 chemical properties of, 454, 603 Uranium Y discovery and properties of, 454 Usher action of a rays on hydrogen and! nitrogen, 316 rate of decomposition of water by actinium and radium, 318 Valency change of, in a ray transformations, 606 Varley discovery of cathode rays, 76 Vegard theory of aurora, 654 Velocity of ions, 27 et seq. of a particles, 123, 128 variation of absorption of /3 rays withr 238 decrease of, for 8 rays in traversing matter, 240 variation of ionisation of 8 rays withr 245 distribution with, of the 8 rays, 250 of homogeneous groups of 8 rays, 254 of atoms of active deposit, 407 of ions in atmosphere, 638 Villard discovery of y rays, 257 Volatilisation of radium products, 504, 505 effect of gases on, 506 Volatility separation of products by, 600 Waklhoff production of burns by radium, 327 Wallstabe diffusion of radium emanation in liquids, 390 Walter luminosity of air due to a rays, 303 v. Wartburg and v. Lerch volatility of thorium D, 542 Water decomposition of, by radiation, 317 et seq. Watson spectrum of radium emanation, 483 atomic weight of helium, 554 Webb and Pegram heating effect of thorium, 583 Wellisch mobility of ions, 45 mobility of ions in gaseous mixtures, 46 INDEX 699 Wellisch (cont.) theory of movement of ions in gases, 57 Wellisch and Bronson charge on active deposit, 399 Welsbach (Auer v.) attempts to separate ionium and thorium, 457 separation of actinium, 520 Wertenstein distance traversed by recoil atoms, 176 ionisation due to recoil atoms, 179 range of recoil atoms, 405 "Wheeler and Bumstead see Bumstead and "Wheeler Wheelock saturation with a rays, 35 Whiddington characteristic X rays, 85 variation of absorption of 8 rays with speed, 239 retardation of cathode rays, 244 velocity of electron to excite character- istic rays, 292 Wiechert velocity of cathode rays, 79 pulse theory of X rays, 83 Wiedemann thermo-luminescence due to 8 rays, 305 Wiedemann and Schmidt thermo-luminescence, 304 Wien canal rays, 81 charge carried by 8 rays of radium, 201 Wigger absorption of 7 rays, 259 Willemite luminosity of, 298 decay of luminosity of, 300, 301 Willows and Peck effect of radium rays on spark, 322 Wilson (C. T. K.) condensation of water on ions, 47 et seq. difference between positive and negative ions, 49 electroscope constructed by, 92 tilted electroscope, 95 detection of single a particle, 134 natural ionisation of air, 591, 624 variation of natural ionisation with pressure and nature of gas, 592 activity of rain and snow, 627 record of trails of a and 8 particles, 663 Wilson (H. A.) measurement of charge on ion, 51 Wilson (W.) exponential law of absorption of 8 rays, 211 absorption of homogeneous B rays, 235 retardation of 8 rays in traversing matter, 241 variation of ionisation of 8 particles with speed, 248 velocity distribution of 8 rays, 251 variation of absorption of 7 rays with temperature, 293 variation of ionisation of 7 rays with pressure, 293 thorium emanation in atmosphere, 626 Wilson (W.) and Gray (J. A.) complex nature of B rays from radium E, 238 Wilson (W.) and Kovarik variation of scattering of 8 rays with velocity, 217 Wolfl, Hofmann and Gonder constituents of radio-lead, 510 Wolfl and Hofmann concentration of radium D, 511 Wood (E. W.) duration of scintillations, 300 Wood and Campbell see Campbell and Wood Wright rate of leak of screened electroscope, 594 absence of penetrating radiation over water, 636 Wright and Simpson see Simpson and Wright Wulf quartz fibre electroscope, 96 variation of penetrating radiation with altitude, 636 Zeeman effect of magnetic field on spectrum lines, 80 Zeleny mobility of ions, 42, 44 potential gradient, 65 Zinc sulphide scintillating property of, 297 duration of scintillations in, 300 effect of continued bombardment on, 300 theory of decay of luminosity of, 301 Zircon amount of helium and radium in, 566 CambriUge : PRINTED BY JOHN CLAY, M.A. AT THE UNIVERSITY PRESS. UNIVERSITY OF CALIFORNIA MEDICAL SCHOOL LIBRARY THXS DATE t0 a fine of 50« NOV 2 n JUN 2 1 19461. 