Page:Radio-activity.djvu/596

 effect of temperature on active deposit of, 390 relative activity due to products of, 395 active deposit of slow transformation, 397 physical and chemical properties of radium D, E and F, 398 et seq.  effect of temperature on active deposit of slow change, 401   separation of radium F by bismuth, 402   products of, 402 et seq.   rate of transformation of radium D, 404 et seq.   variation of the activity of the active deposit over long periods of time, 407   amounts of radium D, E and F in old radium, 408   variation of activity of, with time, 409   products of in pitchblende, 410   origin of radio-tellurium, 411   origin of polonium, 411, 412   origin of radio-lead, 413   temporary activity of inactive matter separated from pitchblende, 415 et seq.   heat emission of, 419 et seq.   heat emission of emanation from, 420, 431   heating effects due to products of, 433   theories of radio-activity of, 437 et seq.   discussion of theories of radio-activity of, 441 et seq.   energy of radiations, not derived from external source, 442 et seq.   theory of radio-active change, 444 et seq.   list of active products of, 449   amount of products of, 452   rate of change of, 457   life of radium, 457   origin of, 459 et seq.   production of, by uranium, 459 et seq.   amount of in 1 gram of uranium, 461   amount of, in minerals, 461   radio-activity of, independent of concentration, 466 et seq.   disappearance of, 467   life of, independent of concentration, 468   conservation of radio-activity of, 469 et seq.   loss of weight of, 473   experiments to determine loss of weight of, 474   total emission of energy from 1 gram of, 474 et seq.   production of helium from, 476   helium, disintegration product of, 479 et seq.   amount of helium from, 480   possible causes of disintegration of, 486 et seq.   amount of, to account for heat of sun, 491   possible connection of with heat of sun, 491   possible connection of with heat of earth, 493   probable amount of, in earth, 495   amount of, in atmosphere, 495, 524   presence of, in atmosphere, 521 et seq.

Radium A decay curve of, 378 radiation from, 381 effect of, on activity curves, 386 et seq. connection with later changes, 392 activity supplied by, 393

Radium B absence of rays in, 381 effect of, on activity curves, 381 et seq. effect of temperature on, 390 volatility of, 390 absence of heating effect of, 433 nature of rayless change in, 454, 552

Radium C radiations from, 381 analysis of β ray curves of, 381 et seq. analysis of α ray curves of, 386 et seq. effect of temperature on, 390 activity supplied by, 394 et seq. heating effect of, 425 use of, as a source of β rays, 435 explosive nature of change in, 456 magnetic deflection of rays from, 543 velocity and value of e/m for rays from, 544

Radium D origin of name of, 376 connection of, with active deposit, 403 period of transformation of, 406 effect of, on variation of activity, 407 presence in old radium, 408 effect of, on activity of old radium, 409 presence in pitchblende, 410 connection with radio-lead, 413 amount of, in 1 ton of uranium, 454

Radium E effect of temperature on, 401 connection of, with β ray activity active deposit, 403, 400