43] 



VOLUMES XXI-XXX. 



479 



Radiometer for low pressures, 

 Dewar, 25, 258. 



— for observing- smaJl pressures, 

 Dessar, 27, 405. 



Radium, absorption of the 7-rays 

 by lead, Taomikoski, 28, 76. 



— a-particle from, Rutherford 

 and Geiger, 27, 262. 



— alpha-rays from, properties, 

 Rutherford, 21, 172; range, 

 Duane, 26, 464; retardation, 

 Taylor, 28, 357; ionization by, 

 Wheelock, 30, 233. 



— atomic weight, Jones, 21, 397; 

 Curie, 24, 439; Thorpe, 26, 91. 



— chemical action of penetrating 

 rays, Kernbaum, 28, 408. 



— condensation, Rutherford, 27, 

 487; in presence of water vapor, 

 Curie, 25, 145. 



— crystal photography, Walter, 

 21, 466. 



— emanation. Ashman, 26, 119; 

 Curie and Gleditsch. 26, 509; 

 Curie, 26, 510; Rutherford, 27, 

 185, 336. 



• action upon the elements of 



the carbon group, Ramsay and 

 Usher, 29, 80. 



— — in the atmosphere, Eve, 25, 

 147; 26, 577- 



— • — electric discharges, De- 



bierne. 28, 494. 

 — ■ emission of electricity from, 



Duane, 26, i. 



— heat evolved bj', von Schweid- 

 ler and Hess, 27, 83. 



— helium from, 27, 262. 



— life of, Boltwood, 25, 493. 



— liquid and solid. Gray and 

 Ramsay, 27, 485. 



— metallic. Curie, 30, 349; Curie 

 and Debierne, 30, 34". 



— molecular weight, Perkins, 25, 

 461. 



— in the earth, Strutt, 25, 346; in 

 tufa deposits, Schlundt, 26, S7S- 



— origin, Hahn, 25, 79; Ruther- 

 ford, 25, 147. 



— practical application, Baxter 

 and Tilley, 29, 188. 



• — production of, 29, 189; produc- 

 tion by actinium, Boltwood, 22, 

 537- 



— standard, 30, 416. 



— • radio-activity of the salts of, 

 Boltwood, 21, 409. 



— and thorium, relative activity. 

 Eve, 22, 477. 



Radium and uranium in radio- 

 active minerals, Rutherford and 

 Boltwood, 22, i; Eve, 22, 4; 

 Gleditsch, 29, 79. 



Raffety, C. W., Radio-activity, 27, 

 406. 



Raindrops, influence of thunder 

 on size of, Laine, 29, 190. 



Randall, D. L., ferric chloride in 

 the zinc reductor, 21, 128; titra- 

 tion of mercurous salts, 23, 137; 

 behavior of molybdic acicl, 24, 

 313-. 



Rankin, G. R., binary systems of 

 alumina with silica, etc., 28, 293. 



Ransome, F. L., Cripple Creek 

 gold deposits, 23, 466; apatitic 

 minette from Washington, 26, 

 337; bismite, 29, 173. 



Raymond, P. E., Chazy formation 

 and fauna, 22, 348; Upper De- 

 vonian fauna with Clymenia, 23, 

 116; age of the Tribes Hill for- 

 mation, 30, 344. 



Rays, alpha, anode, canal, 

 cathode, see Alpha-rays, etc. 



— of high penetrability, Wulf, 27, 

 405- 



— magnetic, etc., Righi, 28, TJ. 



— positive, Thomson, 26, 576; 

 Wien, 27, 84; 28, 555. 



Doppler effect in, Trow- 

 bridge, 27, 245. 



■ excitement by ultra-violet 



light, Dember, 28, 496. 



power to produce phosphor- 

 escence, Kunz, 24, 499. 



— ■ Rontgen, see Rontgen-rays. 



Read, H. L., determination of 

 chlorine, 28, 544. 



Read, T. T., re-formation of soda- 

 leucite, 21, 294. 



Reflection, positive changed to 

 negative through pressure, 

 Lummer and Sorge, 29, 264. 



Refraktionstafeln, de Ball, 22, 82. 



Refrigeration, Anderson, 25, 524. 



Reid, H. F., California earthquake 

 of 1906, 30, 287. 



Relay, telephone, J. Trowbridge, 

 21, 339; Jensen and Sieveking, 

 21, 173- 



Renshaw, G., Animal Romances, 



27, 193- 

 Reyer, E., Geologische Prinzi- 

 pienfragen, 26, 238; Kraft, 

 okonomische, etc., 27, 272; 29, 

 560. 



