INDEX 



79L 



X-rays and the atomic weight of, 

 408 ; on the superposition of 

 mechanical vibrations upon mag- 

 netization in, 468. 



Oldham (R.) on the constitution of 

 the interior of the earth, as revealed 

 by earthquakes, 786, 



Oscillations, on the forcing- of, by 

 disturbances of different frequen- 

 cies, 115 ; on determining 1 the 

 frequencies of slow electrical, 238; 

 on the Poulsen arc as a means of 

 obtaining continuous electrical, 

 254 ; on the superposition of elec- 

 tric, upon magnetization. 468 ; on 

 the stability of the steady state of 

 forced, 767. 



Owen (G.) on condensation nuclei 

 produced by cooling gases to low 

 Temperatures, 528. 



Phosphorescence, on an abrupt limit 

 in the power of the positive rays 

 to produce, 614. 



Photanthistan, on the, 428. 



Photo-electric effects, on the influ- 

 ence of temperature upon, 188; 

 on the, of ultra-violet light, 297. 



Photometer, on a cosine flicker, 644. 



Pitch, on the sensitiveness of the 

 ear to, 596. 



Planets, on a general method for 

 evaluating the surface-temperature 

 -of the, 161, 749. 



Pochin (E. A. N.), experimental 

 mathematics, 895. 



Positive rays, on an abrupt limit of 

 distance in the power of the, to 

 produce phosphorescence, 614. 



Poulsen arc, on the, as a means of 

 obtaining continuous electrical 

 oscillations, 254. 



Poynting (Prof. J. H.) on the surface 

 temperature of the planets, and the 

 effect of day and night on the 

 temperature of the earth, 749. 



Prescott (J.) on the figure of the 

 earth, 482. 



Preston (Dr. S. T.) on questions con- 

 nected with astronomical physics, 

 265. 



Radiation, on secondary, from a plate 

 exposed to rays from radium, 176 ; 

 from hot bodies, on the electrical 

 origin of the, 217 ; on secondary 

 Rontgen, in air, 604. 



Radiations, on the properties and 

 natures of various electric, 429. 



Radioactivity of radium, on the 

 explanation of the, 210;. of lead 

 and other metals, on the, 760. 



Radium, on secondary radiation 

 from a plate exposed to rays from, 

 176 ; on the radioactivity of, 210; 

 on the amount of, in rocks in the 

 neighbourhood of Montreal, 281 ; 

 on the relation between uranium 

 and. 272 ; on the rate of decay of 

 the active deposit from, 404 ; on 

 the rate of transformation of the 

 emanation from, 550 ; on the 

 amount of emanation from, in 

 the atmosphere, 724 ; on the pro- 

 duction and origin of, 733. 



Raman (O. V.) on the curvature 

 method of determining the surface- 

 tension of liquids, 591. 



Rayleigh (Lord) on the remarkable 

 case of diffraction spectra de- 

 scribed by Prof. Wood, 60 ; on 

 the passage of sound through 

 narrow slits, 153; on the light 

 dispersed from fine lines ruled 

 upon reflecting surfaces or trans- 

 mitted by very narrow slits, 350 ; 

 on the relation of the sensitiveness 

 of the ear to pitch, 596. 



Reflexion, on Lloyd's fringes for 

 internal, 503. 



Richardson (Prof. 0. W.) on a 

 theory of the displacement of 

 spectral lines by pressure, 557. 



Rocks, on the amount of radium 

 present in, 281. 



Rontgen radiation, on secondary, in 

 air, 604 ; on the secondary, from 

 gases and vapours, 653. 



Rumelin (Dr. G.) on the rate of 

 transformation of the radium ema- 

 nation, 550. 



Russell (J.) on the superposition of 

 mechanical vibrations upon mag- 

 netization and conversely, in iron, 

 steel, and nickel, 468. 



Rutherford (Prof. E.) on the pro- 

 duction and origin of radium, 733. 



Sadler (C. A.) on secondary X-rays and 

 the atomic weight of nickel, 408. 



Schott (G. A.) on the radioactivity 

 of radium, 210. 



Searle (J. H. C.) on the effect of 

 rotatory inertia on the vibrations 

 of bars', 35. 



Slits, on the passage of sound 

 through narrow, 153 ; on the 



