440 



powers by, i. 90 ; on the laws which 

 regulate the polarization of light 

 by, ii. 14; reflexion of light produ- 

 cing polarization, ii. 394. 

 Refraction : atmospherical, on double 

 images caused by, i. 16, 371, 500. 

 ii. 296, 308; horizontal, on the quan- 

 tity of, i. 100; some remarks upon, 

 with the co-latitude of the Dublin 

 Observatory, i. 374; on astronomi- 

 cal refractions, ii. 200, 207 ; on the 

 laws of the polarization of light by, 

 ii. 394. 



, double : on its production 



by pressure, ii. 7, 389 ; on the laws 

 of in crystallized bodies, ii. 92 ; 

 doubly-refracting crystals, on the 

 laws which regulate the absorption 

 of polarized light by, ii. 104; two 

 modes of conducting observations on, 

 ii. 122. 



Refractive and dispersive powers, 

 method of examining by prismatic 

 reflexion, i. 90. 



Refrangibility of radiant heat, i. 20 ; 



of the invisible rays of the sun, i. 22. 



Register-pyrometer, Mr. Daniell's, ii. 



404. 



Relistian tin mine, account of, i. 275. 

 Rennell (J.) on the effect of westerly 

 winds in raising the level of the 

 British Channel, i. 344 ; on the cur- 

 rent to the westward of the Scilly 

 Islands, ii. 17. 

 Rennie (G.), experiments on the 

 strength of materials, ii. 87; experi- 

 ments on the friction and abrasion 

 of the surfaces of solids, ii. 364. 

 Resistance of fluids to bodies passing 



through them, ii. 327. 

 Respiration : Mr. W. Allen and Mr. 

 W. H. Pepys on, i. 345. ii. 375 ; 

 changes produced in atmospheric air 

 and oxygen gas by, i. 305 ; inter- 

 ruption of the circulation owing to 

 the stoppage of, i. 389; on the struc- 

 ture of the organs of in the lamprey, 

 myxine, Aphrodita aculeata, and the 

 leech, ii. 23 ; artificial, ii. 121; on 

 the nerves of, ii. 153, 171; on the 

 organs of, in the gryllotalpa, ii. 237 ; 

 of birds, experiments on, ii. 375 ; 

 on the structure of the cells of the 

 human lungs, ii. 303. 

 Rete mucosum, black, of the negro, on 

 the use of, ii. 135. 



Reversions, contingent, depending up- 

 on three lives, i. 4. 



Rhea americuna, i. 450. 



Rhinoceros : anatomical description 

 of, i. 41 ; account of some fossil re- 

 mains of the, ii. 66, 142; two-horned, 

 account of the skeleton of, ii. 147 ; 

 African, ii. 157. 



Rhodium, a new metal, i. 162. 



Richardson (Dr. W.) on the alterations 

 in the structure of the rocks in Derry 

 and Antrim, i. 300. 



Riding and carriage exercise, advan- 

 tages derived from, i. 349. 



Ritchie (Rev. W.) on a new photome- 

 ter to determine the relative inten- 

 sities of artificial light, &c. ii. 231 ; 

 on a new form of the differential 

 thermometer, ii. 309 ; on the per- 

 meability of transparent screens of 

 extreme tenuity by radiant heat, ii. 

 310 ; on electric conduction, ii. 350; 

 on the electric and chemical theories 

 of galvanism, ii. 382 ; on the elas- 

 ticity of threads of glass, and appli- 

 cations of this property to torsion 

 balances, ii. 402. 

 River Jordan, analysis of the water 



of, i. 275. 



Robertson (Rev. Dr. A.), new demon- 

 stration of the binomial theorem, i. 

 239 ; on the precession of the equi- 

 noxes, i. 253 ; methods of calcu- 

 lating the excentric from the mean 

 anomaly of a planet, ii. 37 ; demon- 

 strations of Dr. Maskelyne's for- 

 mulae for finding the longitude and 

 latitude of a celestial object from its 

 right ascension and declination, and 

 for finding its right ascension and 

 declination from its longitude and 

 latitude, ii. 38. 



Robertson (J.) on the permanency of 

 the variation of the compass at Ja- 

 maica, i. 241. 



Rock crystal, account of a micrometer 

 made of, ii. 141 ; on the methods of 

 cutting for micrometers, ii. 124. 

 Rocks, alterations in the structure of 



in Derry and Antrim, i. 300. 

 Rodriguez (Don Joseph) on the mea- 

 surement of three degrees of the 

 meridian conducted in England by 

 Lieut-Col. W. Mudge, i. 435. 

 Roget (Dr. P. M.), new instrument for 

 performing the involution and evo- 



