INDEX. 



559 



Phosphoric acid, on a new method of 

 estimating, 192. 



Picard (M.) on the presence of urea 

 in the blood, 537. 



Plant (J.) on the Keuper sandstone 

 and its fossils, 71- 



Plateau (M. T.) on the recent theories 

 of the constitution of jets of liquid 

 issuing from circular orifices, 286". 



Platinum, on a new compound of, 301. 



Potassium, on the specific heat and 

 atomic weight of, 500. 



Powell (Rev. B.) on the demonstra- 

 tion of Fresnel's formulae for re- 

 flected and refracted light, and their 

 applications, 1, 104, 266. 



Prestwich (J.) on the correlation of 

 the middle eocene tertiaries of Eng- 

 land, France, and Belgium, 153. 



Projectiles, on a construction for the 

 range of, 112. 



Ptychotis Ajowan, on the oil of, 63. 



Quantics, memoir on, 477- 



Quaternions, on extensions of the,446. 



Railway train, on the measurement of 

 the speed of a, 486. 



Rainey (G.) on the structure and de- 

 velopment of the Cysticercus cellu- 

 loscc, 141. 



Rankine (W. J. M.) on heat as the 

 equivalent of work, 103 ; on the 

 mathematical theory of the sta- 

 bility of earthwork and masonry, 

 468. 



•Regnault (M.V.) on the specific heat 

 of some simple bodies, and on the 

 isomeric modifications of selenium, 

 489. 



Reissig (M.) on a new method of esti- 

 mating phosphoric acid, 192. 



Rhodium, on the specific heat and 

 atomic weight of, 493. 



Riess (Dr. P.) on a law of electrical 

 hea 322, 553. 



Ritter (M.) on thioformic and aniso'inic 

 acids, 56 ; on the aldehydes, 57. 



Rose (Prof. H.) on boracic aether, 300. 



Rotatory motion, observations on,477. 



Royal Society, proceedings of the, 59, 

 141, 226, 305, 387, 466, 539. 



Rubian, action of alkalies and oxygen 

 on, 200 -, action of chlorine on, 270. 



Sabine (General) on the larger mag- 

 netic disturbances, 231. 



Salicylic acid, on new compounds of, 

 192. 



SalmonidcB, on the vitality of the ova 

 of the, 305. 



Salter (J. W.) on a new genus of 

 Cephalopoda, 72 ; on the fossils of 

 the chalk-flints and greensand of 

 Aberdeenshire, 152. 



Sand, on a peculiar power possessed 

 by, of removing matter from solu- 

 tion in water, 23. 



Sawkins (J. G.) on the movement of 

 land in the South Sea Islands, 73. 



Scheerer (Prof.) on the detection of 

 several organic acids in mineral 

 waters, 538. 



Scheutz's calculating machine, ob- 

 servations on, 225. 



Schmidt (Prof.) on the boracic acid 

 fumaroles of Tuscany, 193. 



Schonbein (Prof.) on the oxidation 

 of the constituents of ammonia by 

 porous media, and on nitrification, 

 457. 



Schunck (Dr. E.) on rubian and its 

 products of decomposition, 200, 

 270. 



Secchi (P. A.) on a drawing of the 

 lunar spot Copernicus, 474. 



Selenium, on the isomeric modifica- 

 tions of, 489. 



Silicium and titanium compounds, on 

 the formulae of, 190. 



Silicon,on an allotropic condition of,54 . 



Silurian rocks of Wigtonshire, on the, 

 68. 



Slaty cleavage, on the theory of the 

 origin of, 35, 127, 197, 409. 



Sodium, on the explosive action of, 

 on water, 78 ; on the specific heat 

 and atomic weight of, 497. 



Sorby (H. C.) on the theory of the 

 origin of slaty cleavage, 127. 



Sphygmoscope, description of a new, 

 387. 



Spratt (Capt.) on the geology of 

 Varna, 150. 



Steam-engine, on the application of 

 the mechanical theory of heat to 

 the, 241, 338, 385, 426, 463. 



Stenhouse (Dr. J.) on certain vege- 

 table products from India, 59. 



Stereognathus ooliticus, observations 

 on the, 482. 



Stevelly (Dr. J.) on the doctrine of 

 parallel lines, 220, 375. 



Stokes (Prof. G. G.) on a theory of 

 the composition of colours, 421. 



