560 



INDEX. 



Sulphur, on the allotropic conditions 

 of, 526. 



Sylvester (Prof. J. J.) on a construc- 

 tion for the range of projectiles, 112. 



Symonds (Rev. W. S.) on trap dykes, 

 73. 



Teeth, on the structure of the, 470. 



Tellurium, on the specific heat and 

 atomic weight of, 504. 



Thames water, on the composition of, 

 23,114. 



Thioformic acid, on the formation and 

 constitution of, 56. 



Thomson (Prof. W.) on the electro- 

 dynamic properties of metals, 393 ; 

 on the thermal efilects of fluids in 

 motion, 466; on a mathematical 

 theory of elasticity', 539. 



Thymole, onnewdenvativesfrom, 534. 



Tides, observations on the, 184. 



Titanium and silicium compounds, on 

 the formulae of the, 190, 232. 



Toluric acid, on the preparation and 

 properties of, 193. 



Tomes (J.) on the presence of fibrils 

 of soft tissue in the dentinal tubes, 

 470. 



Tyndall (Prof.) on the cleavage of 

 crystals and slate rocks, 35, 129; 

 on the polarity of the diamagnetic 

 force, 161. 



Ultramarine, artificial, on the consti- 

 tution of, 300. 



Unity, on a new system of roots of, 

 446. 



Urea, on the artificial production of, 

 194; on the production of, from 

 albumen, 537 ; on the presence of, 

 in the blood, 538. 



Velocities, on a direct method of esti- 

 mating, 397. 



Verdet (M.) on the optical properties 

 of transparent bodies submitted to 

 the action of magnetism, 483. 



Vogel (Dr. A.) on the behaviour of 

 iodide of silver towards ammonia, 

 157. 



Vohl (Dr.) on a triple sulphate of 

 magnesia, manganese and zinc, 304; 

 on a new saccharine matter from 

 Phaseolus vulgaris, ib. 



Voit (M.) on some benzoyle com- 

 pounds, 301. 



Waller (Dr. A.) on the organ of 

 vision, 148 ; on the vagus and 

 spinal accessory nerves, 472. 



Water, on the purification of, 23. 



Weald-denudation, observations on 

 the, 447. 



Wedgwood (H.) on a system of geo- 

 metry derived from an analysis of 

 our ideas of direction and position, 

 459. 



White lead, on the cleavage of com- 

 pressed, 157. 



Wilkens (M.) on artificial ultra- 

 marine, 300. 



Witt (H. M.) on a peculiar power 

 possessed by porous media of re- 

 moving matter from solution in 

 water, 23 ; on the variations in the 

 chemical composition of the Thames 

 water, 114. 



Wohler (Prof.) on an allotropic con- 

 dition of silicon, 54. 



Woods (Dr.) on the heat of chemi- 

 cal combinations, 65, 74, 233. 



Woodward (S. P.) on an Orthoceras 

 from China, 72. 



Wurtz (Dr.) on a new series of al- 

 cohols, 532. 



END OF THE TWELFTH VOLUME. 



PRINTED BY TAYLOR AND FRANCIS, 

 RED LION COURT, FLEET STREET. 



