452 



INDEX. 



Walton (Miss E. M.) on liquefaction 

 and cold produced hj the mutual 

 reaction of solid substances, 290. 



Wheatstone's bridge, on the best 

 arrangement of the, for the mea- 

 surement of a particular resist- 

 ance, 283. 



theory of binocular perspective, 



on, 436. 



Wiedemann (Prof. Gr.) on molecular 

 magnetism, 223. 



Woodward (J. C.) on a wave-appa- 

 ratus to illustrate Fresnel's con- 

 ception of polarized light, 145. 



Wright (Dr. C. R. A.) on the num- 

 ber of electrostatic units in the 

 electromagnetic unit, 76, 224. 



Zircon, on a twin of, 26. 



END OF THE TWELFTH VOLUME. 



FUMMAM, 



Printed by Taylor and Francis. Eed Lion Court, Fleet Street. 



