INDEX. 



647 



VIO 



Violet rays, discovery of blacken- 

 ing of silver salts in, 544 



Volatile bodies, discovery of, 551 



Volatility of substances in general, 

 discovery of, 551 



Volition in research, necessity of 

 powerful, 61 



subjection of to the great prin- 

 ciples of nature, 127-133 



Voltaic arc,' discovery of the, 561 

 of the effect of magnet- 

 ism on the, 561 



circuit, discovery of the spon- 

 taneous completion of the, 561 



combustion of leaf metals, dis- 

 covery of, 547, 560-561 



current, discoveries by means 

 of the, 546-547 



discovery of its effect on lit- 

 mus paper, 554, 568 



of its influence on a mag- 

 net, 180, 570 



of Ohm's formula of the 



quantity of the, 593 



of the chemical effect of 



the, 546-547 



origin of the, 592- 



593 ' 



decomposition of water, dis- 

 covery of the, 481, 535-536, 

 546-547, 554 



discharge, discoveries respect- 

 ing, 561 



electricity, discovery of, 492, 

 543 



accumulated, 481 



discovery of the earliest fact 



in, 535 

 that charcoal conducts,535 



pile, the, 481 



Voltameter, invention of the, 568 

 Volta's discoveries, 226, 481-483, 



543 



invention of the electrophorus, 

 480 



Von Baer's discoveries in embryo- 

 logy, 603 



inference that all animals are 

 formed upon one general plan, 

 603 



WHE 



Von Kleist's discovery of the Ley- 

 den jar experiment, 234, 480 



Von Marum's electric machine, 

 480 



WALLACE'S doctrine of de- 

 scent, 603-604 



Wallerius's discovery of derivative 

 forms of crystals, 601 



Wall's hypothesis respecting the 

 identity of electricity and light- 

 ning, 592 



Wargentin's discovery that the 

 aurora affects a magnet, 570 



Warltire's discovery of moisture 

 from exploded oxygen and hy- 

 drogen, 541 



Wartmann's discovery of rotation 

 of polarised heat by magnetism, 

 522, 543 



Water, discoveries respecting the 

 formation and composition of, 

 541, 544, 554 



temperature of boil- 

 ing, 529 



discovery of its formation by 

 synthesis, 557 



of the voltaic decomposition 



of, 481, 535-536, 546-547, 554 



Watson's discoveries respecting 

 electricity, 633, 567 



Watt's discovery of the pressures 

 of steam at different tempera- 

 tures, 479 



Wave of light, breadth of a, 32 



Wealth, influence of upon the 

 power of research, 273 



Wedgwood's discovery respecting 

 photography, 590-591 



Weiss's systems of crystalline 

 forms, 601 



Wells 's discoveries respecting 

 electricity, 535, 567, 568 



Wenzel's discovery of reciprocal 

 and definite chemical propor- 

 tions, 540-541 



Wheatstone's discovery of the ve- 

 locity of a voltaic current, 511 



inventions, 475, 486 



