638 



INDEX. 



PHE 



Phenomena, discovery of residu- 

 ary, 559 



fortuitous, 445 



frequency of coincident, 445 



modes of connection of, 427-429 



omnipresence of natural, 23 



relations of to each other, 429 



instances of discovery of re- 

 sidual, 433 



discovery by means of unex- 

 plained, 497 



Phenomenon, essential elements 

 of a natural, 447 



Philosopher, character of the sci- 

 entific, 363 



Phlogiston, theory of, 512-513, 595 



Phosphide of calcium, discovery 

 of, 518, 557 



Phosphorus bleached by chlorine, 

 discovery of, 1 92 



discovery and re-discovery of, 

 552 



Photography and photo-chemistry, 

 origin of, 544, 551, 590-591 



Physiological discoveries of Spal- 

 lanzani and Bonnet, 541-542 



psychology, researches in, 56- 

 59 



Physiology, discoveries in, how 

 made, 579 



Pictet's discovery of the liquefac- 

 tion of oxygen and hydrogen, 

 560 



Planet, discovery of the probable 

 existence of a missing, 488, 587 



discovery of the velocity pro- 

 duced by the explosion of a, 610 



Planets, Bode's discovery respect- 

 ing the distances of the, 610 



discovery of the specific gravi- 

 ties of the, 608 ' , 



Juno and Vesta, discovery of, 

 509-510 



Planning an experiment, 308-311 

 Plants, Goethe's suggestion re- 

 specting, 579-580 



discovery of the constituents 

 of, 539-540 



Pleasure of false beliefs, 95 



of scientific discovery, 10, 11 



PRE 



Pliicker's discoveries of the effects 



of magnetism on crystals, 562 

 Poisson's general expressions for 



the attractions and repulsions of 



magnetised bodies, 606 

 Polarisation of heat rays, discovery 



of, 485, 486 



of light, discovery of, 224-225, 

 489-490 



Polarised heat, discovery of mag- 

 netic rotation of, 543 



light, discoveries made by the 

 aid of, 551 



respecting, 478, 488, 489- 



490, 510, 522, 528-529, 551, 566, 



574, 590 

 discovery of the magnetic 



rotation of, 561-562 

 Porta's discovery of the principle 



of the camera-obscura, 527 

 Potassium, discovery of, 11, 230, 



483 

 Potts, numerous experiments made 



by, 385 

 Pouillet's discoveries, 555, 610 



invention of the astatic needle, 

 485 



Power of comparison, necessary 

 to discovery, 329 



of discovery, limits of man's, 

 169 



scientific imaginative, 365 

 Powers, finite character of all our, 



102-104 



Precession of the equinoxes, dis- 

 covery of, 565 

 of effects of, 577, 608 



of the cause of, 608 



Predicted discoveries, examples 

 of, 204, 227, 229-232, 524 



Prediction, basis of, 344 



by means of inference, 401 



of discoveries often incorrect, 

 233 



new chemical elements, 204, 



524 



successful, not a complete test 

 of truth, 146-147 



Prejudice, influence of, in research, 

 115, 246 



