636 



INDEX. 



NAT 



Nature of a discovery, conditions 

 which determine the, 456 



of scientific research, erroneous 

 notions respecting the, 3 



Nebulas, discovery respecting, how 



effected, 560 

 Needle, suspension of by means of 



magnetism, 537 

 Neglected parts of science, 468- 



469 



substances, discovery by ex- 

 amining, 501-502 



truths and hypotheses, dis- 

 covery by examining, 487 



Neptune, discovery of the planet, 



201-202, 227, 515, 609 

 Nerve-cells, number of in a human 



brain, 36 



current, rapidity of the, 56 

 Netherfield, discovery of gypsum 



at, 518 

 Newton and Kepler contrasted, 



249-251 

 Newton's discoveries, 173, 177, 



224, 388, 509, 517-518, 532, 546, 



547, 573, 585-586, 589, 597, 608 



discovery of the law of gravity, 

 173, 177, 224, 388, 509, 573, 585- 

 586 



failure of memory, 72 



great modesty and shyness, 

 244, 246-248 



power of attention, 61, 247 



(and others') inference of the 

 existence of chemical affinity, 

 597 



' Principia,' 219 



(of America) discovery respect- 

 ing meteors, 565 



Nicholson and Carlisle's discove- 

 ries, 546-547, 481, 535-536 



Nicholson's invention of a rota- 

 ting electric condenser, 481 



Nitrate of silver, blackening in 

 violet rays, discovery of, 544 



Nitric acid, discovery of, 551 



Nitrous oxide, discovery of some 

 of the effects of breathing, 

 542 



Nobili's discoveries, 485, 558 



OHM 



Nollet's discovery of the effect of 

 electricity on the flow of liquids, 

 567 



Nomenclature, necessity of proper, 

 76 



Norman's discovery of magnetic 

 inclination, 537, 570 



Notes of an experiment, taking, 

 317, 370-371 



November meteors, discovery re- 

 specting the orbit of the, 543 



' Nutation of the Earth's axis,' 

 discovery of, 238 



OBJECT of original research, 1 

 Objects, detection of minute, 

 323 



of search, useless ones, 20 

 Observation, acute powers of, as a 



means of success in research 

 124 



discovery by means of new 

 modes of, 573 



favourable conditions of, 322 



importance of qualitative, 316 

 - nature of, 60, 315-316, 318, 



319 



Observations in concrete subjects, 

 323 



cosmopolitan, 323-324 



imperfections of our, 321-322 



discovery by means of new, 

 563 



Observe, how to, 316-317 



Observing, limits of power of ap- 

 paratus for, 212 



powejs, limits of our, 211, 320 



Obscurity of coming discoveries, 

 25, 178 



Occult causes, assumption of as a 

 source of error, 124-133 



detection of, 125-126 



rule regarding, 418 



Occupations, scientific, influence 

 of, on research, 271 



Oersted's discoveries, 224, 226, 

 536, 547, 559 



Ohm's formula of the quantity of 

 the voltaic current, 593 



