INDEX. 



643 



SEN 



Senses, range of our,extension of by 

 means of instruments, 471-472 



Series, discovery by assuming the 

 existence of homologous, 523 



of causes, 406, 414, 430-431 

 Shape of the earth, discovery of 



the true, 608 



Siemens's discovery of electric 

 charge of underground tele- 

 graph wires, 568-569 



Silver in the Pacific Ocean, dis- 

 covery of, 503-504, 558-559 



Similarities and differences, de- 

 tection of, 328-329 



Similarity as an aid to discovery, 

 327 



as a bond of memory, 112-113 

 Simultaneous discovery, instance 



of, 578 



invention of the Leyden jar, 480 

 Sleep, conditions of, 39, 260-261 

 Smee's ' relational machine,' 54 



battery, invention of, 485 



< differential machine,' 330- 

 331 



Snow Harris's invention of bifilar 



suspension of magnets, 485 

 Societies, learned, influence of on 



research, 285 



Sodium, &c., discovery of, 522 

 Solar heat, discovery of the annual 



amount arriving at the earth, 



610 

 its great amount, 32 



outburst, discovery of a, 578 



spectrum, discovery of dark 

 bands in the, 527 



of the true explanation 



of dark lines of the, 578-579 



ultra-violet rays of 

 the, 544 



respecting the Iieat of 

 the, 510-511 



spots, discovery of, 566 



discoveries respecting the, 



566, 577, 587 



system, discovery of the motion 

 of the entire, 587 



Solidification of carbonic anhy- 

 dride, discovery of the, 531 



STA 



Solvent powers of liquefied gases, 

 discovery of, 543-544 



Sorby and others' discoveries of 

 the effect of pressure on melt- 

 ing-points, etc., 559-560 



Sound, discovery respecting the 

 transmission of, 527 



Sounds, discovery of electrolytic, 

 238, 518-519 



respecting the inaudibility 



of certain, 527 



transmission of, 

 527 



Sound wave, amplitude of a, 32 



discovery respecting the ve- 

 locity of, 474-475, 491 



Sources of false belief and error, 

 103, 111-137 



of scientific ideas, 51 



Space, discovery respecting the 

 temperature of, 587-591 



immensity of, 31 

 Spallanzani's physiological dis- 

 coveries, 541-542 



Specific gravity of a mountain, 



discovery of the, 586-587 

 of the earth, discovery of 



the, 586-587 

 of the planets, discovery of 



the, 608 

 Spectra, discoveries respecting the 



bands of various, 527-528, 574 



of rarefied gases, 536 

 Spectrum analysis, discoveries in, 



545-546, 590 



discovery of, 178-179 



prelumined, 178-179 



suggestion of by Herschel, 



590 



discovery of the solar, 478 

 of the bands of the solar, 



527 

 of the dark heat rays of the 



solar. 510-511, 547-548 

 of the ultra-violet rays of 



the solar, 544, 573 



of iron, great complexity of the, 

 33 



Star maps and catalogues, dis- 

 covery by means of, 577 



T T 2 



