INDEX. 



309 



Smut of wheat, i. 281 



Snails, structure of, ii. 235-237 



Soda, chlorate of, singular property of, in crystallization, i. 75 



Soda, oxalate of, formation of, i. 117 



Soda, silicate of, i. 110 



Prof. Graham's dialysis of, i. 110 

 Soda, former and present mode of procuring, i. 128 



yellow coloured light produced by the combustion of, i. 132 

 abundance in the Algae, i. 414 

 Sodium, i. 3 



atomic weight of, compared with that of hydrogen, i. 100 

 spectrum analysis of the rarefied vapour of, i. 141 

 chloride of, spectrum of, i. 146 



reversion of the coloured lines of sodium burning in air, i. 150 

 Solar spectrum, i. 58 



myriads of ethereal waves constituting the seven colours of the, 



i. 58 



rayless spaces crossing the, at right angles, i. 59 

 length of the undulations of the ether producing the impression of 



the colours of the solar spectrum, i. 59 

 mode of bringing the invisible rays of the chemical spectrum before 



the human eye, i. 59 

 fluorescence and calorescence, i. 60-62 

 experiments producing the long spectrum, i. 63 

 spectra of volatilized metals, i. 64 

 absorption of invisible rays, i. 65 

 discoveries of Sir Isaac Newton of the solar spectrum and the laws 



of coloured rings, i. 129 

 Fraunhofer's lines, i. 129, 148 



]VDI. Bunsen and KirchhofFs experiments, i. 130, 148 

 Mr. Grlaisher's experiments, i. 130 

 absorption bands, i. 131 



Sir D. Brewster's discovery, i. 131 

 coincident dark and coloured lines, i. 148 

 reversion of the coloured lines, i. 149 

 Prof. J. P. Cook's discoveries, i. 149 

 M. Foucault's discoveries, i. 149 



M. KirchhofFs discovery of the law of exchanges, i. 150 

 metals shown by MM. Kirchhoff and Angstrom to exist in the sun, 



i. 151-153 



and those proved to have no existence in the sun, i. 154 

 Solferino, production of, i. 127 



