NATURAL PHILOSOPHY. 



electricity of varying intensity through 768 miles of gutta percha wire, indi- 

 cating a velocity of propagation of about 1,000 miles in a second, which 

 velocity is sensibly uniform for all intensities from 31 cells to 500; which 

 results, Dr. Faraday remarks, "afford a fine argument hi favor of the opinion 

 of those who suppose the electric current to be analogous to the vibrations of 

 air under the action of sonorous bodies." The experiments of Professor Grove 

 on the electro-chemical polarity of gases, where he obtains rings alternately 

 bright and oxidated, showing effects of oxidation and reduction by the same 

 current on the same plate, he considers as "analogous to the phenomena of 

 interference hi light ; though doubtless, if this be a right view, the very dif- 

 ferent modes of action of light and electricity would present very numerous 

 phenomenal distinctions." The idea has lately been presented to my mind, 

 that the oscillations of the electrical aether in combination with the particles 

 of the medium conveying a current, produce undulations, not only in the 

 asthers of light and heat, but also hi another aether, which Dr. Draper calls the 

 tithonic sether, but which, if experiment proves to be the case, should be more 

 correctly termed the electrical sether. 



Dr. Draper, hi the year 1847, undertook a series of experiments upon the 

 rays of light emitted by incandescent bodies, from which he concluded that 

 when a platinum wire is heated by the voltaic pile or otherwise, it emits rays 

 of light, which increase in refrangibility proportionally to the increase of heat, 

 which he explains thus : "As the luminous effects are undoubtedly owing to 

 a vibratory movement executed by the molecules of the platinum, it seems 

 from the foregoing considerations to follow, that the frequency of those vibra- 

 tions increases with the temperature." Sir David Brewster has observed, 

 that hi the spectra produced by the electric light, the chemical rays are more 

 numerous than hi those produced by the lime light. The problem then to be 

 solved is whether the chemical rays be produced directly by the oscillations 

 of the electrical asther hi the platinum wire, or indirectly by the heat pro- 

 duced. 



This question might be resolved by observing the effect produced by voltaic 

 piles of different intensities, the heat remaining constant; and if so, it would 

 afford a strong argument in favor, not only of an oscillatory movement hi the 

 electrical sether in combination with the particles of bodies, but also of the 



existence of such an asther through space. 







ON THE OEIGIN OF THE AUEOEA BOREALIS. 



An important paper on the Aurora Borealis has recently been published 

 by the Smithsonian Institution, entitled, "The Eecent Secular Period of the 

 Aurora Borealis," by Professor Olmstead, of Yale College. The folio whig 

 extract from this paper will sufficiently explain its nature : 



" It has appeared to me incumbent on some one devoted to the studies of 

 nature, who has witnessed this exhibition of the Aurora Borealis, probably 

 among the most remarkable that have ever occurred since the creation of the 

 world, to write its history, to give an accurate history of its varieties, to pre- 

 sent at one view a classification of the principal facts, in order, if possible, to 

 ascertain the laws of the phenomenon ; and finally to determine the origin, 



