304 PHENOMENA MANIFESTED IN TELEGRAPHIC LINES, ETC. 



ory may still be adopted as general expositioD of the pbenomeua, al- 

 though it may require to be supplemented with additional hypotheses. 

 It seems to me that this can be done by admitting, with Sir John Her- 

 schel, that between the sun and the planets there may be an interchange 

 of electrical currents. In such a case these currents will be at different 

 times more or less intense, according to the position and the distance 

 which the planets occupy in space with respect to the sun and to each 

 other ; and on this account the resulting phenomena will be subject to 

 a periodicity. If we admit that between the different bodies of our sys- 

 tem there is a continuous exchange of electrical action, that is, if we ad- 

 mit that there exists a cosmical electricity, the former may combine with 

 the natural electricity of the earth, and produce almost constant auro- 

 ras at the poles, whera the terrestrial magnetism is more energetic; then, 

 if from any cause whatever the cosmical electricity increases, the north- 

 ern lights may increase correspondingly, so as to become visible even in 

 places very distant from the poles. 



If the existence of cosmical electrical currents is admitted, we may 

 also imagine that in certain cases an electrical discharge takes place 

 toward the sun or from it ; in such a case we can conceive that certain 

 phenomena can occur only in such places as have a certain direction and 

 a certain position with respect to that discharge. Consequently such 

 l)henomeua will make themselves visible successively under the differ- 

 ent meridians, according as, by the diurnal motion of the earth, they 

 come to occupy successively the same position and the same direction 

 with respect to the discharge which we have imagined. It is true that 

 we have no direct proof of these cosmical electrical currents, but it is a 

 very old idea, put forth by Galileo, Kepler, and many other philosophers, 

 that the sun and the planets may be magnetic bodies, and why not 

 electrical as well as the earth? and if this is the case, (which seems very 

 natural,) it may also be admitted that through that ether which is gen- 

 erally admitted as filling the universe, there may be an interchange of 

 electric currents between planet and planet, and between the planets 

 and the sun. 



Sir John Herschel, in a note at the end of the fifth chapter of his 

 astronomy published in 1833, writes as follows : 



"Electricity traversing excessively rarefied air or vapors gives out 

 light, and, doubtless, also heat. May not a continual current of electric 

 matter be constantly circulating in the sun's immediate neighborhood, 

 or traversing the planetary spaces, and exciting, in the upper regions of 

 its atmosphere, those phenomena of which, on however diminutive a 

 scale, we have yet an unequivocal manifestation in our aurora borealis *? 

 The possible analogy of the solar light to that of the aurora has been 

 distinctly insisted on by my father, in his paper already cited. It would 

 be a highly curious subject of experimental inquiry, how far a mere re- 

 duplication of sheets of flame, at a distance one behind the other, (by 

 which their light might be brought to any required intensity,) would 



