208 G. Th. Fechner's Justification of the 



or sodium is in the oil of naphtha, then a small quantity of 

 humidity has been introduced into the liquid, which had re- 

 mained adhering to the surfaces of the two metals, and which 

 exercises on them a chemical action which it is easy to recog- 

 nise. Immersed in azote and in hydrogen the two metals still 

 gave rise to a development of electricity proceeding from the 

 action exerted upon them either by the gases, or by the 

 aqueous vapour, from which it is impossible entirely to free 

 them (?) ; and in proof of this chemical action, we see their 

 surfaces lose their metallic brightness and become tarnished 

 very much as would have taken place in the air." 



The result which I would draw from a repetition of this 

 experiment is this ; that in the form adopted by De la Rive, 

 it is altogether unfit to give a proof of the one or the other 

 view, because potassium brought into connexion with the earth 

 by means of dried wood, does not allow us to perceive either 

 out of or in petroleum, [steinol] any development of electricity, 

 which, according to both views, is explicable from the pro- 

 perty of the condenser ; but brought into connexion with it, 

 by means of moist wood, it immediately produces, both in and 

 out of the petroleum, powerful action, which the supporter of 

 the chemical view can explain from the chemical action pro- 

 duced through the moisture, the supporter of the voltaic 

 theory, from the increased conducting power of the wood ; of 

 the influence of which in this case sufficient evidence is con- 

 tained in the following details. The experiment, however, 

 may be, in fact, so varied, that it becomes decisive, and in 

 this form it speaks, as will be seen, against the chemica. 

 theory. The following is the detail of the experiments. 



A potassium ball was furnished at two opposite points with 

 fresh surfaces of section : into one surface was inserted the 

 end of a platinum wire, into the other the end of an air-dried 

 bar of wood, so that the ball was situated between both ; now 

 the highly sensible condenser (at times brass, at times copper) 

 which was connected with the electroscope with a dry pile 

 described by me in these Annals, was brought into contact 

 with the platinum, while the wood was held in the hand. I 

 could perceive by the well-known manipulation with the con- 

 denser either no, or very inconsiderable, traces of electricity. 

 I then substituted for the wood a cut chip of a quill, and ob- 

 tained the same result. If on the contrary. I held the potas- 

 sium ball in the hand, and brought the condenser into con- 

 tact with the platinum, I obtained a divergence of the gold- 

 leaf, of remarkable strength*, without comparison much more 



* This was even the case when the potassium ball was not cleansed 

 from the adherent petroleum ; and I cannot in the least from my experi- 



