444 Dr Davy on Atmospheric Electricity. 



fore described, the needle, in a spiral which was then included 

 in the circle, was not sensibly magnetized. 



As the copper-conducting wires, during the period of experi- 

 menting, were undergoing oxidation, it was not impossible that 

 the feeble effects which occurred in fine weather, indicated by a 

 very slight precipitation of iodine, might be connected with the 

 chemical change the wires were experiencing. To put this to 

 the proof, gold wires were substituted for the copper throughout. 

 The results were still similar. Whence it may be inferred that 

 the results in question were not connected with the oxidation of 

 the copper wires, and that they depended solely on the foreign 

 influence they were the means of communicating. 



It was my wish to have instituted other experiments, in more 

 favourable situations, for witnessing the effects of atmospheric 

 electricity acting with greater energy, — but hitherto I have been 

 prevented. Other inquirers who have the means and leisure, I 

 trust will enter upon the subject and investigate it farther. In 

 the mean time, it may be asked, how do the results of electro- 

 chemical action described above, accord with those referred to 

 obtained by Mr Barry ? Making allowance for difference of 

 intensity, they appear sufficiently well to harmonize. Whilst 

 water was rapidly undergoing decomposition in his experiment, 

 he experienced shocks on touching the conducting thread con- 

 nected with the electrical kite. In none of my experiments did I 

 ever obtain any shock or spark from the insulated conductor, 

 therefore it is not surprising that the chemical effects I witness- 

 ed were so much feebler, and that only slight indications were 

 afforded of the decomposition of water. 



Mr Faraday, comparing Mr Barry's results with the effects 

 of common electricity and of voltaic electricity, justly points out 

 that they are not identical with either. The same remark will 

 apply not less forcibly to the results of the foregoing experiments.* 



* In the abstract of Mr Brande's Bakerian Lecture for 1819, though, not that 

 can find in the lecture itself, it is stated, that " the brilliant light occasioned by 



