ISogal institution of ffireat tSritain. 



I860. 



WEEKLY EVENING MEETING, 



Friday, May 18, 1860. 



Charles Wheatstone, Esq. F.R.S. Vice-President, in the Chair. 



Fbofessoh William Thomson, F.R.S. 

 On Atmospheric Electricity, 



Stephen Gbay, a pensioner of the Charter-house, after many years of 

 enthusiastic and persevering devotion to electric science, closed his 

 philosophical labours, about 130 years ago, with the following remark- 

 able conjecture ; " That there may be found a way to collect a greater 

 quantity of the electrical fire, and consequently to increase the force 

 of that power, which by several of these experiments, si licet magna 

 componere parvis, seems to be of the same nature with that of thunder 

 and lightning." 



The inventions of the electrical machine and the Leyden phial 

 immediately fulfilled these expectations as to collecting greater 

 quantities of electric fire ; and the surprise and delight which they 

 elicited by their mimic lightnings and thunders, and above all by the 

 terrible electric shock, had scarcely subsided when Franklin sent his 

 kite messenger to the clouds, and demonstrated that the imagination 

 had been a true guide to this great scientific discovery— the identity of 

 the natural agent in the thunderstorm with the mysterious influence 

 produced by the simple operation of rubbing a piece of amber, which 

 two thousand years before had attracted the attention of those philoso- 

 phers among the ancients who did not despise the small things of 

 nature. 



The investigation of atmospheric electricity immediately became a 

 very popular branch of natural science ; and the discovery of remark- 

 able and most interesting phenomena quickly rewarded its cultivators. 

 The foundation of all we now know was completed by Beccaria, in his 

 observations on "the mild electricity of serene weather," nearly a 

 hundred years ago. It was not until comparatively recent years that 

 definite quantitative comparisons from time to time of the electric 

 quality manifested by the atmosphere in one locality were first 



Vol. III. (No. 33.) u 



