50 Mr. Smithson on Mr. Penn's Theory concerning [July, 



in the caps of the jars, and the uncoated surfaces are var 

 nished, so that a spontaneous discharge seldom or ever takes 

 place without fracturing the jar. 



I am aware that the Pith Ball Electrometer is a very un- 

 certain standard ; and if my theory had depended on the 

 degree of intensity required to produce the effect with a jar 

 containing a given extent of coated surface, I should have used 

 the balance electrometer, invented by Mr. W. S. Harris, of 

 Plymouth, a description of which may be seen by referring 

 to page 77 of " Observations on the Effects of Lightning on 

 Floating Bodies, by W. S. Harris. London, 1823." 



I trust T. J. will continue the experiments, which, when 

 well matured, he has promised shall be submitted to your con- 

 sideration ; and, if he thinks I am in error, or has discovered 

 any facts which may militate against my opinions, I will either 

 most cheerfully answer them in the true spirit of philosophy, 

 which teaches us "to agree to differ," or I will prove to him that 

 I am not wedded to any system, and that no one would more 

 readily sacrifice a favourite theory, at the shrine of truth, than 

 myself. Should he, on the other hand, require any information 

 on a subject which has been for some years my favourite study, 

 I shall feel much pleasure in making the communication, if in 

 my power. I am, Sir, your obedient servant, 



Charles Woodward. 



Article XI. 



Some Observations on, Mr. Petal's Theory concerning the Forma- 

 tion of the Rirkdalc Cave. By James Smithson, Esq. FRS. 



(To the Editor of the Annals of Philosophy.) 



SIR, June 10, 1824. 



No observer of the earth can doubt that it has undergone 

 very considerable changes. Its strata are everywhere broken 

 and disordered ; and in many of them are enclosed the re- 

 mains of innumerable beings which once had life ; and these 

 beings appear to have been strangers to the climates in which 

 their remains now exist. 



In a book held by a large portion of mankind to have been 

 written from divine inspiration, an universal deluge is recorded. 

 It was natural for the believers in this deluge to refer to its 

 action, all, or many, of the phenomena in question; and the 

 more so as thev seemed to find in them a corroboration of the 

 event. 



Accordingly, this is what was done, as soon as any desire 

 to account for these appearances on the earth became felt. 



