V^OL. XLVm.] FHILOSOPHICAL TRANSACTIONS, 37-5 



experiment. In this letter it is examined, whether the effects of this experiment 

 proceetl from the glass phial, or trom the non-electrics contained in it ; and 

 experiments are pi-oduced to prove, that the power of giving a shock in an elec- 

 trized phial of water, proceeds from the water in the phial, and not from the 

 phial itself, as Mr. Franklin imagines. In this letter likewise is an examination 

 of Mr. Franklin's opinion, that in the charged phial, as much fire as is received 

 by one of its surfaces is lost by the other.,n(f{ ai) 



The 5th letter to Mr. Franklin is in respect to the power of pointed non- 

 electric bodies drawing off and throwing off electrical fire, at a much greater 

 distance than obtuse bodies do of the same kind. Our author thinks, that Mr. 

 Franklin has attributed more power to pointed bodies, than on experiment he 

 finds to be true. 



The 6th letter to Mr. Franklin is on the analogy of thunder with electricity. . 

 This is a fact at present so well established, as to admit of no doubt. But our 

 author cannot agree with Mr. Franklin in his opinion, " that thunder is at pre- 

 sent in the power of men, and that we are able to dissipate it at our pleasure : 

 that an iron rot! (such a one as Mr. Franklin has directed, and such a one as 

 has been made use of) is sufficient to discharge of all its fire a stormy cloud 

 against which it is directed," For his part he confesses, that he cannot believe, 

 it ; first, because he sees too great a disproportion between the effect and the; 

 cause : secondly, because the principle, which is given us to support this opinion,, 

 is not sufficiently established. He can hardly think, that the fulminating matter 

 contained in a cloud, capable of covering a great city, can be drawn off in a few 

 minutes by a pointed bar, as thick as your finger. If even a number of these 

 placed on the tops of eminencies were only necessary to prevent the effects of 

 thunder, would not the vanes and crosses at the tops of our steeples have been, 

 sufficient to procure us this advantage ? These buildings however, in all timesy 

 have not been exempted from the mischiefs of thunder. He despairs of our weak 

 efforts ever being able to disarm the heavens. 



In this letter are also considered the validity of Mr. Franklin's hypothesis o£ 

 electric and non-electric clouds ; the former arising from the sea, the latter from.' 

 the land ; their operation approaching near each other ; the difference, according 

 to Mr. Franklin, between electrical and common fire ; and several other parts of 

 Mr. Franklin's doctrine. 



The 8th letter is addressed to M. Jallabert of Geneva ; and, among other 

 curious particulars, inserts part of a letter, which our author had received from 

 Mr. Jallabert, giving an account of an experiment, which Mr. Jallabert had 

 some time since made at the water-works at Gtcncva. An account of this ex- 

 periment was communicated by Mr. W. to the Society ; and it has a near rela- 

 tion to the experiment which was made here in electrizing the river Thames (J 



