338 Refleclions on the Inadequacy of ihc principal Hypotheses 



as, if it did, it could only, he observes, penetrate in one direc- 

 tion. To t'onclude: bct-au'^e the passage is effected in two dif- 

 ferent directions, that nothing ])assed, aj)])ears to me an in- 

 ference of a very questionable natnre. Sir H. Davy attributes 

 the phainonionon to attractions acting in opposite directions. 

 But were this so, a battery disciiarged through a quantity of 

 light powder should collect it round the wires when the circuit 

 was interrupted ; uhereas it is dispersed in all directions. On 

 the whole it is not likely that the opinion of Sir H. Davy will 

 become general ; it therefore need not be more minutely dis- 

 cussed. 



That the electric matfer is an clastic fluid is a position that 

 does not appear to be sufficiently supported. The experiments 

 which are supposed to countenance this principle are two, along 

 with some others which do not deserve nmch consideration. 

 First, l)odies which beside their natural quantity contain an ex- 

 cess of electricity, in a free state, are found to repei each other ; 

 the repulsion being attributed to the particles of the fluid 

 acting on each other. Secondly, the electric m.atter when 

 issuing from a pointed body in open air, appears like a diverging 

 cone of rays, which Dr. Franklin thinks must be caused by self 

 repulsion. 



The evidence in favour of both these opinions is very insuffi- 

 cient. In the former case, there is no certainty that there is an 

 excess, and in the latter, proof is wanted that electric matter is 

 then issuing from the point. With regard to the repidsion of 

 bodies in sinrilar states, it certainly takes place in many experi- 

 ments. I have, however, oljserved an instance in which no re- 

 pulsion, but an attraction takes place. 



Let a pith ball be suspended from a glass rod, and let an ex- 

 cited tube be brought under it, but so as not to touch. If the 

 tube be now moved a little to one side from under the ball, the 

 latter follows the tube for a short distance, but as the suspended 

 ball in moving describes a curve, its gravity at length overcomes 

 the attraction of the tube, it separates a Httle, and having now 

 received the state of the tube, it is immediately repelled to a 

 great distance. When the tube is again approached, the hall is 

 still repelled : but when the tube is forced still nearer, the ball is 

 attracted, and continues to be so until the tube being removed 

 as at first, it separates by its weight and is immediately repelled 

 as before. The same effects may be produced by any other 

 electric. The results iray at first be doubtful, but by repetition 

 they will clearly show that in this instance the electric matter 

 causes either attraction or repulsion as the distance is small or 

 great. 



As to the diverging rays proceeding from a point, their evi- 

 dence 



