202 Mr. J. J. Waterston on some Electrical 



mentioned before, although it can hardly have escaped the notice 

 of experimenters. 



(8 b, &c.) Are due to a similar quality of shell lac, and probably 

 other non-conducting surfaces. If the electric fire consists of 

 strongly excited molecules, we may remark that when in such 

 condition of excitement, and moving probably with inconceivable 

 velocity, they appear not to obey any ordinary law of projectile 

 force. They seem for the time to form part of the polarized 

 sether, and to be in the grasp of an agent of transcendant attri- 

 butes. As it is in the spark, so must it be in the lightning, 

 the amazing mechanical effects of which must be due to the 

 matter issuing from the surfaces of discharge. 



(9.) Such phenomena might be anticipated of a heterogeneous 

 body consisting of a perfect dielectric substance (if such a sub- 

 stance really exists, but clear amber is not) containing conducting 

 particles equally distributed throughout its mass, each one par- 

 ticle being separate and isolated from its neighbour. The appa- 

 rent induction at first seems evanescent; but in subsequent 

 experiments it will be remarked that, if exposure lasts for some 

 minutes, persistent inductive excitement appears on the surface 

 adjacent to the one excited. 



(10.) We may remark in this, that while brush discharge and 

 convective discharge of less intensity (1) takes place upon a non- 

 conducting surface, the spark discharge does not take place 

 without forcing it open : the coating is lifted up at both dis- 

 charging surfaces, therefore metallic particles issue from both. Is 

 such the case in lightning between the cloud and the ground ? 

 Does the flash consist of luminous water on one side, that Of the 

 cloud ? Towards the ground there may be many surfaces of 

 discharge, at each of which polarized molecules issue giving rise 

 to so many different foci of explosion. 



(21.) This effect is what would take place by separation of 

 polarized molecules from the metal that strokes the wax surface, 

 because the excitement is located on the surface stroked. Yet it is 

 difficult to see that this is likely, the wax being much softer than 

 the metal, especially when it is steel — as the side of a steel blade. 



(22.) The rate of discharge diminishes with the intensity : 

 combustion being chemical action, and chemical action being also 

 electric action, the electrically-excited molecules of the oxygen, 

 carbon, or hydrogen may fly to the excited body under the influ- 

 ence of its induction, which though weak may yet be stronger 

 than that of the combining element. Erom 29 d. it appears that 

 molecules do actually proceed from the flame to the near surface 

 of the wax screen, which, with the B. D. and intermediate air as 

 dielectric, becomes a charged magic pane arrangement, the B. D. 

 forming one side and the screen the other. 



