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or mode of action of electrical force, but they are by no means 

 objectionable when denoting different amounts of the same force in 

 this or that direction. 



In considering the nature of electrical accumulation on coated 

 electrics and the law of explosive discharge, we have to deal with a 

 simple question of physical force taken in the abstract, and not with 

 a theoretical electric fluid or fluids of high elasticity, subject to ex- 

 pansion or contraction, changes in thickness of stratum, tension, 

 density, and the like. The terms "tension" and "intensity," so 

 commonly applied to designate degrees of electrical force, are con- 

 venient and not inappropriate terms when legitimately applied and 

 limited by definition. The term intensity is well adapted to express 

 the attractive force of the charge in the direction of the electrometer, 

 and which, in continually increasing according to a known law, ter- 

 minates in explosion. The intensity or attractive force varies with the 

 square of the charge. The term " tension " is more especially appli- 

 cable to the constrained state of the dialectric particles sustaining the 

 induction necessary to the charge, and is equivalent to the reactive 

 force of the particles in an interrupted circuit of discharge to break 

 down or reverse the polarized state of the dialectric medium impeding 

 discharge, as between the exploding balls of the Lane'* discharger : 

 this is as the quantity of charge directly. In employh these terms, 

 the author has not the least view to any specific changes in the quality 

 or condition of the accumulated electricity, as relating to density, 

 elasticity, and such like. "Whether the tension and intensity of a 

 charge, as evidenced by the electrometer, be great or little, he con- 

 ceives that the nature of the force and its mode of operation remains 

 the same. Viewing the process of electrical accumulation and dis- 

 charge in the Ley den jar as the result of certain powers or forces 

 operating either immediately through the glass or through an external 

 circuit, or both, we may readily imagine that at the critical point at 

 which the forces in the two directions become balanced, and at which 

 point the equilibrium of charge is, at it were, overset on the side of 

 the exterior circuit, then it is that residual charge ensues, either by a 

 momentary revulsion of force between the coatings in the direction of 

 the intervening glass, frequently causing fracture, or otherwise by a 

 retention of some of the charge in that direction at the instant of 

 explosion. Some instructive and important experiments by Mr. T. 

 Howldy are here quoted in support of this conclusion, from the 



