si 



service. If a tcx> strong potential is turned upon a 

 thin wire, the impact on the molecules or co-s, is more 

 than they can b :hat tin- wire is unable to carry 



the- potential ; the atoms and molccul* pushed out 



of the an-le t<> which they arc capable of sum^in^, the 

 molecules conic into counter friction with each other, pro- 

 ducing heat, which, if allowed to go on, raises the \\ ire to a 



f incandescence, and eventually burns it up. 

 Of course, current electricity or molecular vibrations 

 the easiest path, and naturallythosc on the outside. >f the wire, 

 in contact only with the atmosphere and the ether, vibrate 

 the most easily. Thus it is made clear that when the el< 



arc covered, as in cables or under-ground wires, the 

 :nij interferes with the free molecular stress or vibra- 

 tion, and slows the telegraph speed, as is so well-known. 



An illustration has sometimes been .iMven of current 

 electricity lies of billiard balls connected together ; 



hit one, and the last one replies. Such is not a true repre- 

 sentation of the case. It rather resembles a series of cog 

 wheels ; vibrate one, and the last molecular cog at the other 

 end of the metallic connexion turns, vibrating in reply. The 

 billiard ball illustration would more aptly apply to the 

 telephonic instruments, which occasionally have been 

 arranged to work on the same wire and at the same time 



he cog-wheeled vibratory current electricity. 

 Professor Clausius has stated his belief that there arc 

 only two material forces at work heat and electricity. I 

 believe there is only one (save the physical material pro- 

 perties of matter), viz. : heat ; and that electricity and light 

 proceed from it. 



The relative positions of molecules and atoms in solids 

 beiiuy fixed, and contiguous to each other, when the expen- 

 diture of force comes, effects are communicated that arc 

 well-known. Molecules in the liquid state, more readily 

 glide past one another, and they assume the form of any 



