ON ELECTRICITY IN EQUILIBRIUM. 667 



glass may be discharged by a moderate heat, and liquid resins are capable of 

 transmitting shocks, although they are by no means good conductors: it is 

 remarkable also that ajar may be discharged by miuute agitation, when it is 

 caused to ring by the friction of the finger, Ic has oeen observed that, in a 

 great variety of cases, those substances, which are the best conductors of heat, 

 attbrd also the readiest passage to electricity; thus, copper conducts heat 

 more rapidly, and electricity more readily, than iron, aijd platina less than 

 almost any other metal; glass also presents a considerable resistance to the 

 transmission of both these influences. The analogy is, however, in many re- 

 spects imperfect, and it affords us but little light, with regard either to the 

 natore of heat, or to that of the electric fluid. 



