Researches in the Theory and Calculus of Operations. 265 



with great rapidity of alternation, a single oscillation or 

 half- wave (semiatom) of force wo aid be evolved at each 

 end A and F of the system, the positive phase at one and 

 the negative at the other extremity; constituting the split 

 force of a single atom, separated by the intervening atoms 

 now reverting to equilibrium under the changed status: 

 the liberated semiatomic force at F is equilibrated by the 

 semiatomic force of E, etc., and so of the extremity A. As 

 there is no exact limit of intensity between the applied forces 

 requisite respectively to generate calorific or electric force, 

 it is readily seen why these two forces are always found 

 together, though in varied proportions, under like operations 

 whether mechanical or chemical. 



A comparison of the preceding examples of the rod and 

 row of balls offers a glimpse at the conditions which occa- 

 sion the difference between conductors and non-conductors 

 of electricity. Conductors are generally simple substances, 

 while electrics are usually compounds, or else formed of 

 conductors by compression. The simple element may be 

 counted as one atom for its whole length, or one dynamical 

 wave with a node at each extremity and venter at the cen- 

 tre ; while glass (silicate of sodium), resin, etc. are compounds 

 by virtue of chemical affinity, and therefore consist of sepa- 

 rate atoms or dynamical waves, as in glass one phase of the 

 wave consists of silicic acid, the other phase of sodium. 

 Crystalline and compressed forms will be explained in a 

 similar way. 



12. In the complete electrical machine, the most perfect 

 form is perhaps that of Nairne, an attempted theoretical 

 outline of which is given in the margin, both electricities 

 are collected from one operation. It may be composed of a 

 plate or of a solid or hollow cylinder of glass C C (fig. 14), 

 and two conductors P and all three insulated, and the 

 cushion* or rubber A attached to K. 



Prior to the operation, each molecule of the glass, of 



Trans. vn.~\ 34 



