Page:Scientific Memoirs, Vol. 2 (1841).djvu/491

Rh change places with each other; because, according to the laws of tension observed with respect to metals, this transposition would, it is true, alter the individual tensions, but not their sum.

The conclusion arrived at in II. 2. presents a convenient means for the determination of the conductibility of various bodies. If, for instance, we imagine two prismatic bodies, whose lengths are $$l$$ and $$l'$$, their sections respectively $$\omega$$ and $$\omega'$$, and whose powers of conduction are $$\chi$$ and $$\chi'$$, and both bodies possess the property of not altering the current of a galvanic circuit when they alternatively form a portion of it, and both leave the individual tensions of the circuit unchanged, then consequently