Resistance.--Exp. 118, To study the general effect of
"resistance" upon a current.--External Resistance; Internal
Resistance; Unit of Resistance; The Ohm.--Resistance Coils;
Resistance Boxes.--Simple Resistance Coil.--Exp. 119, To
test the power of various substances to conduct galvanic
electricity.--Conductors and Nonconductors.--Exp. 120, To
find the effect of sulphuric acid upon the conductivity
of water.--Internal Resistance.--Exp. 121, To find what
effect the length of a wire has upon its electrical
resistance.--Discussion.--Exp. 122, To find what effect the
size (area of cross-section) of a wire has upon its electrical
resistance.--Discussion.--Exp. 123, To compare the resistance of
a divided circuit with the resistance of one of its branches.
Discussion.--Exp. 124, To study the effect of decreasing the
resistance in one branch of a divided circuit.--Current in
Divided Circuits.