i have problem to conceptualize this old galvanometer readings for voltage drop. i plot a diagram of circuit of interest for bether explanation of whats bothering me. so, in DC circuit with some resistor in series, electric current is constant and is of some known value. and if i want to use galvanometer to determine voltage drop on resistors, than it is enough (is it?) to plug it in parallel with resistor. than fraction (lesser the better) of main circuit current will loop in to galvanometer and deflect scale. once we have deflection, by knowing galvanometer resistance, we know interpret that as voltage drop. if we repeat measuring on R2, again litle fraction of main current enters galvanometer and again deflection is there. my question is why is deflection on galvanometer diferent on diferent resistors if the series current is constant and equal trough all resistors? or, why is fraction of main circuit current wich enters galvanometer, diferent on diferent resistor if the electric filed is constant trough wire?