Every outlet I have ever seen in older homes (1910-1930) has only two wirea in the box, they can't all be 'end of run'. Was this common practice back then? It doesn't seem like an efficient use of wiring. So what's going on within the walls? Are there main wires to which all these single lines connect? I am interested in upgrading my outlets and rewiring the whole system is not a option, I would instal a GFCI as the first outlet from the panel to serve as the next best thing to a true ground on each circuit, the problem is as I said each outlet seems to be alone on its circuit.
Any help is really appreciated.