I have found a box that as three duplex electric cables connecting. The neutral (white) from wire 1 and wire 3 are connected. The hot (black) from wire 1 is connected to wire 2, and the hot from wire 3 is also connected to wire 2 - this I don't understand - two hots feeding one cable. What would be the purpose? Was there a reason why this would have been set up this way. All the wiring only connects to lights and outlets, as far as we know, and is circa 1960s, but professionally done.