hmm..interesting!
I have a feeling it wasn't actual LV trackage..
One thing that popped into my head: perhaps it is referring to the PRR electric line that carried LV passenger trains from Newark to Penn Station..
PRR GG1's handled LV trains for many years..
Was that 13 miles? dont know..hold on, I will ask google..
Hunter Tower in Newark was where the LV handed off passenger trains to the PRR:
http://www.signalbox.org/overseas/usa/hunter.htm
Cant find the exact mileage from railroad timetables..but looking at modern maps,
13 miles is about right! I bet that is what the book is referring to..
another theory..
could be referring to electric "mules" at waterfront ports..
not railroad electrification in the traditional sense, with electric locomotives and catenary,
but that could also be what the book was referring to..
But IMO the book is almost certainly referring to the "LV route" between Penn Station and Newark..
in reality the PRR, and electric..
Scot