“Ten O’Clock Low” CSX 0171 (OBSS), with RF&P GP40-2 141 plus three, is westbound at Rossville interlocking on CSX's (former B&O) Philadelphia Subdivision. The conductor appears to be alerting the engineer, perhaps somewhat belatedly, to my presence. My guess is something to the effect of “Heads up, Charlie. Ten o’clock low. It’s another FRN with a Nikon!”