General Electric boxcabs # 607 and 601 of the SQM, built in 1927 in Schenectady/NY, are pulling the empty uphill train from Tocopilla to Barriles on a grade of 4.0 %, after the crossing with the loaded downhill with E 652 and E 653 in Carmelita station. Carmelita, on km 12.23 and 420 meter a.s.l., has no passing loop, but only a dead end track with one switch, so the uphill train went in backwards for the crossing.