This picture was taken from the tunnel-end of the trestle (south end) looking northward.  Note the tank car at the far end of the trestle and the marooned tank car 50ft above it.  These tank cars are plumbed together with piping, forming a water supply for fighting fires on the trestle and along the rail lines.  Remember, the turn-of-the-20th-century trains ran on coal and were steam engine powered.... lots of opportunity for burning embers to light the place on fire.  I'll bet railroad men hate it when that happens:)