The Midnight Express

The time is 1861...

      You appear in a clearing next to some railroad tracks...empty and forlorn in the midnight air.  It's hard to even imagine a train would be traveling along the track at this hour... but it is immediately clear that something is amiss.  At your feet is a lantern, illuminating a silver object in the grass.  

      As you pick it up to examine it more closely, you hear the rumble of the dark train as it rolls into view.  Knowing there is not much time, you hop onto the very last car and try to open the door before you are noticed.  It is locked, with a very strange keyhole.  A note next to the door gets your attention.

      Perhaps if you can figure out the meaning of this, you will be able to unlock the door in the "Objective" below.  Remember to use your hints if you are stuck.  

Objective

Unlock the door (Needs a word)

Hints