It is probably an air operated swaging or forging hammer similar to a
blacksmiths forging hammer. The tank showen is likely the air
reciever. These things used a large volume of air. The swagers I
worked on as an apprentice were used to squeeze down the end of
alluminum extrusions which were then pulled through a die to reduce
the size and give a better finish and hardness. The whole area around
these pictures looks like it was once inside a building probably a
heavy fabrication shop or such. One old shop near here ( closed and
torn down in the 60's) fabricated railway locomotives. The often used
just the rail car trucks to move very heavy peices from one section of
the factory to another. Just a guess. Hope this helps.
Herb