Columbia Center --
The cranes were on top of towers 6 stories tall.
The building would be built around the towers until it came up to the crane,
at which point the cranes would have to be "jumped".
The process of raising the cranes required that
winches be placed at each corner of the base of the crane,
which would then pull the crane out of the hole it had built itself into.
Engineers with survey rigs stood to the sides,
while steelworkers with 4x4's would apply tension to the pulleys and keep the cable winding properly.
During this process, the only thing holding the crane was the cable at each corner:
A very delicate balancing act.
The crane is a bit soft in this picture as it has started it's upward progress.
Photograph by K. L. Slusher