The Chicago Water Tower: Survivor of the Great Chicago Fire

In 1871 there was a horrible, HORRIBLE fire in Chicago that destroyed nearly all of its downtown. It's called the "Great Chicago Fire", but nobody thought it was that "great".
Only a handful of buildings survived the fire: one is Old St Pat's on Adams & Des Plaines.
The other was a building that was used to put out fires: the Chicago Water Tower on Michigan and Chicago.