With the help of Mr. Peabody's Wayback machine we will go to 1852 and find out about the Susquehanna ice bridge.
When the winter ice floes came down the river and jammed up solid so the ferry couldn't run, the train traffic from Baltimore to
Philly stopped. No problem, just build a bridge on the ice. What?
I read some of the river is 60 feet(18.3m) deep in that area but sandbars not very deep catch the ice causing it to back up and
freeze solid, the subsequent floes are forced down and under the jam making it thicker.
I don't think I'd ever be that determined to get to Philly.
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