He was about half way across the river when the tree trunk moved suddenly, John fell from it onto the ice.

VOA: special.2010.06.26

The Yukon River turned to ice.Winter in this area was extremely cold.

VOA: special.2009.02.11

The ice over the river had melted when he reached it.

VOA: special.2010.06.26

Franklin Delano Roosevelt's uncle John was one of the founders of the Hudson River Ice Yacht Club in 1885, and his 48-foot Icicle is still on display in the Hudson River Maritime Museum in Kingston, N.

FORBES: Shiver Me Timbers

Heavy machinery was brought in to break up and remove ice from the river, so that boats and divers could get in, Sideras explained.

CNN: March 16, 2013 -- Updated 0041 GMT (0841 HKT)

The successful delivery of the serum was no foregone conclusion--temperatures of 50 or more below zero, blizzards, cracking river ice and winds that would suddenly hit a sled at 60 mph to 70 mph were everyday hazards.

FORBES: Going To The Dogs