The Native Americans from this area would (as a boy wanting to become a man) get up in the morning on the coldest day,remove all clothing, walk, not run, down to the river....chop a hole in the ice...dive to the bottom and feel around for an object. This object , whatever it may be, was kept private and placed in the bag as part of his "mojo" or "medicine". If memory serves correct they did this 3 or 5 times in a row. Must always walk to and from the river showing no signs of anguish. Similar thing there?