Douglas made sure he had conquered the old terror of water by deliberately testing himself in deep, open lakes and swimming long distances until he could face the water without any panic at all.

Direct answer

In the chapter ā€œDeep Water,ā€ Douglas did three key things to be certain he had defeated his old fear of water:

  1. He went to Lake Wentworth in New Hampshire, dived in near Triggs Island, and swam about two miles across the lake to Stamp Act Island.
  1. When the old terror suddenly returned in the middle of the lake, he faced it, refused to give in, and continued swimming using the strokes he had learned (crawl, breast stroke, side stroke, back stroke) instead of panicking.
  1. Still wanting complete assurance, he later went to Warm Lake (near Meade Glacier), dived in, and swam across to the other shore and back; after doing this without losing control, he knew the fear was truly gone.

So, he ā€œmade sureā€ by repeatedly challenging himself in real, potentially frightening situationsā€”first in Lake Wentworth and then in Warm Lakeā€”until he could stay calm and confident in deep water every time.

Mini view: what this shows about fear

  • Conquering fear required practice , not just lessons in the pool.
  • He consciously walked back into the very situation that once terrified him (deep water), proving to himself that courage can outlast past trauma.

TL;DR: Douglas confirmed he had conquered the old terror by swimming alone in Lake Wentworth and then across Warm Lake, facing the brief return of fear in deep water and overcoming it each time.

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