I was recently asked about Grandpop Kwick's diving, so went looking for a story I had heard once.
Sure enough, Mother had documented it.
Simon Lake was an inventor of the submarine, both for military and commercial uses.
Here is a link to information about his salvage machines.
http://www.simonlake.com/html/salvage_subs.html
It is not difficult to find more about him online.
Simon Lake visited Grandpop Kwick in 1934.
And then wrote to him later.
In 2000, Grace wrote:
" I remember the visit that Simon Lake refers to in this letter. He came to the house one evening and he and Pop talked a long time while a taxi waited in the driveway. Impressive!
..
Simon Lake was interested in Pop's diving to help raise the de Braak which had recently been discovered sunk someplace along the Atlantic Coast. Apparently that fell through, but the de Braak has been in the news off and on ever since, and I think it was finally recovered in the 90s. Someplace I have a newspaper clipping about it.
At the time of his visit I was under the impression that he was the inventor of the submarine, but I don't think that is right. I'll have to look that up."
The HMS de Braak was recovered in 1984, apparently somewhat irresponsibly
http://en.wikipedia.org/wiki/HMS_Braak_%281795%29
http://en.wikipedia.org/wiki/User:Maralia/HMS_De_Braak
It is interesting to note that Nils was 59 years old in 1934.
While the 1910 Census listed his occupation as "submarine diver", in 1920 he is called a carpenter, then in 1930 he is again listed as a diver.
I think there are more records to find.
More diving-related pictures are in this post from January 6, 2012
http://stuffstories.blogspot.com/2012/01/january-6-grandpop-kwicks-birthday.html