The account of two WW II submarines who, through a weird twist of fate, had their stories intertwined. The Sculpin, in 1939, had helped located and rescue sailors from the Squalus when it went down in 240 feet of water off New Hampshire. Later in the war, the Sailfish, the rechristened Squalus lined up her torpedoes and attacked an enemy escort carrier which, it happens, was transporting prisoners that had been captured from the Sculpin. Many were drowned.

The Sculpin and Squalus were sister submarines launched in 1938. On one of her final trial runs, the induction valve (the huge air intake for the diesel engines) failed to close during a test crash dive and the Squalus sank. This was to be the first test of the Momsen lung (Momsen himself was to participate in the rescue) and the diving bell the Navy had installed and built following numerous submarine losses in the preceding decade. The survivors were now trapped in the control room and torpedo room. Fortunately the sub was not on its side but held a slight 11% upward angle (at 320 feet long, technically the bow, had it had enough buoyancy, I suppose could have stuck up out of the water. One option considered was to attach high pressure air lines to the sub and fill it with enough air to blow it to the surface. They decided to use the rescue bell instead, the first time it was used to rescue sailors trapped in a sub.) A big problem was that the last transmission before they dived to indicate their transmission was garbled slightly in the last digit so they were actually five miles away from where they had reported diving.

Well, enough spoilers. This is a fascinating account of overlapping coincidental tragedies. Submarine service was risky enough and submariners lost their lives at a rate 6 times that of any other service during WW II.

P.S. Excellent detailed website regarding the salvage of the Squalus at http://www.cisatlantic.com/trimix/other/squalus.htm

Another book about the original sinking and salvage of the Squalus is Peter Maas' [b:The Terrible Hours|42639|The Terrible Hours|Peter Maas|http://www.goodreads.com/assets/nocover/60x80.png|1975428]

also[b:A Tale of Two Subs An Untold Story of World War II, Two Sister Ships, and Extraordinary Heroism|2230212|A Tale of Two Subs An Untold Story of World War II, Two Sister Ships, and Extraordinary Heroism|Jonathan J. McCullough|http://d.gr-assets.com/books/1348835721s/2230212.jpg|2236011] ( )