The book "On the Bottom": The Raising of the U.S. Navy Submarine S-51" by Edward Ellsberg is a non-fiction account of the efforts to recover the sunken submarine S-51 in 1925. Throughout the book, there are several instances of rising tension as the recovery operation faces numerous challenges.
One example of rising tension in the book occurs when the divers are attempting to attach cables to the submarine in order to lift it to the surface. As they work in the murky and treacherous waters, they encounter unexpected obstacles such as strong currents and tangled debris. In Chapter 16, Ellsberg writes:
"Suddenly the divers found themselves caught in a vortex, and they were being dragged down, down into the dark abyss. The cables tangled around their feet, and they struggled to break free as their air hoses grew taut. Panic set in, and they fought for their lives, thrashing wildly in the churning water."
This example shows how the recovery operation was filled with unexpected challenges and dangerous situations that increased the tension and suspense of the story. The divers' struggle to free themselves and avoid drowning creates a sense of urgency and danger that keeps the reader engaged in the story.