This device is an experimental underwater radio. I was transmitting a voice signal to my friend, Chuck Barron, the inventor of it. He was a member of my underwater flotilla and the Coast Guard Auxiliary. We were making some tests on the tranmitter receiver, hoping to present it to the Navy. I had left Chuck a few hundred feet away. He was going to home in on my signal. It was taking too long. I was beginning to worry. Something was wrong. I didn't have much air left, and that...