My roommate and I were swimming in a sort of pool with a cement foundation, but yet we seemed to be in a river. The water was quite black and we were hanging onto the side watching others dive in. We suddenly found ourselves in another section of the pool, but this was blocked off from the larger part. As we stood in the water, Dorothy Williams, the student instructor, told us we couldn't swim there because there were holes in the cement wall and very likely someone would slip through. Miss Stover, the teacher, came over and as she stood on top of the cement wall, she told us the same thing that Dorothy did.