Lots of humor
During mountain training an instructor in mountain warfare techniques gave the following warning to his charges: "Be careful not to fall here - it's dangerous. But if you do fall, remember to look to the left - you get a wonderful opportunity for observing some dead spaces where the enemy may be."
It was a painful hour of physical training crowded with jumping, pull-ups, climbing, weight carrying, etc.
At last Private Hargreaves exclaimed: "I think I better become a spaceman."
"Why?"
"It'll be much easier to do all these exercises on the Moon."
His little boy was looking through a news-paper.
"Daddy," he asked, "do you remember you told me mushrooms were a nice thing?"
"Yes, what of it?"
"Well, look at this one," said the little boy, pointing at a photo in the paper. That was a photo showing American H-bomb tests at Bikini.