An old Wild West
An old Wild West fort is about to be attacked. The wily old General sends for his trusty Indian Scout. "You must use all your years of skill in trying to estimate the sort of army we are up against here."
The trusty Indian Scout laid down and put his ear to the ground... "Large war party," he says, "maybe three hundred braves, four chiefs, two on black stallions, two on white stallions. All have war paint ... many, many guns. Medicine man also with them."
"Good grief!" exclaims the General, "you can tell all of that just by listening to the ground???"
"No, General," replied the Scout, "I can see under the gate."