Three travellers, an American, a Russian and an African, were all on a world tour in a hot air balloon. The Russian man puts his hand over the side and feels into the clouds.
"Aaah!" he said, "We're right over my homeland." "How can you tell?" asked the American. "I can feel the cold air" he replied.
A few days later the African man put his hand over the side into the clouds. "Aaah, we're right over my homeland" he said. "How do you know that?" asked the Russian. "I can feel the heat of the Desert."
Several more days later the American put his hand over the side into the clouds. "Aaah, we're right over New York." The Russian and African were amazed. "How did you know all of that?" They exclaimed. The American pulled his hand in and held it up for them to see. "My watch is missing."