The second half of "History in the Making" contributes to the development of the theme that teamwork can make the impossible happen: by explaining how it took many people to coordinate the first successful flight.
In that passage, we learn how John Lee watched excitedly as the first aircraft was set in motion.
The Wright brothers and the other engineers on ground cooperated in setting the tracks that led to the flight of the first aircraft. Their cooperation made the seemingly impossible, possible.
Through their efforts and cooperation, we now have aircraft that can transport people across the world.