America's economy grew by more than 400% between 1860 and 1900 Technological advances, expanding population, improved transportation, financial innovation, and new business practices combined to fuel this economic growth "Titans of Industry".
This was after the Wars, and people had started to get their lives back. Population increased drastically. There was a need of more food and supplies.
It's why the 50s were called the baby booming era.
The tropic of Capricorn is the circle marking the latitude 23.5 degrees south where the sun is directly overhead at noon on December 21, the beginning of winter in he northern hemisphere.
I believe it was workers, as for example Ford had given workers large wages, enough for them to start buying some of what they made. Hope this helps!
