What is the differance between boogers and spinach?
You can't get your kids to eat spinach.
Roller CoasterIn 1898, the loop-de-loop Roller Coaster having a section of vertical circular spiral track was patented by Edwin Prescott (U.S. No. 609164). He described how “due to centrifugal action, the contents of the car remains securely in place and the car follows the track.” The axles of the car’s wheels had the essential ability to pivot slightly on the car frame in both horizontal and vertical directions to closely follow the horizontal and vertical curves of the track. For safety, he provided additional wheels on the opposite side of the main rail with their own safety track to prevent the car from leaving the main track, even if the car was inverted while travelling with insufficient centrifugal force. An elevator chain moved the car from a passenger-station on the ground, up to a much higher section of track as the starting point.« |
