Same image as previous page but closer. It's easier to see the wheel assemblies. Note the end where a wall and door will be placed have two sets of wheels, far right set of wheels on rail. This helps take on that additional weight at that end of the arch. The opposite end of the arch has no walls or doors and therefore doesn't need a double set of wheels. You can also see the small red wheels at either end of the rail/wheel assemblies. More images of this later.
 
 

Arch in the open position, exposing the telescope.