What is in this image? Describe it as if you were explaining it to someone from the 15th century.

This image shows a "mechanical cart," a remarkable type of wagon that requires no horses to move. It features a separate front part that steers and powers the movement, somewhat akin to leading horses, but made entirely of metal and other materials. The rear part is where goods or people may sit, much like a traditional cart. The entire contraption rolls upon large wheels, not unlike those you might see on a mill or a large clockwork device, but rounder and more solid for traveling on diverse terrains. These mechanical carts are propelled by harnessing the energies and principles that govern machines, quite fascinating to behold!