Two-wheeled dump carts were common in America prior to the Petroleum Era. This one was purchased in the late 1980s at an antique store in Gap, Pennsylvania.

The shafts are not original and do not have the typical hardware: a metal staple to which the draft, support, and hold-back straps connect on each side. The axle is made of wood and is fixed to the cart bed. 

At the hub, the axle is strengthened with a metal cuff.  The wheel is held in place with a washer and pin. The shafts attach in front of the axle via an iron hook and loop.  This allows the bed to pivot on the axle, into a nearly vertical position without affecting the shafts much. In fact, if the wheels are blocked, the horse (or ox) can dump the wagon by backing.  

Barbara Corson, VMD, retired veterinary pathologist, amateur historian and agrophile