these pictures are examples of Cape Carts which are unique to South Africa [I think]. They were developed during the Boer War and are a safe way to hitch a pair to a 2-wheeled cart. The harnessing system is a bit different than the "normal" pair harness. this harnessing system enables a pair to safely pull a cart over the roughest country.
this is model of a cape cart
rear view of the model
made in the USA for export
cape_cart.jpg
the important front attachment of a cape harness
a nice design for a dog cart set up in the "cape" style