Handy, for sure! Check out those wheels, very modern for the vintage era this is from.
Pic A, shows the at rest position, notice the white arrow providing a centerline for discussion
Pic B, shows the (single pull) of the lever that raises the cart, the black arrow shows the direction of pull
Pic C, shows how the centerline has moved, and is ready to be 'caught" on the hook for safe transport.
Catch and release at its finest.
All said and done, this lifts perhaps an inch at most for transport.