Abstract: A lifting device for lifting cylindrical tanks of the type used by welders is disclosed. The lifting device comprises an elongated lifting arm having a bracket pivotally secured to a midpoint of the arm. Both ends of a chain are secured to the bracket and the chain is dimensioned so that, with the bracket in abutment against the side of the tank, the chain extends around the tank. An abutment member is secured to a lower first end of the lifting arm so that, as the second upper end of the lifting arm is lifted, the tank is mechanically locked between the chain, bracket and the abutment member. A lifting cart having a hoist assembly for lifting the lifting arm is also disclosed.